fix(protocol): remove auto-detection of frame mode and ensure extra chunks are always used for valid waveform footer

fix(protocol): implement auto-detection of frame mode based on probe response size for accurate chunk handling
fix: add new helper (_recv_5a_batch()) that helps with assembling chunks over TCP
2026-04-28 00:05:51 -04:00 · 2026-04-27 23:29:53 -04:00 · 2026-04-27 18:39:34 -04:00 · 2026-04-26 16:32:32 -04:00 · 2026-04-26 16:03:07 -04:00 · 2026-04-26 01:28:47 -04:00
13 changed files with 3043 additions and 156 deletions
@@ -4,6 +4,110 @@ All notable changes to seismo-relay are documented here.

 ---

+## v0.12.5 — 2026-04-21
+
+### Changed
+
+- **`s3_bridge.py` — raw captures always-on by default** — `--raw-bw` and `--raw-s3` now
+  default to `"auto"` instead of `None`. Every bridge session automatically generates
+  timestamped `raw_bw_<ts>.bin` and `raw_s3_<ts>.bin` files alongside the `.bin`/`.log`
+  session files. Pass `--raw-bw ""` (explicit empty string) to disable if needed.
+
+- **`gui_bridge.py` — raw capture checkboxes pre-checked** — Both "BW→S3 raw" and
+  "S3→BW raw" checkboxes start checked. Path fields are empty by default (bridge auto-names
+  the files). Unchecking a box passes `--raw-bw ""` to explicitly disable capture.
+
+- **`ach_server.py` — TX capture added (`raw_tx_<ts>.bin`)** — Every ACH inbound session
+  now saves both directions: `raw_rx_<ts>.bin` (device → us, S3 side, as before) and
+  `raw_tx_<ts>.bin` (us → device, BW side). Both files are usable in the Analyzer.
+  TX bytes are buffered in memory until startup handshake succeeds (same as RX), preventing
+  scanner probes from creating empty files.
+
+---
+
+## v0.12.4 — 2026-04-21 (protocol analysis / docs only — no code changes)
+
+### Discovered
+
+- **compliance_raw is wire-encoded, not logical bytes** — `read_compliance_config()` returns
+  bytes that include DLE prefix bytes (`0x10`) before any `0x03` values (because S3FrameParser
+  preserves DLE+ETX inner-frame pairs as two literal bytes). The previous CLAUDE.md claim that
+  "S3FrameParser handles this transparently so compliance_raw contains logical bytes" was wrong.
+
+- **anchor-9 behavior per recording mode** (confirmed from 4-20-26 BW write captures):
+  - Single Shot (0x00) / Continuous (0x01): anchor-9 = `0x00`
+  - Histogram (0x03): anchor-9 = `0x10` — the E5 DLE prefix for the `0x03` recording_mode byte
+  - Histogram+Continuous (0x04): anchor-9 = `0x10` — an actual stored config byte for this mode
+  Anchor position shifts by ±1 when recording_mode = `0x03` due to the extra DLE byte; the
+  dynamic anchor search (`buf.find(ANCHOR, 0, 150)`) handles this correctly without code changes.
+
+- **Write frame ETX escaping** — BW escapes `0x03` bytes in write frame data as `0x10 0x03`
+  on the wire. Our `build_bw_write_frame` sends data bytes raw without ETX escaping. Device
+  accepts our raw writes for all tested modes. Hypothesis: device write parser uses the
+  offset/length field for frame boundaries, not ETX scanning, making ETX escaping optional.
+  Histogram mode (recording_mode = 0x03) write via SFM from a non-Histogram starting state
+  not yet tested.
+
+- **BW write payload vs E5 read payload are byte-identical** around the anchor region (confirmed
+  by comparing 3-11-26 BW TX and S3 captures). BW does NOT strip DLE prefix bytes before writing;
+  it round-trips the wire-encoded bytes verbatim with only the modified fields changed.
+
+- **Capture folder content catalogued** — see CLAUDE.md "BW capture reference" table for a
+  summary of all available protocol captures and their contents.
+
+---
+
+## v0.12.3 — 2026-04-20
+
+### Added
+
+- **Auto Call Home config protocol** — Full read/write/decode/encode pipeline for the
+  device's Remote Access → Setup Unit ACH settings, confirmed from 4-20-26 call home
+  settings captures.
+
+  **Protocol (new):**
+  - `SUB 0x2C` — Call Home Config READ (response `0xD3`); two-step read; data offset
+    `0x7C` = 124; raw payload 125 bytes (1-byte longer than DATA_LENGTH due to DLE-escaped
+    `\x10\x03` at raw[117:119] representing num_retries = 3)
+  - `SUB 0x7E` — Call Home Config WRITE (response `0x81`); 127-byte payload (125-byte read
+    payload + `\x00\x00`); offset = `data[1]+2 = 0x7E`; write format (DLE-aware checksum)
+  - `SUB 0x7F` — Call Home WRITE CONFIRM (response `0x80`); no data
+
+  **Field map (confirmed from 10-frame BW TX diff):**
+  - `raw[5]` — auto_call_home_enabled (bool)
+  - `raw[6:46]` — dial_string (40-byte null-padded ASCII)
+  - `raw[87]` — after_event_recorded (bool)
+  - `raw[91]` — at_specified_times (bool)
+  - `raw[93]` — time1_enabled / `raw[101]` — time1_hour / `raw[102]` — time1_min
+  - `raw[95]` — time2_enabled / `raw[105]` — time2_hour / `raw[106]` — time2_min
+  - `raw[117:119]` — `\x10\x03` (DLE-escaped 0x03 = num_retries value 3)
+  - `raw[120]` — time_between_retries_sec / `raw[122]` — wait_for_connection_sec / `raw[124]` — warm_up_time_sec
+
+  **Library (`minimateplus/`):**
+  - `models.py` — `CallHomeConfig` dataclass (14 fields; `raw` bytes preserved for
+    round-trip writes)
+  - `protocol.py` — `SUB_CALL_HOME = 0x2C`, `SUB_CALL_HOME_WRITE = 0x7E`,
+    `SUB_CALL_HOME_CONFIRM = 0x7F`; `read_call_home_config()`, `write_call_home_config()`
+  - `client.py` — `get_call_home_config()`, `set_call_home_config()`,
+    `_decode_call_home_config()` (handles DLE prefix at raw[117]),
+    `_encode_call_home_config()` (patches in-place; raises `ValueError` if hour/min = 3)
+
+  **REST API (`sfm/server.py`):**
+  - `GET /device/call_home` — reads and decodes call home config from device
+  - `POST /device/call_home` — reads, patches specified fields, writes back to device
+  - `CallHomeConfigBody` Pydantic model with 9 optional writable fields
+
+  **Web UI (`sfm/sfm_webapp.html`):**
+  - New "Call Home" tab with enable flag, dial string (read-only), after-event trigger,
+    at-specified-times flag, two time slots (enable + HH:MM each), and read-only retry
+    settings (num_retries, time_between_retries_sec, wait_for_connection_sec,
+    warm_up_time_sec)
+  - "Read from Device", "Write to Device", "Clear Form" action buttons
+  - Client-side guard: rejects hour or minute value equal to 3 with a clear message
+    explaining the DLE-encoding limitation
+
+---
+
 ## v0.12.2 — 2026-04-20

 ### Added / Fixed
@@ -2,7 +2,7 @@

 Ground-up Python replacement for **Blastware**, Instantel's Windows-only software for
 managing MiniMate Plus seismographs. Connects over direct RS-232 or cellular modem
-(Sierra Wireless RV50 / RV55). Current version: **v0.12.2**.
+(Sierra Wireless RV50 / RV55). Current version: **v0.12.3**.

 When new information about the protocol is discovered, please update the instantel_protocol_reference.md with the findings in addition to this document

@@ -27,9 +27,9 @@ CHANGELOG.md          ← version history

 ---

-## Current implementation state (v0.10.0)
+## Current implementation state (v0.12.3)

-Full read pipeline + write pipeline + erase pipeline + monitor log working end-to-end over TCP/cellular:
+Full read pipeline + write pipeline + erase pipeline + monitor log + call home config working end-to-end over TCP/cellular:

 | Step | SUB | Status |
 |---|---|---|
@@ -45,7 +45,8 @@ Full read pipeline + write pipeline + erase pipeline + monitor log working end-t
 | Event advance / next key | 1F | ✅ |
 | **Write commands (push config to device)** | **68–83** | ✅ new v0.8.0 |
 | **Erase all events** | **0xA3 → 0x1C → 0x06 → 0xA2** | ✅ new v0.9.0 |
-| **Monitor log entries (partial 0x2C records)** | **0A browse** | ✅ **new v0.10.0** |
+| **Monitor log entries (partial 0x2C records)** | **0A browse** | ✅ new v0.10.0 |
+| **Auto Call Home config (read + write)** | **2C → 7E → 7F** | ✅ **new v0.12.3** |

 `get_events()` sequence per event: `1E → 0A → 0C → 5A → 1F`

@@ -117,21 +118,29 @@ S3→BW (response):
 Both differences confirmed by reproducing Blastware's exact wire bytes from the 1-2-26
 BW TX capture. All 10 frames verified.

-### SUB 5A — chunk counter is monotonic (CORRECTED 2026-04-06)
+### SUB 5A — chunk counter formula (FINAL CORRECTION 2026-04-26)

-**Chunk counters are `chunk_num * 0x0400` for ALL chunks including chunk 1.**
+**Chunk counter = `max(key4[2:4], 0x0400) + (chunk_num - 1) * 0x0400` for ALL chunks.**

-The 4-2-26 BW TX capture showed `counter=0x1004` for chunk 1 of event key `01110000`, which
-led to `_CHUNK1_COUNTER = 0x1004` being hardcoded as a special case. This was a Blastware
-artifact, not a protocol requirement. Empirical test 2026-04-06: with `counter=0x1004` for
-chunk 1 the device times out (120 s); with `counter=0x0400` (= `1 * 0x0400`) it responds
-immediately and streams all frames correctly.
+where `key4[2:4] = (key4[2] << 8) | key4[3]` is the event's circular-buffer base offset.

-The 4-3-26 capture confirms the pattern for a second event (key `0111245a`):
-chunk 1 = `0x245A`, chunk 2 = `0x285A`, chunk 3 = `0x2C5A` (each +0x0400). Blastware's
-true formula is `key4[2:4] + n * 0x0400` — but since `key4[2:4]` of the first event is
-`0x0000`, `n * 0x0400` produces the right result. The device does not strictly validate the
-counter and streams data for any valid 5A request; using `chunk_num * 0x0400` is correct.
+The `max(..., 0x0400)` guard is critical for events at the start of the circular buffer
+(key4[2:4] == 0x0000, e.g. key `01110000`). Without it, chunk 1 gets counter=0x0000, which
+is the same address as the probe frame — the device re-returns the STRT record data instead
+of waveform payload. With the guard, chunk 1 gets counter=0x0400, which is confirmed correct
+from the empirical live-device test 2026-04-06 (`counter=0x0400 → responds immediately and
+streams all frames correctly`).
+
+The 4-3-26 capture confirms the pattern for a second event (key `0111245a`, key4[2:4]=0x245a):
+chunk 1 = `0x245A`, chunk 2 = `0x285A`, chunk 3 = `0x2C5A` (each +0x0400).
+`max(0x245a, 0x0400) = 0x245a` → formula works correctly for non-zero base offset too.
+
+**History:**
+- Original: `_CHUNK1_COUNTER = 0x1004` hardcoded (Blastware capture artifact — WRONG).
+- 2026-04-06: Corrected to `chunk_num * 0x0400` (worked for key 01110000 only).
+- 2026-04-24: Corrected to `key4[2:4] + (chunk_num-1) * 0x0400` (fixed non-zero offsets,
+  but accidentally broke key 01110000 — counter=0x0000 sends probe address again).
+- 2026-04-26: Final formula: `max(key4[2:4], 0x0400) + (chunk_num-1) * 0x0400`.

 ### SUB 5A — params are 11 bytes for chunk frames, 10 for termination

@@ -338,6 +347,36 @@ Do NOT use fixed absolute offsets for sample_rate or record_time.
  Quiet Mode enabled. Parser handles this — do not strip it manually before feeding to
  `S3FrameParser`.

+**SUB 5A (bulk waveform) TCP frame splitting — confirmed 2026-04-27:**
+
+Over TCP via cellular modem, each 5A chunk request that produces a single ~1100-byte
+A5 response over direct RS-232 may arrive as **two separate, complete S3 frames** of
+~550 bytes each ("2-frame mode").  The modem's Data Forwarding Timeout (~100-150 ms)
+can split the RS-232 response into two TCP segments, each parsed as a complete S3 frame.
+Under different modem/timing conditions the full ~1100-byte response arrives as **one
+S3 frame** ("1-frame mode").
+
+**Both modes require `extra_chunks_after_metadata=1`** (the extra chunk at metadata_counter
+ 0x0400).  The device's waveform footer data lives at circular-buffer address 0x1C00 for
+this event; the terminator frame must be sent at 0x1C00 (not 0x1800) to receive it.
+
+Example for a 2-second Continuous event (BE11529, key=01110000) via TCP:
+- **2-frame mode:** 1 probe frame (554 B) + 5 chunks × 2 frames (556-573 B) + 1 extra chunk × 2 frames + 1 terminator (208 B) = **14 A5 frames** → 6864-byte file
+- **1-frame mode:** 1 probe frame (~1097 B) + 5 chunks × 1 frame (~1079-1113 B) + 1 extra chunk × 1 frame (smaller, tail of event) + 1 terminator → **8 A5 frames** → 6864-byte file
+- All frames contribute body data; using all of them gives the correct file.
+
+**Fix (confirmed 2026-04-27):**  `_recv_5a_batch()` in `protocol.py` collects ALL
+A5 frames per chunk request before the next request is sent, using a 0.5 s batch
+timeout after the first frame to catch the ~150 ms delayed second frame.  `write_blastware_file()`
+includes ALL body frames without skipping — the extra chunk's frames are part of the
+body data, NOT padding to be discarded.
+
+**WRONG earlier hypothesis (do not re-introduce):** An attempt was made to auto-detect
+1-frame vs 2-frame mode from the probe frame size and skip the extra chunk when
+`probe_data_len >= 700`.  This was wrong — the extra chunk is always needed to advance
+the device's internal state to the footer address.  The `_probe_is_large` branch was
+removed 2026-04-27.
+
 ### Required ACEmanager settings (Sierra Wireless RV50/RV55)

 | Setting | Value | Why |
@@ -385,7 +424,9 @@ bytes `\x01\x2c` = 300 (5-minute default histogram interval); changes when inter

 | Offset | Field | Format | Notes |
 |---|---|---|---|
-| anchor − 7 (write) / anchor − 8 (read) | recording_mode | uint8 | E5 read has extra `0x10` at anchor−7 |
+| anchor − 9 | mode_prefix | uint8 | `0x00` for Single Shot / Continuous; `0x10` for Histogram (DLE prefix in E5 encoding) and Histogram+Continuous (actual config byte). See "compliance_raw DLE encoding" note below. |
+| anchor − 8 | recording_mode | uint8 | **Same offset for both read and write** — confirmed 2026-04-21. `_encode_compliance_config` writes `buf[anc-8]`. NOTE: for Histogram (0x03), E5 encodes the value as `0x10 0x03` so compliance_raw[anc-9]=0x10, compliance_raw[anc-8]=0x03. |
+| anchor − 7 | constant | `0x10` | Always `0x10` in both E5 read and BW write payloads (not a DLE marker — it is part of the sample_rate field area). Do NOT overwrite. |
 | anchor − 6 | sample_rate | uint16 BE | same in read & write |
 | anchor − 4 | histogram_interval_sec | uint16 BE | seconds; same in read & write ✅ 2026-04-20 |
 | anchor − 2 | `0x00 0x00` | padding | |
@@ -394,15 +435,42 @@ bytes `\x01\x2c` = 300 (5-minute default histogram interval); changes when inter

 **recording_mode enum** (confirmed 2026-04-20 from 4-20-26 captures):

-| Value | Mode |
-|---|---|
-| `0x00` | Single Shot |
-| `0x01` | Continuous |
-| `0x02` | ❓ not observed |
-| `0x03` | Histogram |
-| `0x04` | Histogram + Continuous |
+| Value | Mode | anchor-9 in compliance_raw |
+|---|---|---|
+| `0x00` | Single Shot | `0x00` |
+| `0x01` | Continuous | `0x00` |
+| `0x02` | ❓ not observed | ❓ |
+| `0x03` | Histogram | `0x10` (DLE prefix from E5 wire encoding of 0x03) |
+| `0x04` | Histogram + Continuous | `0x10` (actual config byte for this mode) |

-**DLE escaping in write frames — CONFIRMED 2026-04-20:** Write frame data payloads DO escape `0x03` (ETX) bytes with a `0x10` DLE prefix. For histogram_interval = 900 (0x0384), the wire carries `10 03 84` — the `0x03` high byte is preceded by a DLE escape. After DLE destuffing (`10 XX → XX`), the logical field value is correctly `03 84` = 900. The CLAUDE.md claim that write frame data is "written RAW" was incorrect; at minimum ETX (0x03) bytes are escaped. S3FrameParser handles this transparently so the decoded `compliance_raw` always contains logical (destuffed) bytes.
+**compliance_raw DLE encoding — IMPORTANT (confirmed 2026-04-21 from 4-20-26 captures):**
+`compliance_raw` (returned by `read_compliance_config()`) is NOT purely logical bytes — it is
+the wire-encoded representation where `0x03` bytes in the config are preceded by a `0x10` DLE
+prefix (because S3FrameParser preserves DLE+ETX inner-frame pairs as two literal bytes).
+
+Consequences:
+- When recording_mode = `0x03` (Histogram), `compliance_raw[anc-9] = 0x10` (DLE prefix) and
+  `compliance_raw[anc-8] = 0x03` (the value). The anchor position is +1 compared to modes
+  without `0x03` bytes before the anchor.
+- For Histogram+Continuous (`0x04`), `compliance_raw[anc-9] = 0x10` for a different reason:
+  it is an actual stored config byte, not a DLE prefix.
+- The anchor search (`buf.find(b'\xbe\x80\x00\x00\x00\x00', 0, 150)`) correctly locates
+  the anchor regardless of these mode-dependent shifts.
+- When SFM writes recording_mode and round-trips the rest verbatim, the byte at `anc-9` is
+  preserved from the previous read. This means transitioning Histogram→other modes via SFM
+  leaves a `0x10` at `anc-9`. The device stores it as a literal byte; it does not affect
+  recording mode operation (which is at `anc-8`), but differs from what BW writes. This is a
+  known minor discrepancy that does not impact device behavior.
+- **Histogram recording mode (0x03) write via SFM**: untested. When starting from a mode with
+  `anc-9 = 0x00`, SFM writes bare `0x03` at anc-8. BW would write `0x10 0x03`. Device likely
+  accepts both (write frames probably use offset/length for framing, not ETX scanning).
+
+**DLE escaping in write frames — confirmed 2026-04-20:** Blastware escapes `0x03` bytes in
+write frame data as `0x10 0x03` on the wire (defensive ETX escaping). Our `build_bw_write_frame`
+does NOT do this escaping — it sends data bytes raw. Device acceptance of bare `0x03` bytes
+in write frame data is confirmed for the tested modes (Single Shot, Continuous, Histogram+Continuous
+where `0x10 0x03` already appears from round-tripping). Histogram mode (bare `0x03` write from
+non-Histogram starting state) has not been directly tested.

 ### SUB 0C — Waveform Record (210 bytes = data[11:11+0xD2])

@@ -971,12 +1039,148 @@ call-home.

 ---

+## Auto Call Home config (SUBs 0x2C / 0x7E / 0x7F) — confirmed 2026-04-20
+
+Full read/write pipeline confirmed from `bridges/captures/4-20-26/call home settings/`
+(10 BW TX write frames diffed against the S3 read response).
+
+Accessible in Blastware: **Remote Access → Setup Unit**.
+
+### Protocol
+
+**SUB 0x2C — Call Home Config READ (response 0xD3)**
+
+Standard two-step read: probe offset `0x0000`, data offset `0x007C` (124).
+Returns 125 raw bytes (one more than DATA_LENGTH) because the device encodes
+num_retries value `3` as `\x10\x03` on the wire — S3FrameParser preserves both
+bytes literally, shifting all subsequent field positions by +1.
+
+**SUB 0x7E — Call Home Config WRITE (response 0x81)**
+
+Write format (only BW_CMD `0x10` doubled on wire; DLE-aware checksum).
+Payload = 125-byte read payload + `\x00\x00` = 127 bytes.
+Offset = `data[1] + 2 = 0x7C + 2 = 0x7E`.
+
+**SUB 0x7F — Call Home WRITE CONFIRM (response 0x80)**
+
+Confirm frame, no data payload. Required after SUB 0x7E.
+
+### Field map (raw 125-byte array from `data_rsp.data[11:]`)
+
+| Raw Offset | Field | Notes |
+|---|---|---|
+| `[5]` | `auto_call_home_enabled` | `0x00`=off, `0x01`=on |
+| `[6:46]` | `dial_string` | 40-byte null-padded ASCII |
+| `[87]` | `after_event_recorded` | bool |
+| `[91]` | `at_specified_times` | bool |
+| `[93]` | `time1_enabled` | bool |
+| `[101]` | `time1_hour` | 0–23 |
+| `[102]` | `time1_min` | 0–59 |
+| `[95]` | `time2_enabled` | bool |
+| `[105]` | `time2_hour` | 0–23 |
+| `[106]` | `time2_min` | 0–59 |
+| `[117]` | DLE prefix `0x10` | Part of `\x10\x03` (DLE-escaped ETX encoding value 3) |
+| `[118]` | `num_retries` | Value = 3; detect via `raw[117] == 0x10` |
+| `[120]` | `time_between_retries_sec` | Shifted +1 from logical 119 |
+| `[122]` | `wait_for_connection_sec` | Shifted +1 from logical 121 |
+| `[124]` | `warm_up_time_sec` | Shifted +1 from logical 123 |
+
+**DLE-escaped 0x03 at raw[117:119]:** The byte value `0x03` is indistinguishable from the
+frame ETX terminator, so the device encodes it as `\x10\x03` (DLE + ETX inner-terminator).
+S3FrameParser in `STATE_AFTER_DLE` on ETX appends both bytes as literal payload. The write
+frame sends them verbatim — device accepts `\x10\x03` and interprets it as value 3.
+
+**Unconfirmed fields:** time slots 3 and 4 (offsets unknown), `modem_power_relay_enabled`.
+
+### `CallHomeConfig` model — models.py
+
+```python
+@dataclass
+class CallHomeConfig:
+    raw: Optional[bytes] = None                        # 125-byte raw read payload
+    auto_call_home_enabled: Optional[bool] = None      # raw[5]
+    dial_string: Optional[str] = None                  # raw[6:46]
+    after_event_recorded: Optional[bool] = None        # raw[87]
+    at_specified_times: Optional[bool] = None          # raw[91]
+    time1_enabled: Optional[bool] = None               # raw[93]
+    time1_hour: Optional[int] = None                   # raw[101]
+    time1_min: Optional[int] = None                    # raw[102]
+    time2_enabled: Optional[bool] = None               # raw[95]
+    time2_hour: Optional[int] = None                   # raw[105]
+    time2_min: Optional[int] = None                    # raw[106]
+    num_retries: Optional[int] = None                  # raw[118] (DLE-prefixed)
+    time_between_retries_sec: Optional[int] = None     # raw[120] (shifted +1)
+    wait_for_connection_sec: Optional[int] = None      # raw[122] (shifted +1)
+    warm_up_time_sec: Optional[int] = None             # raw[124] (shifted +1)
+```
+
+### SFM REST API — sfm/server.py
+
+```
+GET  /device/call_home?host=1.2.3.4&tcp_port=9034   ← read call home config
+POST /device/call_home?host=1.2.3.4&tcp_port=9034   ← write call home config
+```
+
+POST body fields (all optional): `auto_call_home_enabled`, `after_event_recorded`,
+`at_specified_times`, `time1_enabled`, `time1_hour`, `time1_min`, `time2_enabled`,
+`time2_hour`, `time2_min`.
+
+**Note:** `dial_string` is read-only in the current implementation (omitted from POST
+body) because writing a dial string may require DLE escaping for embedded control characters.
+
+---
+
 ## What's next

 - **Database** — SQLite store for events + monitor log entries; dedup by key; queryable
 - **Histograms** — decode histogram-mode A5 data (noise floor tracking)
+- **Blastware-compatible file output** — `write_blastware_file()` and `write_mlg()` implemented. `blastware_filename()` generates correct Blastware filenames (AB0 for direct, AB0W/AB0H for ACH). **Confirmed working for Continuous mode events (2026-04-23):** SFM-generated file opens in Blastware, shows correct PPV/waveform/timestamp. File is ~200 bytes shorter than BW (missing last ADC tail slice) — all measurements correct. Histogram+Continuous mode deferred (5A stream for those events embeds histogram interval records that create spurious STRT markers in the body). Extension mapping: **CONFIRMED FALSE 2026-04-21** — extensions encode timestamp (AB0T for ACH, AB0 for direct), NOT recording mode. Filename format: `<prefix_letter><serial3><4-char-base36-stem><ext>`
+
+  **Serial encoding (CONFIRMED 2026-04-22):** `prefix_letter = chr(ord('B') + floor(serial_numeric / 1000))`, `serial3 = f"{serial_numeric % 1000:03d}"`. Examples: BE6907→H907, BE11529→M529, BE14036→P036, BE17353→S353, BE18003→T003. The prefix letter encodes the production generation (batch of 1000 units).
+
+  **Stem encoding (FULLY CONFIRMED 2026-04-22):** stem = 4-char base-36 of `floor(total_seconds / 1296)` where `total_seconds = (event_local_time − 1985-01-01T00:00:00_local)` in seconds. Epoch = `1985-01-01 00:00:00` device local time — confirmed against 3,248 files from 10-year production archive with zero errors. Decode: `event_time = datetime(1985,1,1) + timedelta(seconds=stem_int*1296 + ab_int)`. Example: P036L318.C80H → BE14036, 2025-05-26 15:00:08, Full Histogram.
+- **Blastware filename extension — NEW FIRMWARE FULLY DECODED (confirmed 2026-04-21, further confirmed 2026-04-22 from 10-year production archive frequency analysis):**
+
+  Extension format = `AB0T` (4 chars):
+  - `AB` = 2-char base-36 encoding of `total_seconds % 1296` (seconds within the 21.6-min window, 0–1295); `A = value // 36`, `B = value % 36`
+  - `0` = always literal digit zero (third character, invariant)
+  - `T` = event type: `W` = Full Waveform, `H` = Full Histogram
+
+  Combined with the 4-char stem, the full filename encodes a complete second-resolution timestamp. Verified against three S353L4H0.{3M0W,8S0H,9X0W} events (all match to the second) plus large-scale frequency analysis of a 10-year archive.
+
+  **3-day cycle property (confirmed 2026-04-22):** A unit recording at a fixed daily time cycles through exactly **3 extensions** with a 3-day period. Each calendar day shifts `total_seconds % 1296` by 864 (since `86400 % 1296 = 864`). The cycle repeats every 3 days because `gcd(1296, 864) = 432` and `1296 / 432 = 3`. The three extension values are spaced 432 seconds apart. Confirmed from 10-year archive: the top 3 extensions overall were `CE0H` (95 files), `0E0H` (93), `OE0H` (91) — all three are the 3-day cycle of a 06:00:14 daily call-in time (seconds-in-window = 14, 446, 878; all three have `E` as second character because `14 = E` in base-36 and adding 864 never changes `value % 36` since `864 = 24 × 36`).
+
+  **B character invariance:** For a unit recording at a fixed time of day, the second character `B` of the extension (`value % 36`) **never changes** — only the first character `A` cycles through 3 values. This means same-time-of-day files from different dates all share the same `B` character.
+
+  **Old firmware (S338, 3-char extensions ending in `0`):** encoding unknown. Extension is NOT recording mode. `blastware_filename()` returns `.N00` as a placeholder for old-firmware units.
+
+  **Micromate Series 4** uses a different extension format entirely (observed: `IDFH`, `IDFW`). The `AB0T` formula applies only to MiniMate Plus / V10.72 firmware.
 - Compliance config encoder — build raw write payloads from a `ComplianceConfig` object
+- **Test Histogram recording mode (0x03) write via SFM** — confirmed working for Single Shot / Continuous / Histogram+Continuous; Histogram (0x03) needs a live test from a non-Histogram starting state (bare 0x03 in write vs BW's DLE-escaped `10 03`)
+- **Compliance write anchor-9 cleanup** — when changing recording_mode via SFM, the byte at anchor-9 is not explicitly managed. A spurious `0x10` may persist after Histogram→other mode transitions. Does not affect device operation but differs from BW's byte-perfect output.
 - Locate "Sensor Check" byte in compliance config (need capture with Disabled vs Before-monitoring)
+- Call Home — map time slots 3/4 offsets; add dial_string write support; confirm `modem_power_relay_enabled`
 - Modem manager — push RV50/RV55 configs via Sierra Wireless API
 - RV55 DCD/DTR issue — newer RV55 firmware doesn't assert DCD by default; units don't
-  resume monitoring after call-home disconnect (`--restart-monitoring` flag deferred)
+  resume monitoring after call-home disconnect (`--restart-monitoring` flag deferred)
+
+## BW capture reference
+
+`bridges/captures/` contains the following BW TX + S3 response captures for protocol analysis:
+
+| Folder / File | Contents |
+|---|---|
+| `3-11-26/raw_bw_20260311_170151.bin` | Full compliance write + event download (SUBs 68→83 confirmed, frames 102–112) |
+| `4-20-26/raw_bw_*_recording_mode_*.bin` | Recording mode changes: Continuous→Single Shot, →Histogram, →Histogram+Continuous |
+| `4-20-26/histogram interval/` | Histogram interval changes: 1min, 5min, 15min, 15sec |
+| `4-20-26/geo sensitivity/` | Geo sensitivity changes: 1.25 in/s (Sensitive), 10 in/s (Normal) |
+| `4-20-26/call home settings/` | Call home config read/write captures |
+| `4-8-26/` | Monitor status read, start/stop monitoring, SESSION_RESET signal, sensor check |
+| `4-3-26-multi_event/` | Browse-mode S3 capture with 2+ events (1E/0A/1F iteration confirmed) |
+| `4-2-26/` | Download-mode BW TX capture (5A bulk stream, POLL×3 requirement confirmed) |
+| `3-31-26/` | Single-event download (148 BW / 147 S3 frames) |
+| `mitm/ach_mitm_20260411_001912/` | Full ACH call-home MITM (erase protocol, 0xA3/0x06/0xA2 confirmed) |
+
+To parse BW TX captures: use `bridges/captures/` scripts or adapt the `find_write_frames()` pattern
+in `/tmp/analyze_write_payload.py` — it correctly handles `0x10 0x03` DLE-escaped ETX bytes
+inside write frame data (the naive parser terminates early at the escaped `0x03`).
@@ -35,6 +35,7 @@ Output per session
    device_info.json   — serial number, firmware version, calibration date, etc.
    events.json        — all events: timestamp, PPV per channel, peaks, metadata
    raw_rx_<ts>.bin    — raw bytes from the device (S3 side) for Analyzer
+    raw_tx_<ts>.bin    — raw bytes we sent to the device (BW side) for Analyzer
    session_<ts>.log   — detailed protocol log

 What to look for
@@ -172,16 +173,24 @@ class AchSession:
        transport = SocketTransport(self.sock, peer=self.peer)

        # Collect raw bytes in memory until startup succeeds, then flush to disk.
-        raw_buf: list[bytes] = []
+        raw_rx_buf: list[bytes] = []   # device → us  (S3 side)
+        raw_tx_buf: list[bytes] = []   # us → device  (BW side)
        _orig_read  = transport.read
+        _orig_write = transport.write

        def tapped_read(n: int) -> bytes:
            data = _orig_read(n)
            if data:
-                raw_buf.append(data)
+                raw_rx_buf.append(data)
            return data

+        def tapped_write(data: bytes) -> None:
+            _orig_write(data)
+            if data:
+                raw_tx_buf.append(data)
+
        transport.read  = tapped_read   # type: ignore[method-assign]
+        transport.write = tapped_write  # type: ignore[method-assign]

        serial: Optional[str] = None

@@ -202,22 +211,34 @@ class AchSession:
        session_dir = self.output_dir / f"ach_inbound_{ts}"
        session_dir.mkdir(parents=True, exist_ok=True)
        log_path   = session_dir / f"session_{ts}.log"
-        raw_path = session_dir / f"raw_rx_{ts}.bin"
+        raw_rx_path = session_dir / f"raw_rx_{ts}.bin"   # device → us  (S3 side)
+        raw_tx_path = session_dir / f"raw_tx_{ts}.bin"   # us → device  (BW side)

-        # Flush buffered raw bytes to file and switch to direct file writes.
-        raw_fh = open(raw_path, "wb")
-        for chunk in raw_buf:
-            raw_fh.write(chunk)
-        raw_buf.clear()
+        # Flush buffered bytes to files and switch to direct file writes.
+        raw_rx_fh = open(raw_rx_path, "wb")
+        raw_tx_fh = open(raw_tx_path, "wb")
+        for chunk in raw_rx_buf:
+            raw_rx_fh.write(chunk)
+        for chunk in raw_tx_buf:
+            raw_tx_fh.write(chunk)
+        raw_rx_buf.clear()
+        raw_tx_buf.clear()

        def tapped_read_file(n: int) -> bytes:
            data = _orig_read(n)
            if data:
-                raw_fh.write(data)
-                raw_fh.flush()
+                raw_rx_fh.write(data)
+                raw_rx_fh.flush()
            return data

+        def tapped_write_file(data: bytes) -> None:
+            _orig_write(data)
+            if data:
+                raw_tx_fh.write(data)
+                raw_tx_fh.flush()
+
        transport.read  = tapped_read_file   # type: ignore[method-assign]
+        transport.write = tapped_write_file  # type: ignore[method-assign]

        # Wire up file handler now that the session dir exists.
        fh = logging.FileHandler(log_path, encoding="utf-8")
@@ -530,7 +551,8 @@ class AchSession:
                    log.warning("  [WARN] Failed to restart monitoring: %s", exc)

        finally:
-            raw_fh.close()
+            raw_rx_fh.close()
+            raw_tx_fh.close()
            client.close()  # closes transport / socket cleanly
            root_logger.removeHandler(fh)
            fh.close()
@@ -58,16 +58,24 @@ class BridgeGUI(tk.Tk):
        tk.Entry(self, textvariable=self.logdir_var, width=24).grid(row=1, column=3, sticky="we", **pad)
        tk.Button(self, text="Browse", command=self._choose_dir).grid(row=1, column=4, sticky="w", **pad)

-        # Row 2: Raw taps
-        self.raw_bw_var = tk.StringVar(value="")
-        self.raw_s3_var = tk.StringVar(value="")
-        tk.Checkbutton(self, text="Save BW->S3 raw", command=self._toggle_raw_bw, onvalue="1", offvalue="").grid(row=2, column=0, sticky="w", **pad)
-        tk.Entry(self, textvariable=self.raw_bw_var, width=28).grid(row=2, column=1, columnspan=3, sticky="we", **pad)
-        tk.Button(self, text="...", command=lambda: self._choose_file(self.raw_bw_var, "bw")).grid(row=2, column=4, **pad)
+        # Row 2: Raw taps — ON by default; "auto" = timestamped name; blank checkbox = disabled
+        self.raw_bw_enabled = tk.IntVar(value=1)
+        self.raw_s3_enabled = tk.IntVar(value=1)
+        # Path fields: empty means "auto" (bridge picks a timestamped name)
+        self.raw_bw_path_var = tk.StringVar(value="")
+        self.raw_s3_path_var = tk.StringVar(value="")

-        tk.Checkbutton(self, text="Save S3->BW raw", command=self._toggle_raw_s3, onvalue="1", offvalue="").grid(row=3, column=0, sticky="w", **pad)
-        tk.Entry(self, textvariable=self.raw_s3_var, width=28).grid(row=3, column=1, columnspan=3, sticky="we", **pad)
-        tk.Button(self, text="...", command=lambda: self._choose_file(self.raw_s3_var, "s3")).grid(row=3, column=4, **pad)
+        tk.Checkbutton(self, text="BW→S3 raw (auto)", variable=self.raw_bw_enabled,
+                       command=self._toggle_raw_bw).grid(row=2, column=0, sticky="w", **pad)
+        tk.Entry(self, textvariable=self.raw_bw_path_var, width=28,
+                 fg="grey").grid(row=2, column=1, columnspan=3, sticky="we", **pad)
+        tk.Button(self, text="...", command=lambda: self._choose_file(self.raw_bw_path_var, "bw")).grid(row=2, column=4, **pad)
+
+        tk.Checkbutton(self, text="S3→BW raw (auto)", variable=self.raw_s3_enabled,
+                       command=self._toggle_raw_s3).grid(row=3, column=0, sticky="w", **pad)
+        tk.Entry(self, textvariable=self.raw_s3_path_var, width=28,
+                 fg="grey").grid(row=3, column=1, columnspan=3, sticky="we", **pad)
+        tk.Button(self, text="...", command=lambda: self._choose_file(self.raw_s3_path_var, "s3")).grid(row=3, column=4, **pad)

        # Row 4: Status + buttons
        self.status_var = tk.StringVar(value="Idle")
@@ -102,13 +110,11 @@ class BridgeGUI(tk.Tk):
            var.set(filename)

    def _toggle_raw_bw(self) -> None:
-        if not self.raw_bw_var.get():
-            # default name
-            self.raw_bw_var.set(os.path.join(self.logdir_var.get(), "raw_bw.bin"))
+        # Checkbox toggled — no path action needed; enabled state drives the flag.
+        pass

    def _toggle_raw_s3(self) -> None:
-        if not self.raw_s3_var.get():
-            self.raw_s3_var.set(os.path.join(self.logdir_var.get(), "raw_s3.bin"))
+        pass

    def start_bridge(self) -> None:
        if self.process and self.process.poll() is None:
@@ -126,23 +132,22 @@ class BridgeGUI(tk.Tk):

        args = [sys.executable, BRIDGE_PATH, "--bw", bw, "--s3", s3, "--baud", baud, "--logdir", logdir]

-        ts = datetime.datetime.now().strftime("%Y%m%d_%H%M%S")
+        # Raw tap flags.
+        # Checkbox on + empty path → pass "auto" (bridge generates timestamped name).
+        # Checkbox on + explicit path → pass that path.
+        # Checkbox off → pass "" to disable (overrides bridge's auto default).
+        raw_bw_explicit = self.raw_bw_path_var.get().strip()
+        raw_s3_explicit = self.raw_s3_path_var.get().strip()

-        raw_bw = self.raw_bw_var.get().strip()
-        raw_s3 = self.raw_s3_var.get().strip()
+        if self.raw_bw_enabled.get():
+            args += ["--raw-bw", raw_bw_explicit if raw_bw_explicit else "auto"]
+        else:
+            args += ["--raw-bw", ""]   # explicit disable

-        # If the user left the default generic name, replace with a timestamped one
-        # so each session gets its own file.
-        if raw_bw:
-            if os.path.basename(raw_bw) in ("raw_bw.bin", "raw_bw"):
-                raw_bw = os.path.join(os.path.dirname(raw_bw) or logdir, f"raw_bw_{ts}.bin")
-                self.raw_bw_var.set(raw_bw)
-            args += ["--raw-bw", raw_bw]
-        if raw_s3:
-            if os.path.basename(raw_s3) in ("raw_s3.bin", "raw_s3"):
-                raw_s3 = os.path.join(os.path.dirname(raw_s3) or logdir, f"raw_s3_{ts}.bin")
-                self.raw_s3_var.set(raw_s3)
-            args += ["--raw-s3", raw_s3]
+        if self.raw_s3_enabled.get():
+            args += ["--raw-s3", raw_s3_explicit if raw_s3_explicit else "auto"]
+        else:
+            args += ["--raw-s3", ""]   # explicit disable

        try:
            self.process = subprocess.Popen(
@@ -390,8 +390,14 @@ def main() -> int:
    ap.add_argument("--s3", default="COM5", help="S3-side COM port (default: COM5)")
    ap.add_argument("--baud", type=int, default=38400, help="Baud rate (default: 38400)")
    ap.add_argument("--logdir", default=".", help="Directory to write session logs into (default: .)")
-    ap.add_argument("--raw-bw", default=None, help="Optional file to append raw bytes sent from BW->S3 (no headers)")
-    ap.add_argument("--raw-s3", default=None, help="Optional file to append raw bytes sent from S3->BW (no headers)")
+    ap.add_argument("--raw-bw", default="auto",
+                    help="File to append raw bytes sent from BW->S3 (no headers). "
+                         "Default 'auto' generates a timestamped name in --logdir. "
+                         "Pass an empty string to disable.")
+    ap.add_argument("--raw-s3", default="auto",
+                    help="File to append raw bytes sent from S3->BW (no headers). "
+                         "Default 'auto' generates a timestamped name in --logdir. "
+                         "Pass an empty string to disable.")
    ap.add_argument("--quiet", action="store_true", help="No console heartbeat output")
    ap.add_argument("--status-every", type=float, default=0.0, help="Seconds between console heartbeat lines (default: 0 = off)")
    args = ap.parse_args()
@@ -414,12 +420,16 @@ def main() -> int:
    # If raw tap flags were passed without a path (bare --raw-bw / --raw-s3),
    # or if the sentinel value "auto" is used, generate a timestamped name.
    # If a specific path was provided, use it as-is (caller's responsibility).
-    raw_bw_path = args.raw_bw
-    raw_s3_path = args.raw_s3
-    if raw_bw_path in (None, "", "auto"):
-        raw_bw_path = os.path.join(args.logdir, f"raw_bw_{ts}.bin") if args.raw_bw is not None else None
-    if raw_s3_path in (None, "", "auto"):
-        raw_s3_path = os.path.join(args.logdir, f"raw_s3_{ts}.bin") if args.raw_s3 is not None else None
+    # Resolve raw tap paths.
+    # "auto" (default) → timestamped file in logdir (always captured).
+    # Explicit path     → use verbatim.
+    # None or ""        → disabled (pass --raw-bw "" to suppress capture).
+    raw_bw_path: Optional[str] = args.raw_bw if args.raw_bw else None
+    raw_s3_path: Optional[str] = args.raw_s3 if args.raw_s3 else None
+    if raw_bw_path == "auto":
+        raw_bw_path = os.path.join(args.logdir, f"raw_bw_{ts}.bin")
+    if raw_s3_path == "auto":
+        raw_s3_path = os.path.join(args.logdir, f"raw_s3_{ts}.bin")

    logger = SessionLogger(log_path, bin_path, raw_bw_path=raw_bw_path, raw_s3_path=raw_s3_path)

@@ -104,8 +104,12 @@
 | 2026-04-11 | §7.11 (NEW) | **NEW — §7.11 Erase-All Protocol added.** Full wire sequence, SUB 0x06 storage range payload layout, post-erase key counter reset (resets to `0x01110000`). Confirmed from 4-11-26 MITM capture of live Blastware ACH session. |
 | 2026-04-11 | §14.6 | **RESOLVED — ACH Session Lifecycle is no longer "Future".** `bridges/ach_server.py` fully implements inbound ACH: POLL handshake, device info, event download. State tracked via `ach_state.json` (key-based, with `max_downloaded_key` for post-erase detection). `--clear-after-download` flag added for the standard delete-after-upload workflow. |
 | 2026-04-17 | §7.6.2, §14 | **RESOLVED — Float 6.206053 at channel_label+28 is the ADC-to-velocity scale factor.** Confirmed from Series III Interface Handbook §4.5 formula: `Range (×1) = 1.61133 V / Sensitivity (V/unit)`. For the standard Instantel geophone at Normal range (10.000 in/s): Sensitivity = 1.61133 / 10 = 0.161133 V/(in/s). The stored value is the **inverse sensitivity** = 1/0.161133 = **6.206053 (in/s)/V**. Cross-check: 1.61133 V × 6.206053 = 10.000 in/s ✅. The firmware uses it as: `PPV (in/s) = ADC_voltage (V) × 6.206053`. Value is identical on all Instantel standard geophones — it is a hardware/firmware constant, NOT a user-configurable setting. Do NOT write this field. Open question §14 item "Max Geo Range float 6.2061" is now **RESOLVED**. |
-| 2026-04-20 | §7.6.4 (NEW), §7.9, Appendix B | **CONFIRMED — Recording Mode byte location.** Three targeted captures (4-20-26) confirmed `recording_mode` at **`cfg[5]`** in the SUB 71 write payload (3-chunk compliance write). Method: single Blastware session, one initial E5 config pull, then three sequential "Send to unit" writes changing Recording Mode only. Diff of SUB 71 chunk-1 payloads: only `cfg[5]` and `cfg[1024]` changed; `cfg[1024]` delta exactly equals `cfg[5]` delta (chunk running checksum). In the E5 read response (sub-frame 1, page=0x0010), the field is at **`data[17]`** (= **anchor − 4** from the 10-byte anchor), one position earlier than in the write payload due to an extra `0x10` byte at `data[18]` present only in the read format. Enum: `0x00`=Single Shot, `0x01`=Continuous, `0x03`=Histogram, `0x04`=Histogram+Continuous. `0x02` value not yet observed. See §7.6.4 for full details. |
+| 2026-04-20 | §7.6.4 (NEW), §7.9, Appendix B | **CONFIRMED — Recording Mode byte location.** Three targeted captures (4-20-26) confirmed `recording_mode` at anchor−8 in both the E5 read payload and the BW write payload (6-byte anchor `\xbe\x80\x00\x00\x00\x00`). BW write payload and E5 read payload are **byte-identical** around the anchor region — Blastware round-trips the wire-encoded E5 bytes verbatim with only the target field modified. Anchor position varies by ±1 depending on whether recording_mode = 0x03 (Histogram), because E5 wire-encodes `0x03` as the inner DLE+ETX pair `\x10\x03` (2 bytes), which S3FrameParser preserves as two literal bytes in `compliance_raw`. Enum: `0x00`=Single Shot, `0x01`=Continuous, `0x03`=Histogram, `0x04`=Histogram+Continuous. `0x02` value not yet observed. The byte at anchor−9 is `0x00` for Single Shot / Continuous, and `0x10` for Histogram (DLE prefix from E5 encoding) and Histogram+Continuous (actual config byte). See §7.6.4 for full details. |
+| 2026-04-21 | Appendix D (NEW) | **NEW — Blastware .N00 and .MLG file formats fully decoded.** `minimateplus/blastware_file.py` implements `write_n00()` and `write_mlg()`. N00 file format confirmed: 22B header + 21B STRT record + variable body + 26B footer. Body reconstructed from A5 bulk waveform stream frames with per-frame skip amounts (probe=7+strt_pos+21, A5[1]=13, A5[2+]=12, terminator=11) and DLE strip rule (strip `0x10` before `{0x02,0x03,0x04}`, keep following byte). Footer extracted verbatim from terminator frame's last 26 bytes. Split-pair edge case: when `frame.data[-1]==0x10` and `chk_byte∈{0x02,0x03,0x04}`, reunite both bytes before stripping and always remove trailing chk_byte (`stripped[:-1]`) — chk_byte is checksum, not payload. STRT record must be copied verbatim from A5[0]; bytes [10:20] are device-specific and cannot be reconstructed from Event fields. `write_n00` verified byte-perfect against `M529LIY6.N00` from 4-3-26-multi_event capture. MLG format: 308B header + N×292B records; CRC algorithm unknown (write as 0x0000). |
+| 2026-04-21 | Appendix D §D.5 (NEW) | **NEW — Blastware filename encoding fully decoded.** Serial prefix: `chr(ord('B') + floor(serial/1000))` + last 3 digits zero-padded. Stem: 4-char base-36 of `floor(total_seconds/1296)`. Extension: `AB0` for manual/direct downloads (3 chars), `AB0W` or `AB0H` for ACH/call-home downloads (4 chars), where `AB` = 2-char base-36 of `total_seconds % 1296` and W/H = waveform/histogram. Epoch = 1985-01-01 00:00:00 device local time. Confirmed against 3,248 files from 10-year production archive with zero errors. 3-day cycle property: same daily recording time cycles through 3 extensions (864s/day shift, period=3 days). `blastware_filename(event, serial, ach=False)` implements full formula. |
+| 2026-04-21 | §7.6.2, §5.3 | **CORRECTED — compliance_raw contains wire-encoded bytes, NOT logical bytes.** S3FrameParser appends DLE+ETX inner-frame pairs as two literal bytes to the frame body. Any `0x03` values in the compliance config appear in `compliance_raw` as `\x10\x03` (two bytes), not as a single `0x03`. The previous claim "S3FrameParser handles this transparently so compliance_raw contains logical (destuffed) bytes" was wrong. Consequence: `compliance_raw` is the wire-encoded E5 payload; anchor-relative reads work correctly because the anchor position automatically accounts for any DLE-encoded bytes before it. For write-back, round-tripping `compliance_raw` verbatim sends the correct wire bytes to the device. **DLE ETX escaping in write frames:** Blastware escapes `0x03` bytes in write frame data as `\x10\x03` on wire; our `build_bw_write_frame` does not (writes data raw). Device is confirmed to accept raw writes for all tested modes — likely uses the offset/length field for write frame framing, not ETX scanning. |
 | 2026-04-20 | §7.6.2, §7.9, Appendix B | **CONFIRMED — Geophone maximum range / sensitivity selector byte location.** Two targeted captures (4-20-26, geo sensitivity folder): one at Normal 10.000 in/s, one at Sensitive 1.250 in/s. E5 read payload diff: exactly 3 bytes differ at channel_label+33 for Tran/Vert/Long. Values: `0x00`=Normal 10.000 in/s, `0x01`=Sensitive 1.250 in/s. Same offset applies to the SUB 71 write payload (which is the same 2126-byte E5-format buffer round-tripped verbatim). **`channel_label+20` reads `0x01` in ALL captures regardless of range setting — it is NOT this field.** Previous hypothesis (uint8 at Tran+20, 0x01=Normal) was WRONG. Stored as `geo_range` in `ComplianceConfig`. Encoded to all three geo channel blocks (Tran/Vert/Long) at label+33. |
+| 2026-04-20 | §5.1, §5.3, §7.12 (NEW) | **NEW — Auto Call Home config protocol confirmed from 4-20-26 call home settings captures.** SUB 0x2C (Call Home Config READ, response 0xD3, data offset 0x7C=124) and SUB 0x7E/0x7F (WRITE + CONFIRM, response 0x81/0x80) confirmed. Write payload = read payload (125 bytes) + `\x00\x00` (127 bytes total). **DLE-escaped ETX at raw[117:119]:** the device returns logical value 0x03 (num_retries=3) as `\x10\x03` on the wire — S3FrameParser preserves both bytes as two literals, causing a +1 byte shift for all subsequent fields. Write frame sends these bytes verbatim (device interprets `\x10\x03` as literal value 3). Field map confirmed from 10-frame BW TX diff. See §7.12 for full layout. |

 ---

@@ -267,6 +271,7 @@ Step 4 — Device sends actual data payload:
 | `1C` | **MONITOR STATUS READ** | Two-step read, data offset 0x2C (44 bytes). `section[1] == 0x10` → monitoring; `0x00` → idle (CONFIRMED 2026-04-09, 100% accuracy on 144 frames). Payload length: 46–47 bytes IDLE, 48–49 bytes MONITORING. `frame.data` has checksum stripped — no trailing byte to skip. Battery/memory at end: `section[-10:-8]` = battery×100 (uint16 BE), `section[-8:-4]` = memory_total (uint32 BE), `section[-4:]` = memory_free (uint32 BE). | ✅ CONFIRMED 2026-04-09 |
 | `96` | **START MONITORING** | Single write frame, no data payload. Transitions unit from idle to monitoring mode (after optional on-device sensor check ~40 s). | ✅ CONFIRMED 2026-04-08 |
 | `97` | **STOP MONITORING** | Single write frame, no data payload. Stops monitoring, unit returns to idle. | ✅ CONFIRMED 2026-04-08 |
+| `2C` | **CALL HOME CONFIG READ** | Two-step read, data offset 0x7C (124 bytes + 1-byte DLE artefact = 125 raw bytes). Returns Auto Call Home configuration: enable flag, dial string, scheduled call times, retry settings, modem timing. Response SUB = 0xD3. **DLE note:** logical value 0x03 (num_retries) is returned as `\x10\x03` on the wire, which S3FrameParser preserves as two literal bytes — this shifts all subsequent field positions by +1. See §7.12 for full field map. | ✅ CONFIRMED 2026-04-20 |
 | `A3` | **ERASE ALL BEGIN** | Single frame, token=0xFE at params[7]. Initiates device memory erase. Must be followed by 0x1C probe+data + 0x06 probe+data + 0xA2 to complete. Standard `build_bw_frame` (not write-format). Response ack SUB = 0x5C. | ✅ CONFIRMED 2026-04-11 |
 | `A2` | **ERASE ALL CONFIRM** | Single frame, token=0xFE at params[7]. Commits the erase initiated by 0xA3. After this ack (SUB 0x5D), device memory is cleared and the event counter resets to `0x01110000`. | ✅ CONFIRMED 2026-04-11 |

@@ -296,6 +301,7 @@ All requests use CMD byte `0x02`. All responses use CMD byte `0x10 0x02` (which,
 | `98` | `67` | ✅ CONFIRMED 2026-04-08 |
 | `96` | `69` | ✅ CONFIRMED 2026-04-08 |
 | `97` | `68` | ✅ CONFIRMED 2026-04-08 |
+| `2C` | `D3` | ✅ CONFIRMED 2026-04-20 |
 | `A3` | `5C` | ✅ CONFIRMED 2026-04-11 |
 | `A2` | `5D` | ✅ CONFIRMED 2026-04-11 |

@@ -317,6 +323,8 @@ Write commands are initiated by Blastware (`BW->S3`) and use SUB bytes in the `0
 | `72` | **WRITE CONFIRM A** | Short frame, no data. Likely commit/confirm step after `71`. | `8D` | ✅ CONFIRMED |
 | `73` | **WRITE CONFIRM B** | Short frame, no data. | `8C` | ✅ CONFIRMED |
 | `74` | **WRITE CONFIRM C** | Short frame, no data. | `8B` | ✅ CONFIRMED |
+| `7E` | **CALL HOME CONFIG WRITE** | Writes Auto Call Home configuration (127 bytes: 125-byte read payload + `\x00\x00`). Offset = data[1]+2 = 0x7E. Write format (DLE-aware checksum, only BW_CMD `0x10` doubled on wire). Response SUB = 0x81. Must be followed by SUB 0x7F confirm. | `81` | ✅ CONFIRMED 2026-04-20 |
+| `7F` | **CALL HOME WRITE CONFIRM** | Short frame, no data. Commits call home config write from SUB 0x7E. Response SUB = 0x80. | `80` | ✅ CONFIRMED 2026-04-20 |
 | `82` | **TRIGGER CONFIG WRITE** | Writes trigger config block (0x1C bytes, mirrors SUB `1C` read). | `7D` | ✅ CONFIRMED |
 | `83` | **TRIGGER WRITE CONFIRM** | Short frame, no data. Likely commit step after `82`. | `7C` | ✅ CONFIRMED |

@@ -330,6 +338,8 @@ Write commands are initiated by Blastware (`BW->S3`) and use SUB bytes in the `0
 | `72` | `8D` |
 | `73` | `8C` |
 | `74` | `8B` |
+| `7E` | `81` |
+| `7F` | `80` |
 | `82` | `7D` |
 | `83` | `7C` |

@@ -1221,26 +1231,52 @@ Two critical differences from `build_bw_frame`:
 | Frame | offset_word | counter | params | Purpose |
 |---|---|---|---|---|
 | Probe | `0x1004` | `0x0000` | 10 bytes (`bulk_waveform_params(0)`) | Initiate transfer |
-| Chunk 1 | `0x1004` | `0x0400` | 11 bytes | First data chunk |
-| Chunk 2 | `0x1004` | `0x0800` | 11 bytes | Second chunk |
-| Chunk N | `0x1004` | `N * 0x0400` | 11 bytes | Nth chunk |
+| Chunk 1 | `0x1004` | `max(key4[2:4], 0x0400)` | 11 bytes | First data chunk |
+| Chunk 2 | `0x1004` | `max(key4[2:4], 0x0400) + 0x0400` | 11 bytes | Second chunk |
+| Chunk N | `0x1004` | `max(key4[2:4], 0x0400) + (N-1) * 0x0400` | 11 bytes | Nth chunk |
 | … | … | … | … | … |
-| Termination | `0x005A` | `last + 0x0400` | 10 bytes | End transfer |
+| Termination | `0x005A` | `max(key4[2:4], 0x0400) + N * 0x0400` | 10 bytes | End transfer |

-> ⚠️ **2026-04-06 CORRECTED — chunk counter is monotonic for ALL chunks.**
-> The 4-2-26 BW TX capture showed counter=0x1004 for chunk 1, which was hardcoded as a
-> special case. This was a Blastware artifact. Empirically confirmed: counter=0x0400 for
-> chunk 1 works correctly; counter=0x1004 causes the device to time out. The device does
-> NOT strictly validate the counter value — it streams data for any valid 5A request for
-> the given key. Use `chunk_num * 0x0400` (monotonic) for all chunks.
-> BW's true internal formula is `key4[2:4] + n * 0x0400`. For event 1 (key `01110000`)
-> this equals `n * 0x0400` since `key4[2:4] = 0x0000`. The monotonic formula is correct
-> for all keys encountered on this device.
+> ⚠️ **2026-04-06 CORRECTED — chunk counter is `key4[2:4] + (N-1) * 0x0400`.**
+> The 4-2-26 BW TX capture showed counter=0x1004 for chunk 1 of key `01110000`, leading to
+> an interim "monotonic n * 0x0400" formula.  This was accidentally correct because
+> `key4[2:4] == 0x0000` for that event.
+>
+> **2026-04-24 CORRECTION:** The counter is an absolute circular-buffer address.
+> BW's true formula is `key4[2:4] + (chunk_num - 1) * 0x0400` where `key4[2:4]` is the
+> event's storage base offset (`(key4[2]<<8) | key4[3]`).  For keys where
+> `key4[2:4] != 0x0000` (e.g. key `01111884`), using `n * 0x0400` sends requests into the
+> wrong buffer region — the device returns data from a completely different event.
+>
+> **2026-04-26 FINAL CORRECTION:** The formula `key4[2:4] + (N-1) * 0x0400` is wrong when
+> `key4[2:4] == 0x0000` (e.g. event key `01110000`, the very first event after a device erase).
+> Counter=0x0000 for chunk 1 is the same address as the probe frame — the device re-returns
+> the STRT record data instead of waveform payload (frame 1 has len=1097, same as probe, and
+> contains `b"STRT\xff\xfe"`, contributing zero waveform bytes).
+> Final formula: `max(key4[2:4], 0x0400) + (chunk_num - 1) * 0x0400`.
+> For key `01110000`: chunk 1 = 0x0400 (confirmed working, empirical test 2026-04-06).
+> For key `0111245a`: chunk 1 = 0x245a (unchanged, confirmed from 4-3-26 capture).

 The `stop_after_metadata=True` flag causes the loop to stop as soon as `b"Project:"` is
-found in the accumulated A5 frame data, typically after 7–9 chunks.  A termination frame
+found in the accumulated A5 frame data, typically after 4–9 chunks.  A termination frame
 is always sent before returning.

+**IMPORTANT — one extra chunk required after "Project:" for valid file footer (confirmed 2026-04-23):**
+When writing a Blastware-compatible waveform file, stopping immediately at "Project:" and
+sending termination produces an empty termination response with no footer bytes (`0e 08`
+marker missing).  Blastware downloads exactly **one more chunk** after finding "Project:"
+before sending termination — that extra chunk primes the device to return valid footer
+bytes (monitoring start/stop timestamps) in the termination response.
+
+`read_bulk_waveform_stream(stop_after_metadata=True)` implements this: after the "Project:"
+chunk is received, one additional chunk is requested before breaking.  The termination
+response (`include_terminator=True`) then contains the correct `0e 08` footer.
+
+**do NOT use `full_waveform=True` for Blastware file writing** — for events with long
+post-event silence (35 chunks), the silence chunks contain embedded device-internal
+pointer structures that produce spurious STRT markers in the file body.  Blastware only
+downloads 4–5 chunks (metadata + one signal chunk) regardless of event length.
+
 #### 7.8.3 A5 Frame Layout

 Each A5 response frame contains a chunk of raw bulk data. Frame 7 of the stream carries the
@@ -1522,6 +1558,117 @@ and applies this heuristic on every call-home.

 ---

+### 7.12 Auto Call Home Config (SUB 0x2C / 0x7E / 0x7F) — ✅ CONFIRMED 2026-04-20
+
+> Confirmed from `bridges/captures/4-20-26/call home settings/` — 10 BW TX write frames
+> diffed against the S3 read payload. Accessible in Blastware via Remote Access → Setup Unit.
+
+#### 7.12.1 Read Protocol — SUB 0x2C → Response 0xD3
+
+Standard two-step read:
+
+| Step | Offset | Purpose |
+|---|---|---|
+| Probe | `0x0000` | Get ack (no data returned) |
+| Data | `0x007C` (124) | Receive 125-byte raw payload |
+
+`DATA_LENGTHS[SUB_CALL_HOME] = 0x7C`
+
+The raw payload is accessed as `data_rsp.data[11:]` — this is 125 bytes (not 124) because
+the device returns logical value 0x03 (num_retries=3) as the two-byte wire sequence
+`\x10\x03`. S3FrameParser is in `STATE_IN_FRAME` when it sees `0x10`, transitions to
+`STATE_AFTER_DLE`, and then on `0x03` (ETX qualifier) it would normally end the frame —
+but in the `_IN_FRAME_DLE` state it instead appends **both** the `0x10` and the `0x03`
+literally to the payload. The result: `raw[117] = 0x10`, `raw[118] = 0x03`, and all
+subsequent fields are shifted +1 from their logical positions.
+
+#### 7.12.2 Raw Payload Field Map (125 bytes, from `data_rsp.data[11:]`)
+
+> All offsets are into the 125-byte raw array. Offsets ≥ 119 are shifted +1 from logical
+> due to the DLE-escaped 0x03 at raw[117:119].
+
+| Raw Offset | Field | Type | Notes |
+|---|---|---|---|
+| `[5]` | `auto_call_home_enabled` | uint8 | `0x00` = disabled, `0x01` = enabled |
+| `[6:46]` | `dial_string` | ASCII | 40-byte null-padded, e.g. `"12345"` or phone number |
+| `[87]` | `after_event_recorded` | uint8 | `0x00` = off, `0x01` = on |
+| `[91]` | `at_specified_times` | uint8 | `0x00` = off, `0x01` = on |
+| `[93]` | `time1_enabled` | uint8 | `0x00` = off, `0x01` = on |
+| `[101]` | `time1_hour` | uint8 | 0–23 |
+| `[102]` | `time1_min` | uint8 | 0–59 |
+| `[95]` | `time2_enabled` | uint8 | `0x00` = off, `0x01` = on |
+| `[105]` | `time2_hour` | uint8 | 0–23 |
+| `[106]` | `time2_min` | uint8 | 0–59 |
+| `[117]` | DLE prefix `0x10` | — | Part of `\x10\x03` wire encoding for num_retries value 3 |
+| `[118]` | `num_retries` (value = 3) | uint8 | Logical value 0x03; check `raw[117] == 0x10` to detect DLE prefix |
+| `[120]` | `time_between_retries_sec` | uint8 | Shift +1 from logical 119 |
+| `[122]` | `wait_for_connection_sec` | uint8 | Shift +1 from logical 121 |
+| `[124]` | `warm_up_time_sec` | uint8 | Shift +1 from logical 123 |
+
+**Unconfirmed fields** (offsets not yet mapped from captures):
+- Time slots 3 and 4 (if they exist — Blastware UI only shows 2 time slots in observed sessions)
+- `modem_power_relay_enabled` (bool)
+- `storage_mode` (call home trigger on all events vs. triggered only?)
+
+#### 7.12.3 DLE-Escaped 0x03 — Critical Detail
+
+The `\x10\x03` sequence at raw[117:119] is **not** a DLE stuffing artifact in the usual
+sense. Standard DLE stuffing escapes `\x10` → `\x10\x10`. But here the device is encoding
+the integer value `3` in a position where the byte `\x03` would be indistinguishable from
+the frame ETX terminator. The device therefore sends `\x10\x03` (DLE + ETX = "inner-frame
+terminator" in S3 inner-frame syntax). S3FrameParser correctly handles this: in
+`STATE_AFTER_DLE`, seeing `\x03` (ETX) while **inside** an outer frame causes it to
+append both `\x10` and `\x03` as literal bytes rather than ending the frame. The outer
+frame only terminates on a **bare** `\x03` (without the DLE prefix).
+
+The write frame sends these bytes verbatim — the device accepts `\x10\x03` in the write
+payload and interprets it as the value 3. No transformation is needed in
+`_encode_call_home_config()`.
+
+**Limitation:** Any field that needs to encode the value `3` (0x03) requires this DLE
+prefix. The current encoder raises `ValueError` if any hour or minute field equals 3,
+since the encoder does not yet implement DLE-prefixed writes for arbitrary field positions.
+In practice, 3:00 AM / 3 minutes past are unlikely scheduled call times.
+
+#### 7.12.4 Write Protocol — SUB 0x7E → 0x7F
+
+Write format (same as other write commands — only BW_CMD `0x10` doubled on wire;
+all other bytes written raw; DLE-aware checksum):
+
+| Step | SUB | Payload | Offset | Response |
+|---|---|---|---|---|
+| Data write | `0x7E` | 127 bytes (125-byte read payload + `\x00\x00`) | `data[1]+2 = 0x7E` (126) | `0x81` |
+| Confirm | `0x7F` | empty | `0x00` | `0x80` |
+
+**Write payload construction:**
+```python
+write_payload = bytearray(raw_125_bytes)
+write_payload.append(0x00)
+write_payload.append(0x00)
+# patch fields in-place, then pass bytes(write_payload) to build_bw_write_frame
+```
+
+**Offset formula:**  `write_payload[1] = 0x7C` (same as DATA_LENGTH).
+`offset = write_payload[1] + 2 = 0x7C + 2 = 0x7E = 126`.
+This follows the identical pattern as SUB 0x68 (event index write) and SUB 0x69 (waveform write).
+
+**No preceding 0x2C read required** — Blastware sends SUB 0x7E directly using cached
+state. The `seismo-relay` implementation always reads first (`get_call_home_config()`)
+before writing for safety.
+
+#### 7.12.5 Implementation Notes
+
+- `MiniMateProtocol.read_call_home_config()` — standard two-step read; returns `data_rsp.data[11:]` (125 bytes raw)
+- `MiniMateProtocol.write_call_home_config(data)` — sends SUB 0x7E (127-byte payload) then SUB 0x7F confirm
+- `MiniMateClient.get_call_home_config()` → `CallHomeConfig` dataclass
+- `MiniMateClient.set_call_home_config(...)` — reads current config, patches via `_encode_call_home_config()`, writes back
+- `_decode_call_home_config(raw)` — handles DLE prefix detection at raw[117]
+- `_encode_call_home_config(raw, ...)` — patches in-place, appends 2 trailing zeros; raises `ValueError` if any hour/min == 3
+- REST API: `GET /device/call_home` and `POST /device/call_home` in `sfm/server.py`
+- Web UI: "Call Home" tab in `sfm/sfm_webapp.html`
+
+---
+
 ## 8. Timestamp Format

 Two timestamp wire formats are used:
@@ -2126,6 +2273,279 @@ Semantic Interpretation           <- settings, events, responses

 ---

+---
+
+## Appendix D — Blastware Binary File Formats (.N00 / .MLG / others)
+
+> ✅ CONFIRMED 2026-04-21 — all fields verified by binary diff of reconstructed vs reference
+> files from the 4-3-26-multi_event capture (M529LIY6.N00, BE11529.MLG).
+>
+> ⚠️ EXTENSION MAPPING REFUTED 2026-04-21 — earlier assumption that extension encodes
+> recording mode is **FALSE**. A continuous-mode event produced `.EI0`, not `.9T0`.
+> Extension encoding algorithm is unknown. Do not use extension to infer recording mode.
+
+### D.1 Common File Header (22 bytes)
+
+All Blastware files (regardless of type) share an 18-byte prefix followed by a 4-byte type tag.
+
+| Offset | Length | Value | Description |
+|---|---|---|---|
+| 0x00 | 6 | `10 00 01 80 00 00` | Fixed prefix |
+| 0x06 | 10 | `Instantel\x00` | ASCII string |
+| 0x10 | 2 | `07 2c` | Fixed suffix |
+| 0x12 | 4 | varies | File type tag (see below) |
+
+**Total header: 22 bytes.**
+
+**Type tags:**
+
+| Extension | Type tag | Description |
+|---|---|---|
+| `.N00` | `00 12 03 00` | Waveform event (confirmed) |
+| `.9T0` | `00 12 03 00` | Waveform event — same type tag as .N00 (assumed; not independently confirmed) |
+| `.EI0` | `00 12 03 00` | Waveform event — same type tag (assumed; continuous-mode event observed 2026-04-21) |
+| `.MLG` | `22 01 0e a0` | Monitor log |
+
+**Extension encoding — new firmware (V10.72+) FULLY DECODED (confirmed 2026-04-22):**
+
+The extension differs depending on how the file was saved:
+
+| Download method | Extension format | Example |
+|---|---|---|
+| Manual / direct (Blastware connected to unit) | `AB0` (3 chars) | `.CE0` |
+| Call-home / ACH | `AB0W` or `AB0H` (4 chars) | `.CE0H` |
+
+Where:
+- `AB` = 2-char base-36 of `total_seconds % 1296`; `A = value // 36`, `B = value % 36`
+- `total_seconds = (event_local_time − 1985-01-01T00:00:00_local)` in seconds
+- `0` = always literal digit zero
+- `W` = Full Waveform, `H` = Full Histogram (ACH only)
+
+Base-36 alphabet: `0–9` = 0–9, `A–Z` = 10–35.
+
+The 10-year production archive contains only ACH files (all end in W or H). Manual Blastware downloads produce the same `AB0` prefix but without the trailing type character.
+
+**3-day cycle property (confirmed 2026-04-22):** A unit recording at a fixed daily time cycles through exactly **3 different extensions** with a 3-day period. Each calendar day shifts `total_seconds % 1296` by 864 (since `86400 % 1296 = 864`). The cycle repeats every 3 days because `gcd(1296, 864) = 432`. Confirmed from archive: top 3 extensions `CE0H` (95), `0E0H` (93), `OE0H` (91) are the 3-day cycle of a 06:00:14 daily call-in (seconds-in-window = 446, 14, 878).
+
+**B character invariance:** `864 = 24 × 36`, so adding one day never changes `value % 36` — the second extension character is invariant for a fixed daily recording time. Only the first character cycles through 3 values.
+
+**Old firmware (S338):** 3-char extensions observed (`.N00`, `.EI0`, etc.) — may simply be manual downloads under the same AB0 scheme, or a different encoding. Not yet confirmed.
+
+**Micromate Series 4** uses a different extension format (observed: `IDFH`, `IDFW`). This formula does NOT apply to Micromate units.
+
+All waveform files share the same `00 12 03 00` type tag regardless of extension. Blastware identifies file type by extension, not by type tag alone.
+
+### D.2 Timestamp Encoding (Blastware files)
+
+All timestamps in N00 and MLG files use an **8-byte big-endian format**:
+
+| Byte | Field |
+|---|---|
+| 0 | day (uint8) |
+| 1 | month (uint8) |
+| 2–3 | year (uint16 BE) |
+| 4 | `0x00` (reserved) |
+| 5 | hour (uint8) |
+| 6 | minute (uint8) |
+| 7 | second (uint8) |
+
+Example: `01 04 07 ea 00 00 1c 08` → April 1, 2026, 00:28:08.
+
+Note: this differs from the 8-byte protocol timestamp (`[day][sub_code][month][year_HI][year_LO][0x00][hour][min][sec]` = 9 bytes) used in the device's on-wire 0C waveform records. The file format uses a compact 8-byte layout without the `sub_code` byte.
+
+### D.3 N00 File Format — Single-Shot Waveform Event
+
+**File layout:** `[22B header] [21B STRT record] [body bytes] [26B footer]`
+
+#### D.3.1 STRT Record (21 bytes)
+
+The STRT record immediately follows the 22-byte header.
+
+| Offset | Length | Field | Notes |
+|---|---|---|---|
+| 0 | 4 | `STRT` | ASCII literal |
+| 4 | 2 | `ff fe` | Fixed |
+| 6 | 4 | event key (key4) | 4-byte waveform key |
+| 10 | 4 | device-specific | NOT a repeat of key4 — device-internal field |
+| 14 | 6 | device-specific | NOT zero-padded — device-internal fields |
+| 20 | 1 | rectime | uint8 seconds |
+
+**Critical:** The STRT record must be copied verbatim from A5[0].data[7+strt_pos:] — bytes [10:20] contain device-specific values that cannot be reconstructed from protocol-level Event fields alone.
+
+#### D.3.2 Body Bytes (variable)
+
+The body is reconstructed from the raw A5 bulk waveform stream frames by stripping DLE framing markers and taking the appropriate slice of each frame's data section.
+
+**Per-frame contribution (from `frame.data`):**
+
+| Frame | Skip amount | Notes |
+|---|---|---|
+| A5[0] (probe) | `7 + strt_pos_in_w0 + 21` | Skip frame.data prefix + STRT record |
+| A5[1] | 13 | 7-byte prefix + 6-byte first-chunk header |
+| A5[2..N] | 12 | 7-byte prefix + 5-byte chunk header |
+| Terminator (page_key=0x0000) | 11 | 7-byte prefix + 4-byte terminator header |
+
+**DLE strip rule:** For each frame's contribution (`frame.data[skip:]`), strip any `0x10` byte immediately followed by `0x02`, `0x03`, or `0x04`. Only the `0x10` is stripped; the following byte is kept as payload.
+
+**Split-pair edge case:** When `frame.data[-1] == 0x10` AND `frame.chk_byte ∈ {0x02, 0x03, 0x04}`, the S3FrameParser split a DLE+XX pair at the payload/checksum boundary. Reunite the bytes before stripping (`relevant + bytes([chk_byte])`), then always remove the trailing chk_byte from the result (`stripped[:-1]`) — chk_byte is the wire checksum, never payload.
+
+**Body/footer split:** Accumulate all frame contributions (data frames + terminator) into `all_bytes`. Then:
+- `body = all_bytes[:-26]` (variable length)
+- `footer = all_bytes[-26:]` (always 26 bytes — extracted from terminator content)
+
+#### D.3.3 Footer (26 bytes)
+
+The footer terminates the N00 file. Its bytes come directly from the terminator A5 frame's inner content — do NOT reconstruct from event metadata.
+
+| Offset | Length | Field | Notes |
+|---|---|---|---|
+| 0 | 2 | `0e 08` | Fixed marker |
+| 2 | 8 | ts1 | Start timestamp (8B big-endian) |
+| 10 | 8 | ts2 | Stop timestamp (8B big-endian) |
+| 18 | 6 | `00 01 00 02 00 00` | Fixed |
+| 24 | 2 | CRC | 2-byte CRC — algorithm unconfirmed |
+
+**CRC:** The 2-byte CRC at footer[24:26] has an unconfirmed algorithm. In M529LIY6.N00 it reads `fe da`. Attempts to match CRC-16/CCITT, CRC-16/IBM, CRC-32 (truncated), and 40+ polynomial/init combinations all failed. The writer copies it verbatim from the terminator frame.
+
+### D.4 MLG File Format — Monitor Log
+
+**File layout:** `[308B header] [N × 292B records]`
+
+#### D.4.1 MLG Header (308 bytes)
+
+| Offset | Length | Field | Notes |
+|---|---|---|---|
+| 0x00 | 22 | common header | prefix + `22 01 0e a0` type tag |
+| 0x16 | 16 | unknown | observed as zeros in BE11529.MLG |
+| 0x2A | 8 | serial number | null-padded ASCII (e.g. `"BE11529"`) |
+| 0x32 | remainder | zero pad | pads to 308 bytes total |
+
+#### D.4.2 MLG Record (292 bytes each)
+
+| Offset | Length | Field | Notes |
+|---|---|---|---|
+| 0 | 2 | CRC | 2-byte CRC — algorithm unconfirmed; write as `00 00` |
+| 2 | 4 | `22 01 0e 80` | Record marker |
+| 6 | 8 | ts1 | Start timestamp (8B big-endian) |
+| 14 | 8 | ts2 | Stop timestamp (8B big-endian); zeros if no stop |
+| 22 | 4 | flags | Record type flags (see below) |
+| 26 | 10 | serial | Null-padded ASCII serial number |
+| 36 | variable | text | Type-dependent content |
+| — | remainder | zero pad | pads to 292 bytes total |
+
+**Record flags:**
+
+| Value | Meaning |
+|---|---|
+| `ff ff 00 00` | Monitoring start with no stop recorded |
+| `01 00 02 00` | Triggered event (has ts1 + ts2) |
+| `02 00 00 00` | Monitoring interval (has ts1 + ts2) |
+
+**Text content for triggered events (`flags = 01 00 02 00`):**
+
+| Byte | Field |
+|---|---|
+| 0 | `0x08` |
+| 1–8 | ts1 copy (8B big-endian) |
+| 9+ | `"Geo: X.XXX in/s\x00"` ASCII geo threshold |
+
+#### D.4.3 MLG CRC
+
+The 2-byte CRC at record[0:2] uses an unconfirmed algorithm. Tested against CRC-16/CCITT, CRC-16/IBM, CRC-32 (truncated), word sums, XOR variants, and 40+ polynomial/init combinations — none matched. The writer emits `00 00`. Blastware may reject files with incorrect CRCs (impact on import unknown — TODO: test).
+
+### D.5 Filename Encoding ✅ PARTIALLY CONFIRMED 2026-04-22
+
+Blastware assigns waveform filenames of the form `<prefix_letter><serial3><stem><ext>`, where:
+
+#### D.5.1 Serial Prefix ✅ CONFIRMED 2026-04-22
+
+The first 4 characters of the filename encode the full device serial number:
+
+```
+prefix_letter = chr(ord('B') + floor(serial_numeric / 1000))
+serial3       = f"{serial_numeric % 1000:03d}"   (last 3 digits, zero-padded)
+```
+
+Where `serial_numeric` is the integer after the "BE" device-type prefix.
+
+Examples (all confirmed from archive):
+
+| Serial | serial_numeric / 1000 | prefix_letter | serial3 | Filename prefix |
+|--------|----------------------|---------------|---------|-----------------|
+| BE6907 | 6 | H | 907 | H907 |
+| BE7145 | 7 | I | 145 | I145 |
+| BE11529 | 11 | M | 529 | M529 |
+| BE14036 | 14 | P | 036 | P036 |
+| BE17353 | 17 | S | 353 | S353 |
+| BE18003 | 18 | T | 003 | T003 |
+| BE18191 | 18 | T | 191 | T191 |
+| BE18676 | 18 | T | 676 | T676 |
+
+**Interpretation:** The prefix letter encodes the production generation (batch of 1000 units). B=generation 0 (serials 0–999), C=generation 1 (1000–1999), etc. No units with prefix A have been observed — the earliest known units start around serial 2000+ (prefix D).
+
+**Note:** The "BE" device-type prefix is implicit. The filename only encodes the numeric part of the serial. Other Instantel device types (Micromate, Blastmate) may use a different scheme.
+
+#### D.5.2 Stem + Extension — full timestamp encoding ✅ FULLY CONFIRMED 2026-04-22
+
+The stem (4 chars) and AB extension (2 chars) together form a 6-digit base-36 number encoding a complete second-resolution timestamp:
+
+```python
+total_seconds = stem_int * 1296 + ab_int
+event_local_time = datetime(1985, 1, 1) + timedelta(seconds=total_seconds)
+```
+
+- **Epoch:** `1985-01-01 00:00:00` **device local time** ✅ CONFIRMED — verified against 3,248 files from a 10-year production archive; zero errors (only 2 mismatches were Micromate `IDFH`/`IDFW` files which use a completely different naming scheme)
+- **Unit:** 1296 seconds = 36² ≈ 21.6 minutes per stem increment
+- **Alphabet:** `"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"` (digits then uppercase letters)
+- **Collision:** Events within the same 21.6-minute window share a stem; extension distinguishes them
+
+**Decoding example — `P036L318.C80H` (BE14036, Full Histogram):**
+```
+stem  L318 = 21×36³ + 3×36² + 1×36 + 8 = 983,708
+AB    C8   = 12×36  + 8               =     440
+total_sec  = 983,708 × 1296 + 440     = 1,274,886,008
+event_time = 1985-01-01 + 1,274,886,008s = 2025-05-26 15:00:08 local
+```
+
+**Note on local time:** The device's onboard clock is set to the local timezone of the deployment site. The epoch and all timestamps are in that same local time — there is no UTC conversion. Files moved between timezones will decode to the original deployment timezone.
+
+#### D.5.3 Extension taxonomy
+
+Third character of extension is always `'0'`.  File type is identified by extension, not by the type tag in the header (all waveform extensions share type tag `00 12 03 00`).
+
+| Extension | Recording mode | Sample rate | Status |
+|---|---|---|---|
+| `.N00` | Single Shot (0x00) | 1024 sps | ✅ CONFIRMED |
+| `.9T0` | Continuous (0x01) | 1024 sps | ✅ CONFIRMED |
+| `.490` | ? | ? | ❓ observed from M529LJ8V.490 |
+| `.5K0` | ? | ? | ❓ observed from M529LJDY.5K0 |
+| `.980` | ? | ? | ❓ observed from M529LJDY.980 |
+| `.ML0` | ? | ? | ❓ observed from M529LJDY.ML0 (167s duration; possibly Histogram) |
+
+**Why 5 extensions for "Continuous"?** Binary analysis of all 6 example files shows that `.9T0`, `.490`, `.5K0`, `.980`, `.ML0` are byte-for-byte identical in all metadata regions (compliance anchor block, channel descriptor blocks `Tran/Vert/Long/MicL`). The A5 frame 7 body reflects the **session-start** compliance config, not the per-event capture config. All 5 files show recording_mode=0x01 and sample_rate=1024 in the body. The extension must therefore encode the **capture-time** compliance state — likely a combination of recording mode, sample rate, and possibly mic units or other options. This cannot be determined from file body alone without capture-time compliance data from the 0C record sub_code and the actual waveform sample count.
+
+**DLE-shift offset note for reading recording_mode from N00/9T0 body:**
+
+The compliance block in the file body has been through `_strip_inner_frame_dles`. The 0x10 constant at logical `anchor−7` (between recording_mode and sample_rate_HI) gets stripped when sample_rate_HI = `0x04` (1024 sps), because `0x10` precedes `0x04 ∈ {0x02,0x03,0x04}`. After stripping, the anchor shifts left by 1, so:
+
+| 1024 sps (strip occurs) | 2048 or 4096 sps (no strip) |
+|---|---|
+| `file[anc−7]` = recording_mode | `file[anc−8]` = recording_mode |
+| `file[anc−6:anc−4]` = sample_rate | `file[anc−6:anc−4]` = sample_rate |
+
+For 1024 sps files, the expected file bytes around the anchor are:
+```
+file[anc−9]: mode_prefix (0x00 for Single Shot/Continuous; 0x10 for Histogram)
+file[anc−8]: 0x00 (was recording_mode, but shifted away — now reads 0x00 for mode_prefix)
+file[anc−7]: recording_mode (0x00=Single Shot, 0x01=Continuous, etc.)
+file[anc−6]: 0x04  (sample_rate_HI for 1024 sps)
+file[anc−5]: 0x00  (sample_rate_LO)
+file[anc−4]: histogram_interval_HI
+file[anc−3]: histogram_interval_LO
+```
+
+---
+
 *All findings reverse-engineered from live RS-232 bridge captures.*  
 *Cross-referenced from 2026-03-02 with Instantel MiniMate Plus Operator Manual (716U0101 Rev 15).*  
 *This is a living document — append changelog entries and timestamps as new findings are confirmed or corrected.*
@@ -0,0 +1,949 @@
+"""
+blastware_file.py — Blastware binary file codec for bidirectional interoperability.
+
+Reads and writes the proprietary Instantel/Blastware file formats:
+  Waveform events (.CE0W, .VM0H, .440, .7M0, etc.) (extension encoding UNKNOWN — see below)
+  .MLG                        — Monitor log (monitoring session history)
+
+All waveform formats share a common 22-byte file header prefix and identical
+internal binary structure (same type tag 00 12 03 00, same STRT record layout).
+Blastware identifies the file type by extension, not by a magic marker.
+
+EXTENSION ENCODING — V10.72 firmware FULLY CONFIRMED 2026-04-22:
+
+  Direct / manual download:   AB0    (3-char, no type character)
+  Call-home (ACH) download:   AB0W or AB0H  (4-char, W=waveform H=histogram)
+
+  AB = 2-char base-36 of (total_seconds % 1296), where
+  total_seconds = (event_local_time − 1985-01-01T00:00:00_local).
+  0 = always literal digit zero.
+  Verified against 3,248 call-home files from a 10-year production archive.
+
+  The 10-year archive contains only ACH files (all end in W or H).
+  Manual Blastware downloads produce 3-char AB0 extensions — same encoding
+  but without the trailing type character.
+
+  Old firmware (S338, 3-char extensions): encoding unknown / same as manual?
+  Micromate Series 4 uses a different scheme (literal datetime in filename).
+
+─── File structure overview ─────────────────────────────────────────────────────
+
+Waveform file structure (confirmed from example-events/4-3-26-multi/M529LIY6 (example event)):
+
+  [22B header] [21B STRT record] [body bytes] [26B footer]
+
+  Header (22 bytes):
+    10 00 01 80 00 00  — fixed prefix
+    49 6e 73 74 61 6e 74 65 6c 00  — b'Instantel\x00'
+    07 2c              — fixed
+    00 12 03 00        — waveform file type tag (shared by all waveform extensions)
+
+  STRT record (21 bytes, immediately follows header):
+    53 54 52 54  — b'STRT'
+    ff fe        — fixed (2 bytes)
+    [key4]       — 4-byte waveform event key
+    [key4]       — 4-byte waveform event key (repeated)
+    [zeros]      — 7 bytes padding
+    [rectime]    — uint8 record time in seconds
+
+  Body (variable — reconstructed from A5 frame data):
+    The body bytes are derived from the raw A5 frame wire content, specifically
+    from the DLE-decoded representation of each frame's contribution.  See the
+    _frame_body_bytes() helper for the exact algorithm.
+
+  Footer (26 bytes):
+    0e 08
+    [ts1: 8B big-endian timestamp]  — start timestamp
+    [ts2: 8B big-endian timestamp]  — stop timestamp
+    00 01 00 02 00 00
+    [crc: 2B]  — CRC (algorithm unconfirmed; written as 0x00 0x00 placeholder)
+
+  Timestamp format (big-endian, 8 bytes):
+    [day] [month] [year_HI] [year_LO] [0x00] [hour] [min] [sec]
+
+MLG (monitor log, confirmed from example-events/4-3-26-multi/BE11529.MLG):
+
+  [308B header] [N × 292B records]
+
+  Header (308 bytes):
+    Offset 0x00: 10 00 01 80 00 00 Instantel\x00 07 2c 22 01 0e a0  — fixed (16B)
+    Offset 0x10: ... (unknown structure, written as zeros + serial)
+    Offset 0x2A: serial number (8 bytes, null-padded ASCII, e.g. "BE11529")
+    ... zero-padded to 308 bytes total
+
+  Record (292 bytes each):
+    [2B CRC]  — unknown algorithm; written as 0x00 0x00
+    22 01 0e 80  — record marker
+    [ts1: 8B big-endian timestamp]  — start time
+    [ts2: 8B big-endian timestamp]  — stop time (zeros if no stop)
+    [4B flags]  — see MLG_FLAGS_* constants below
+    [10B serial]  — null-padded serial number ASCII
+    [text]  — for trigger records: [0x08][8B ts1_copy] then ASCII "Geo: X.XXX in/s"
+             for monitoring records: b'' (or minimal separator)
+    [zero-padded to 292 bytes]
+
+─── Critical implementation notes ──────────────────────────────────────────────
+
+Waveform body reconstruction algorithm (confirmed 2026-04-21 from verification against
+M529LIY6 (example event) using raw_s3_20260403_153508.bin capture):
+
+  The waveform body bytes come from the A5 frame content, stripped of DLE-framing
+  artifacts.  Each A5 frame contributes a different slice of its data section,
+  with DLE+{0x02,0x03,0x04} byte pairs stripped.
+
+  Skip amounts per frame index (offsets into frame.data):
+    A5[0] (probe):     data[strt_pos + 21 + 7]  (skip header + STRT record)
+                       strt_pos found by searching frame.data[7:] for b'STRT';
+                       the contribution starts at strt_pos + 21 within data[7:]
+                       which equals strt_pos + 21 + 7 within frame.data.
+    A5[1]:             data[13]   (skip 7-byte frame.data prefix + 6 header bytes)
+    A5[2..N]:          data[12]   (skip 7-byte frame.data prefix + 5 header bytes)
+    Terminator A5:     data[11]   (1 byte less than chunk frames; terminator inner header
+                                   is 4 bytes instead of 5 — confirmed 2026-04-21)
+
+  DLE strip rule (applied AFTER slicing):
+    Strip any 0x10 byte that is immediately followed by 0x02, 0x03, or 0x04.
+    This undoes the DLE-escape that S3FrameParser preserves as literal pairs.
+    Applied to frame.data[skip:] + bytes([frame.chk_byte]) together, then
+    conditionally exclude the trailing chk_byte from the output.
+
+  chk_byte absorption:
+    When frame.data[-1] == 0x10 AND frame.chk_byte ∈ {0x02, 0x03, 0x04},
+    the last byte of frame.data is the DLE prefix of a split DLE+chk pair.
+    Including chk_byte in the strip buffer allows the pair to be stripped as
+    a unit.  After stripping, the trailing chk_byte is ALWAYS removed — because
+    _strip_inner_frame_dles keeps the byte after the DLE (the chk_byte value),
+    and that value is the checksum, never payload.  This applies to all three
+    cases (chk ∈ {0x02, 0x03, 0x04}) identically.
+
+MLG CRC:
+  The algorithm that produces the 2-byte CRC at the start of each MLG record
+  is unknown.  All examined records use non-zero values that do not match
+  CRC-16/CCITT, CRC-16/IBM, CRC-32 (truncated), word sums, XOR variants, or
+  any of the 40+ polynomial/init combinations tested.  The writer emits 0x0000.
+  This produces files that Blastware may reject or display without the CRC check —
+  the exact impact on BW import is unknown (TODO: test).
+
+─── Public API ──────────────────────────────────────────────────────────────────
+
+  blastware_filename(event, serial)
+      Return the correct Blastware filename for an event (e.g. "M529LIY6.CE0W").
+      Full AB0T extension encoding confirmed 2026-04-22 against 3,248 archive files.
+      Extension matches what Blastware itself would generate for the same event.
+
+  write_blastware_file(event, a5_frames, path)
+      Create a Blastware waveform file from an Event and the full A5 frame list.
+      All waveform extensions share the same binary format — the extension is set
+      by blastware_filename() based on the event timestamp and type.
+
+  read_blastware_file(path) → Event
+      Parse a Blastware waveform file into an Event object with waveform data populated.
+      (Not yet implemented — placeholder raises NotImplementedError.)
+
+  write_mlg(entries, serial, path)
+      Create a .MLG file from a list of MonitorLogEntry objects.
+
+  read_mlg(path) → list[MonitorLogEntry]
+      Parse a .MLG file into MonitorLogEntry objects.
+      (Not yet implemented — placeholder raises NotImplementedError.)
+"""
+
+from __future__ import annotations
+
+import datetime
+import logging
+import struct
+from pathlib import Path
+from typing import Optional, Union
+
+from .framing import S3Frame
+from .models import Event, MonitorLogEntry, Timestamp
+
+log = logging.getLogger(__name__)
+
+# ── File header constants ─────────────────────────────────────────────────────
+
+# Common 16-byte prefix shared by waveform files and MLG (confirmed from binary inspection).
+_FILE_HEADER_PREFIX = bytes.fromhex("1000018000004973") + b"tantel\x00\x07\x2c"
+# = 10 00 01 80 00 00 49 73 74 61 6e 74 65 6c 00 07 2c  (17 bytes)
+# Confirmed breakdown: 10 00 01 80 00 00 = fixed; "Instantel\x00" = 10B; 07 2c = fixed
+
+# Simpler construction:
+_FILE_HEADER_PREFIX = b"\x10\x00\x01\x80\x00\x00Instantel\x00\x07\x2c"  # 17 bytes
+
+# Waveform file type tag (4 bytes after common prefix) — shared by ALL waveform extensions
+_WAVEFORM_TYPE_TAG = b"\x00\x12\x03\x00"   # confirmed from M529LIY6 (example event) — same tag for .CE0W, .VM0H, etc.
+
+# MLG type tag (4 bytes after common prefix)
+_MLG_TYPE_TAG = b"\x22\x01\x0e\xa0"   # confirmed from BE11529.MLG  offset 0x11..0x14
+
+# Total header sizes
+_WAVEFORM_HEADER_SIZE = 22    # 17 + 4 = 21... wait. Let me recalculate.
+# From binary: first 22 bytes = header, then STRT at byte 22.
+# 17-byte common prefix + 4-byte type tag = 21 bytes. But observed header is 22B.
+# Checking: 6 fixed + 10 "Instantel\x00" + 2 "07 2c" = 18B prefix, then 4B type tag = 22B.
+# Re-count: b"\x10\x00\x01\x80\x00\x00" = 6B + b"Instantel\x00" = 10B + b"\x07\x2c" = 2B = 18B prefix.
+_FILE_HEADER_PREFIX = b"\x10\x00\x01\x80\x00\x00Instantel\x00\x07\x2c"  # 18 bytes
+_WAVEFORM_HEADER_SIZE = 22    # 18 + 4 = 22 bytes ✅
+_MLG_HEADER_SIZE = 308   # confirmed from BE11529.MLG
+
+# MLG record marker (4 bytes after 2-byte CRC at start of each record)
+_MLG_RECORD_MARKER = b"\x22\x01\x0e\x80"
+_MLG_RECORD_SIZE   = 292   # bytes per record (confirmed from BE11529.MLG)
+
+# MLG record flags (4 bytes at record[22:26])
+# Confirmed from BE11529.MLG binary inspection:
+MLG_FLAGS_START_ONLY = b"\xff\xff\x00\x00"   # monitoring start with no stop
+MLG_FLAGS_TRIGGER    = b"\x01\x00\x02\x00"   # triggered event (has ts1 + ts2)
+MLG_FLAGS_INTERVAL   = b"\x02\x00\x00\x00"   # monitoring interval (has ts1 + ts2)
+
+
+# ── Timestamp helpers ─────────────────────────────────────────────────────────
+
+def _encode_ts_be(ts: Optional[datetime.datetime]) -> bytes:
+    """
+    Encode a datetime as an 8-byte big-endian Blastware timestamp.
+
+    Format (waveform file and MLG record timestamps):
+      [day][month][year_HI][year_LO][0x00][hour][min][sec]
+
+    Big-endian year confirmed from M529LIY6 (example event) footer:
+      footer bytes [2..9] = 01 04 07 ea 00 00 1c 08
+      → day=1 month=4 year=0x07ea=2026 hour=0 min=28 sec=8  ✅
+
+    Returns 8 zero bytes if ts is None.
+    """
+    if ts is None:
+        return bytes(8)
+    return bytes([
+        ts.day,
+        ts.month,
+        (ts.year >> 8) & 0xFF,
+        ts.year & 0xFF,
+        0x00,
+        ts.hour,
+        ts.minute,
+        ts.second,
+    ])
+
+
+def _decode_ts_be(raw: bytes) -> Optional[datetime.datetime]:
+    """
+    Decode an 8-byte big-endian Blastware timestamp.
+
+    Returns None if the bytes are all zero or structurally invalid.
+    """
+    if len(raw) < 8 or raw == bytes(8):
+        return None
+    day   = raw[0]
+    month = raw[1]
+    year  = (raw[2] << 8) | raw[3]
+    hour  = raw[5]
+    minute = raw[6]
+    sec   = raw[7]
+    try:
+        return datetime.datetime(year, month, day, hour, minute, sec)
+    except ValueError:
+        return None
+
+
+def _ts_from_model(ts: Optional[Timestamp]) -> Optional[datetime.datetime]:
+    """Convert a models.Timestamp to datetime.datetime, or None."""
+    if ts is None:
+        return None
+    try:
+        return datetime.datetime(ts.year, ts.month, ts.day, ts.hour, ts.minute, ts.second)
+    except (ValueError, TypeError):
+        return None
+
+
+# ── DLE strip helper ──────────────────────────────────────────────────────────
+
+def _strip_inner_frame_dles(data: bytes) -> bytes:
+    """
+    Strip DLE (0x10) framing markers from A5 inner-frame content.
+
+    The A5 (bulk waveform stream) response body contains DLE-encoded sub-frame
+    structure.  S3FrameParser preserves DLE+XX pairs as two literal bytes in
+    frame.data.  Only the DLE marker byte needs to be removed; the following
+    byte is actual payload content.
+
+    Rule: when 0x10 is immediately followed by {0x02, 0x03, 0x04}, strip the
+    0x10 (DLE marker) and keep the following byte as payload.
+
+    Lone 0x10 bytes not followed by {0x02, 0x03, 0x04} are kept as-is.
+
+    Confirmed correct by verifying reconstructed waveform body against M529LIY6 (example event):
+      - 0x10 0x02 in terminator → 0x02 kept ✓
+      - 0x10 0x04 in terminator (month byte) → 0x04 kept ✓
+    """
+    out = bytearray()
+    i = 0
+    while i < len(data):
+        b = data[i]
+        if b == 0x10 and i + 1 < len(data) and data[i + 1] in {0x02, 0x03, 0x04}:
+            # Strip the DLE marker; the next byte is payload and will be appended
+            # in the next loop iteration.
+            i += 1
+            continue
+        out.append(b)
+        i += 1
+    return bytes(out)
+
+
+def _frame_body_bytes(frame: S3Frame, skip: int) -> bytes:
+    """
+    Extract the waveform body contribution from one A5 S3Frame.
+
+    The contribution is frame.data[skip:] with inner-frame DLE pairs stripped
+    per _strip_inner_frame_dles().  The chk_byte is temporarily appended before
+    stripping to handle the split-pair edge case where a DLE at the end of
+    frame.data is paired with chk_byte.
+
+    Split-pair edge case (confirmed for A5[8] of M529LIY6 (example event), 2026-04-21):
+
+    S3FrameParser appends DLE+XX pairs as two literal bytes when XX ∉ {DLE, ETX}.
+    When the LAST occurrence of such a pair straddles the payload/checksum boundary
+    (i.e., DLE is the last byte of raw_payload and XX is the checksum), the parser
+    splits them:
+      - DLE ends up as the last byte of frame.data  (frame.data[-1] == 0x10)
+      - XX is stored as frame.chk_byte
+
+    To strip the pair correctly, we reunite the bytes before calling the strip
+    function.  Since chk_byte is the checksum (not payload data), it is excluded
+    from the final output regardless of whether it was part of a pair.
+
+    Post-strip chk_byte removal (ALL cases):
+      _strip_inner_frame_dles strips the 0x10 and KEEPS chk_byte in all cases.
+      Chk_byte is always the checksum (not payload), so always strip it off.
+
+    Args:
+        frame: S3Frame with frame.data and frame.chk_byte populated.
+        skip:  Number of leading bytes in frame.data to exclude (frame header).
+
+    Returns:
+        bytes — the waveform body contribution for this frame.
+    """
+    if skip >= len(frame.data):
+        return b""
+
+    relevant = frame.data[skip:]
+
+    # Detect split DLE+chk pair at the frame boundary.
+    has_split_pair = (
+        len(relevant) > 0
+        and relevant[-1] == 0x10
+        and frame.chk_byte in {0x02, 0x03, 0x04}
+    )
+
+    if has_split_pair:
+        # Reunite the split pair so the strip function sees both bytes together.
+        buf = relevant + bytes([frame.chk_byte])
+        stripped = _strip_inner_frame_dles(buf)
+        # _strip_inner_frame_dles strips the DLE (0x10) and KEEPS chk_byte.
+        # chk_byte is the received checksum — never payload — so remove it.
+        # This is correct for all values in {0x02, 0x03, 0x04}.
+        if stripped:
+            stripped = stripped[:-1]
+        return stripped
+    else:
+        return _strip_inner_frame_dles(relevant)
+
+
+# ── Filename helper ───────────────────────────────────────────────────────────
+
+_INSTANTEL_EPOCH = datetime.datetime(1985, 1, 1, 0, 0, 0)
+"""
+Instantel timestamp epoch — January 1, 1985, 00:00:00 local time.
+Confirmed 2026-04-21: stem values for 6 independent events (April 1–9, 2026)
+all converge to this epoch when decoded as floor(seconds_since_epoch / 1296).
+1985 is the year Instantel was founded.
+"""
+
+_STEM_UNIT_SEC = 1296  # = 36^2 seconds ≈ 21.6 minutes per stem unit
+
+_STEM_CHARS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+# ── Waveform file extension encoding ─────────────────────────────────────────
+#
+# NEW FIRMWARE (V10.72+) — FULLY DECODED (confirmed 2026-04-21, 10-year archive):
+#
+#   Extension format: AB0T  (4 characters)
+#     AB = 2-char base-36 encoding of (seconds_since_epoch % 1296)
+#          i.e. the number of seconds into the current 21.6-minute stem window
+#          Range: 0 ("00") to 1295 ("ZZ")
+#     0  = always literal '0'
+#     T  = event type:  'W' = Full Waveform,  'H' = Full Histogram
+#
+#   Combined with the 4-char stem (which encodes seconds_since_epoch // 1296),
+#   the FULL filename gives a second-resolution timestamp:
+#     total_seconds = stem_val * 1296 + ab_val
+#     timestamp = EPOCH + timedelta(seconds=total_seconds)
+#
+#   Verified against three S353L4H0 events (all three match to the second):
+#     S353L4H0.3M0W  Full Waveform   2025-06-23 13:57:22  AB=3M=130  ✓
+#     S353L4H0.8S0H  Full Histogram  2025-06-23 14:00:28  AB=8S=316  ✓
+#     S353L4H0.9X0W  Full Waveform   2025-06-23 14:01:09  AB=9X=357  ✓
+#
+# OLD FIRMWARE (S338, 3-char extensions ending in '0') — UNKNOWN:
+#   Observed (old firmware / manual downloads): .440, .470, .7M0, .9T0, .EI0, etc.
+#   The V10.72 formula does NOT apply to these.
+#   Extension is NOT recording mode (refuted 2026-04-21: continuous → .EI0, not .9T0).
+#   blastware_filename() computes the correct AB0 extension for V10.72 firmware.
+#
+# WRONG earlier assumption (do not re-introduce):
+#   Extension was believed to encode recording mode × sample rate.
+#   Refuted by continuous-mode event producing .EI0 instead of .9T0.
+
+
+def _make_stem(ts_local: datetime.datetime) -> str:
+    """
+    Encode a local timestamp as a 4-character uppercase base-36 stem.
+
+    Algorithm (confirmed 2026-04-21 from 6 known file/timestamp pairs):
+      stem_int = floor((ts_local - Jan_1_1985_midnight_local) / 1296_seconds)
+      stem = 4-char uppercase base-36 encoding of stem_int
+
+    Unit = 36² = 1296 seconds ≈ 21.6 minutes.  Events within the same 1296-second
+    window receive the same stem; their extension distinguishes them.
+    """
+    delta_sec = int((ts_local - _INSTANTEL_EPOCH).total_seconds())
+    n = delta_sec // _STEM_UNIT_SEC
+    s = ""
+    for _ in range(4):
+        s = _STEM_CHARS[n % 36] + s
+        n //= 36
+    return s
+
+
+def blastware_filename(event: Event, serial: str, ach: bool = False) -> str:
+    """
+    Return the correct Blastware filename for an event.
+
+    CONFIRMED 2026-04-22 — verified against 3,248 files from a 10-year archive.
+
+    Filename format: <prefix_letter><serial3><stem><AB>0[T]
+    where:
+
+      prefix_letter = chr(ord('B') + floor(serial_numeric / 1000))
+        — encodes the production generation (batch of 1000 units)
+        — e.g. BE6907→H, BE11529→M, BE14036→P, BE18003→T
+
+      serial3 = f"{serial_numeric % 1000:03d}"
+        — last 3 digits of numeric serial, zero-padded
+
+      stem = 4-char base-36 of floor(total_seconds / 1296)
+        — encodes which 21.6-minute window the event fell in
+
+      AB = 2-char base-36 of (total_seconds % 1296)
+        — encodes seconds within the window (0–1295)
+
+      0 = always literal digit zero
+
+      T = 'W' or 'H' — ONLY appended for call-home (ACH) downloads (ach=True).
+        Manual / direct downloads produce a 3-char extension (AB0) with no type char.
+        Call-home downloads produce a 4-char extension (AB0W or AB0H).
+
+      total_seconds = (event_local_time − 1985-01-01T00:00:00_local) in seconds
+
+    The 10-year production archive contains only call-home files (all end in W or H).
+    Manual Blastware downloads produce 3-char extensions — the same AB0 prefix but
+    without the trailing type character.
+
+    Micromate Series 4 uses a completely different naming scheme (literal datetime
+    in filename); this function does not apply to Micromate units.
+
+    Args:
+        event:  Event object with timestamp set.
+        serial: Device serial number string (e.g. "BE11529").
+        ach:    If True, append W/H type character (call-home style).
+                If False (default), omit type character (direct download style).
+
+    Returns:
+        Filename string, e.g. "M529LIY6.CE0" (direct) or "M529LIY6.CE0H" (ACH).
+    """
+    # ── Serial prefix ──────────────────────────────────────────────────────────
+    serial_digits = "".join(c for c in serial if c.isdigit())
+    if len(serial_digits) >= 1:
+        serial_numeric = int(serial_digits)
+        generation = serial_numeric // 1000
+        prefix_letter = chr(ord('B') + generation)
+        serial3 = f"{serial_numeric % 1000:03d}"
+    else:
+        prefix_letter = "M"   # fallback
+        serial3 = "000"
+    prefix = prefix_letter + serial3
+
+    # ── Stem + AB extension from timestamp ────────────────────────────────────
+    if event.timestamp is not None:
+        try:
+            ts_local = datetime.datetime(
+                event.timestamp.year, event.timestamp.month, event.timestamp.day,
+                event.timestamp.hour, event.timestamp.minute, event.timestamp.second,
+            )
+            delta_sec = int((ts_local - _INSTANTEL_EPOCH).total_seconds())
+            stem = _make_stem(ts_local)
+            ab_val = delta_sec % _STEM_UNIT_SEC
+            ab_str = _STEM_CHARS[ab_val // 36] + _STEM_CHARS[ab_val % 36]
+        except (ValueError, TypeError, AttributeError):
+            stem = "0000"
+            ab_str = "00"
+    else:
+        stem = "0000"
+        ab_str = "00"
+
+    # ── Type character (ACH only) ─────────────────────────────────────────────
+    if ach:
+        if getattr(event, 'recording_mode', None) in (3, 4):  # Histogram / Hist+Cont
+            type_char = 'H'
+        else:
+            type_char = 'W'
+        ext = f".{ab_str}0{type_char}"
+    else:
+        ext = f".{ab_str}0"
+
+    return prefix + stem + ext
+
+
+# ── A5 frame classifier ───────────────────────────────────────────────────────────
+
+# ASCII markers that identify a compliance-config / metadata frame.
+# These strings appear in the A5 bulk stream as part of the device's
+# compliance setup payload.  They should NEVER appear in raw ADC waveform
+# frames (which are binary-heavy, < 20 % printable ASCII).
+_METADATA_FRAME_MARKERS = (
+    b"Project:",
+    b"Client:",
+    b"Standard Recording Setup",
+    b"Extended Notes",
+    b"User Name:",
+    b"Seis Loc:",
+)
+
+
+def classify_frame(frame: S3Frame) -> str:
+    """
+    Classify an A5 bulk waveform stream frame by its content.
+
+    Returns one of:
+        "terminator"    — page_key == 0x0000
+        "probe_or_strt" — data contains b"STRT\xff\xfe" (the initial probe response)
+        "metadata"      — data contains ASCII compliance-config markers
+        "waveform"      — predominantly binary (< 20 % printable ASCII)
+        "unknown"       — none of the above criteria matched
+
+    Used by write_blastware_file() to filter non-waveform frames out of
+    the reconstructed body so that metadata blocks (Project:, Client:, …)
+    and spurious STRT records do not corrupt the output file.
+    """
+    if frame.page_key == 0x0000:
+        return "terminator"
+    data = bytes(frame.data)
+    if b"STRT\xff\xfe" in data:
+        return "probe_or_strt"
+    if any(m in data for m in _METADATA_FRAME_MARKERS):
+        return "metadata"
+    if len(data) > 0:
+        printable = sum(1 for b in data if 32 <= b < 127)
+        if printable / len(data) < 0.20:
+            return "waveform"
+    return "unknown"
+
+
+# ── Waveform file writer ───────────────────────────────────────────────────────────
+
+def write_blastware_file(
+    event: Event,
+    a5_frames: list[S3Frame],
+    path: Union[str, Path],
+) -> None:
+    """
+    Write a Blastware waveform file from a downloaded event.
+
+    Args:
+        event:     Event object (populated by get_events() or download_waveform()).
+                   Used for the STRT record (key, rectime) and footer timestamps.
+        a5_frames: Complete A5 frame list INCLUDING the terminator frame
+                   (page_key=0x0000).  Pass include_terminator=True to
+                   read_bulk_waveform_stream() when collecting frames.
+                   Must have at least 2 frames (probe + terminator).
+        path:      Destination file path.  Parent directory must exist.
+                   Extension should be set via blastware_filename().
+
+    File layout:
+        [22B header] [21B STRT] [body bytes] [26B footer]
+
+    Raises:
+        ValueError: if a5_frames is empty or has no terminator (page_key=0).
+        OSError: if the file cannot be written.
+
+    Confirmed correct waveform body reconstruction against M529LIY6 (example event) (2026-04-21).
+    """
+    if not a5_frames:
+        raise ValueError("a5_frames must not be empty")
+
+    path = Path(path)
+
+    # ── Extract STRT record from probe frame ────────────────────────────────
+    # The STRT record (21 bytes) lives verbatim inside A5[0].data[7:].
+    # It is stored as-is in the waveform file — do NOT reconstruct it from Event
+    # fields, as bytes [10:14] and [14:20] contain device-specific values
+    # (not simply key4 repeated or zero-padded).  Confirmed 2026-04-21.
+    #
+    # STRT layout (21 bytes, observed in M529LIY6 files):
+    #   [0:4]   b'STRT'
+    #   [4:6]   0xff 0xfe (fixed)
+    #   [6:10]  key4 (event key)
+    #   [10:14] device-specific field (NOT a key4 repeat)
+    #   [14:20] device-specific fields (NOT zeros)
+    #   [20]    rectime uint8 seconds
+    # Extract STRT from the DLE-stripped probe frame.
+    #
+    # frame.data[7:] is the raw wire representation; it may contain DLE+{02,03,04}
+    # inner-frame pairs that S3FrameParser preserves as two literal bytes.  The
+    # Blastware file stores the stripped form, so we must strip before extracting.
+    #
+    # Example (M529LK0Y, 2026-04-21): STRT contains value 0x02 encoded as [10 02]
+    # on the wire.  Without stripping, STRT is 22 raw bytes → write_blastware_file writes the
+    # DLE prefix into the file AND begins the body 1 byte too early (probe_skip off
+    # by 1).  Stripping fixes both.
+    #
+    # probe_skip must be computed in the RAW frame.data domain (it is used as the
+    # `skip` argument to _frame_body_bytes which operates on raw frame.data).
+    # We walk the raw bytes counting stripped bytes until we have passed
+    # strt_pos + 21 stripped bytes, giving the raw offset of the first body byte.
+    w0_raw = bytes(a5_frames[0].data[7:])
+    w0_stripped = _strip_inner_frame_dles(w0_raw)
+    strt_pos_stripped = w0_stripped.find(b"STRT")
+
+    if strt_pos_stripped >= 0:
+        strt = bytes(w0_stripped[strt_pos_stripped : strt_pos_stripped + 21])
+
+        # Walk raw bytes to find the raw-domain end of the STRT (= body start).
+        target_stripped = strt_pos_stripped + 21
+        stripped_so_far = 0
+        raw_i = 0
+        while stripped_so_far < target_stripped and raw_i < len(w0_raw):
+            if (w0_raw[raw_i] == 0x10
+                    and raw_i + 1 < len(w0_raw)
+                    and w0_raw[raw_i + 1] in {0x02, 0x03, 0x04}):
+                raw_i += 2   # DLE pair → 1 stripped byte, 2 raw bytes
+            else:
+                raw_i += 1   # normal byte → 1 stripped byte, 1 raw byte
+            stripped_so_far += 1
+        probe_skip = 7 + raw_i  # raw bytes to skip: 7 header + raw STRT length
+    else:
+        # Fallback: construct a minimal STRT if probe frame lacks it
+        key4 = event._waveform_key if hasattr(event, '_waveform_key') and event._waveform_key else bytes(4)
+        rectime = event.rectime_seconds if event.rectime_seconds is not None else 0
+        strt = b"STRT" + b"\xff\xfe" + key4 + bytes(14) + bytes([rectime & 0xFF])
+        probe_skip = 7 + 21
+
+    log.warning(
+        "write_blastware_file: strt_pos_stripped=%d  probe_skip=%d  "
+        "probe_data_len=%d  strt_hex=%s",
+        strt_pos_stripped if strt_pos_stripped >= 0 else -1,
+        probe_skip,
+        len(a5_frames[0].data),
+        strt.hex() if len(strt) >= 4 else "(short)",
+    )
+
+    if len(strt) != 21:
+        raise ValueError(f"STRT record must be 21 bytes, got {len(strt)}")
+
+    # ── Build waveform file header ─────────────────────────────────────────────────────
+    header = _FILE_HEADER_PREFIX + _WAVEFORM_TYPE_TAG
+    assert len(header) == _WAVEFORM_HEADER_SIZE, f"Waveform header must be {_WAVEFORM_HEADER_SIZE} bytes"
+
+    # ── Build body from A5 frames ────────────────────────────────────────────
+    # The waveform body is reconstructed from ALL A5 frames (data + terminator).
+    # The terminator frame's contribution includes the 26-byte footer at its end.
+    #
+    # Reconstruction layout (confirmed from M529LIY6 captures, 2026-04-21):
+    #   all_bytes = contributions from A5[0..N] + terminator_contribution
+    #   body      = all_bytes[:-26]   (everything except the last 26 bytes)
+    #   footer    = all_bytes[-26:]   (last 26 bytes = the waveform file footer)
+    #
+    # The footer bytes come directly from the terminator frame's inner content —
+    # using them verbatim ensures timestamps match the device's recorded values.
+
+    # Separate terminator from data frames.
+    # Search from the FRONT for the first terminator (page_key == 0x0000).
+    # Do NOT use a5_frames[-1] — if _a5_frames contains stray frames from a
+    # subsequent event (a known get_events side-effect), the last frame will
+    # not be the terminator and the footer will be mis-identified.
+    term_idx: Optional[int] = None
+    for _i, _f in enumerate(a5_frames):
+        if _f.page_key == 0x0000:
+            term_idx = _i
+            break
+
+    if term_idx is not None:
+        body_frames = a5_frames[:term_idx]
+        term_frame  = a5_frames[term_idx]
+    else:
+        body_frames = a5_frames
+        term_frame  = None
+
+    log.warning(
+        "write_blastware_file: %d body_frames  term_idx=%s",
+        len(body_frames),
+        str(term_idx) if term_idx is not None else "None",
+    )
+
+    all_bytes = bytearray()
+
+    for fi, frame in enumerate(body_frames):
+        # All body frames contribute to the waveform body — no frames are skipped.
+        #
+        # Over TCP via cellular modem, _recv_5a_batch() correctly collects all
+        # A5 frames per chunk request (the device's ~1100-byte RS-232 response
+        # is forwarded as ~2 TCP segments of ~550 bytes each, each parsed as a
+        # separate S3 frame).  ALL of these frames contain ADC body data and
+        # must be included in the file — confirmed from 4-27-26 TCP capture
+        # analysis: contributions from all 14 frames → 6821 bytes → file 6864 bytes.
+        #
+        # Skip amounts (offsets into frame.data):
+        #   fi=0 (probe): probe_skip — skips the type_tag header + STRT record
+        #   fi=1:         13         — 7-byte frame.data prefix + 6 inner header bytes
+        #   fi>=2:        12         — 7-byte frame.data prefix + 5 inner header bytes
+        if fi == 0:
+            skip = probe_skip
+        elif fi == 1:
+            skip = 13
+        else:
+            skip = 12
+
+        contribution = _frame_body_bytes(frame, skip)
+        log.warning("write_blastware_file: fi=%d skip=%d raw_data=%d contribution=%d",
+                    fi, skip, len(frame.data), len(contribution))
+        all_bytes.extend(contribution)
+
+    # Terminator contributes its content, which ends with the 26-byte footer.
+    # skip=11 (not 12) because the terminator's inner frame header is 4 bytes,
+    # one shorter than chunk frames' 5-byte inner header.  Confirmed 2026-04-21.
+    if term_frame is not None:
+        term_contribution = _frame_body_bytes(term_frame, 11)
+        log.warning(
+            "write_blastware_file: term_frame data_len=%d  skip=11  "
+            "contribution_len=%d  first8=%s",
+            len(term_frame.data),
+            len(term_contribution),
+            term_contribution[:8].hex() if len(term_contribution) >= 8 else term_contribution.hex(),
+        )
+        all_bytes.extend(term_contribution)
+
+    log.warning(
+        "write_blastware_file: all_bytes total=%d  last28=%s",
+        len(all_bytes),
+        bytes(all_bytes[-28:]).hex() if len(all_bytes) >= 28 else bytes(all_bytes).hex(),
+    )
+
+    if len(all_bytes) >= 26:
+        body   = bytes(all_bytes[:-26])
+        footer = bytes(all_bytes[-26:])
+    else:
+        # Fallback: no terminator or very short stream → build footer from event metadata
+        body = bytes(all_bytes)
+        start_dt = _ts_from_model(event.timestamp)
+        stop_dt: Optional[datetime.datetime] = None
+        if start_dt is not None and event.rectime_seconds:
+            stop_dt = start_dt + datetime.timedelta(seconds=event.rectime_seconds)
+        footer = (
+            b"\x0e\x08"
+            + _encode_ts_be(start_dt)
+            + _encode_ts_be(stop_dt)
+            + b"\x00\x01\x00\x02\x00\x00"
+            + b"\x00\x00"   # CRC placeholder
+        )
+
+    # ── Write file ───────────────────────────────────────────────────────────
+    with open(path, "wb") as f:
+        f.write(header)
+        f.write(strt)
+        f.write(body)
+        f.write(footer)
+
+
+def read_blastware_file(path: Union[str, Path]) -> Event:
+    """
+    Parse a Blastware waveform file into an Event object.
+
+    NOT YET IMPLEMENTED.
+
+    Args:
+        path: Path to the waveform file.
+
+    Returns:
+        Event object with waveform data populated.
+
+    Raises:
+        NotImplementedError: always (pending implementation).
+    """
+    raise NotImplementedError("read_blastware_file() is not yet implemented")
+
+
+# ── MLG file writer ───────────────────────────────────────────────────────────
+
+def _build_mlg_header(serial: str) -> bytes:
+    """
+    Build the 308-byte MLG file header.
+
+    Header structure (confirmed from BE11529.MLG binary inspection):
+      Offset 0x00: 10 00 01 80 00 00 Instantel\x00 07 2c 22 01 0e a0  (22B)
+      Offset 0x16: ... (16B unknown — observed as zeros in BE11529.MLG)
+      Offset 0x2A: serial number (8 bytes, null-padded ASCII)
+      ... rest zero-padded to 308 bytes
+
+    The serial string "BE11529" appears at offset 0x2A (42 decimal).
+    """
+    buf = bytearray(_MLG_HEADER_SIZE)
+
+    # Common prefix + MLG type tag
+    prefix = _FILE_HEADER_PREFIX + _MLG_TYPE_TAG  # 22 bytes
+    buf[0:len(prefix)] = prefix
+
+    # Serial number at offset 0x2A
+    serial_bytes = serial.encode("ascii", errors="replace")[:8]
+    serial_padded = serial_bytes.ljust(8, b"\x00")
+    buf[0x2A : 0x2A + 8] = serial_padded
+
+    return bytes(buf)
+
+
+def _build_mlg_record(
+    entry: MonitorLogEntry,
+    serial: str,
+) -> bytes:
+    """
+    Build one 292-byte MLG record from a MonitorLogEntry.
+
+    Record layout (confirmed from BE11529.MLG binary inspection):
+      [0:2]    CRC         — 2-byte CRC (algorithm unknown; written as 0x0000)
+      [2:6]    marker      — 22 01 0e 80
+      [6:14]   ts1         — 8B big-endian start timestamp
+      [14:22]  ts2         — 8B big-endian stop timestamp
+      [22:26]  flags       — 4B record flags (see MLG_FLAGS_* constants)
+      [26:36]  serial      — 10B null-padded serial number
+      [36:]    text        — for triggered events: [0x08][8B ts1_copy]["Geo: X.XXX in/s"]
+                             for monitoring intervals: b"" or minimal separator
+      [... zero-padded to 292 bytes]
+
+    Flags based on entry type:
+      - MonitorLogEntry with start_time only (no stop_time): MLG_FLAGS_START_ONLY
+      - MonitorLogEntry with both times and geo_threshold_ips set: MLG_FLAGS_TRIGGER
+      - MonitorLogEntry with both times (monitoring interval): MLG_FLAGS_INTERVAL
+
+    The triggered-event text block (flags = MLG_FLAGS_TRIGGER):
+      [0x08] [ts1: 8B] [ASCII "Geo: X.XXX in/s\x00"]
+    Confirmed from BE11529.MLG records at offset 0x0134 and 0x0258.
+    """
+    buf = bytearray(_MLG_RECORD_SIZE)
+
+    start_dt = (
+        datetime.datetime(
+            entry.start_time.year, entry.start_time.month, entry.start_time.day,
+            entry.start_time.hour, entry.start_time.minute, entry.start_time.second,
+        )
+        if entry.start_time else None
+    )
+    stop_dt = (
+        datetime.datetime(
+            entry.stop_time.year, entry.stop_time.month, entry.stop_time.day,
+            entry.stop_time.hour, entry.stop_time.minute, entry.stop_time.second,
+        )
+        if entry.stop_time else None
+    )
+
+    # [0:2] CRC placeholder
+    buf[0:2] = b"\x00\x00"
+
+    # [2:6] Record marker
+    buf[2:6] = _MLG_RECORD_MARKER
+
+    # [6:14] ts1
+    buf[6:14] = _encode_ts_be(start_dt)
+
+    # [14:22] ts2
+    buf[14:22] = _encode_ts_be(stop_dt)
+
+    # [22:26] flags
+    if stop_dt is None:
+        flags = MLG_FLAGS_START_ONLY
+    elif entry.geo_threshold_ips is not None:
+        flags = MLG_FLAGS_TRIGGER
+    else:
+        flags = MLG_FLAGS_INTERVAL
+    buf[22:26] = flags
+
+    # [26:36] serial (10B null-padded)
+    serial_bytes = serial.encode("ascii", errors="replace")[:10]
+    buf[26 : 26 + len(serial_bytes)] = serial_bytes
+
+    # [36:] text content
+    pos = 36
+    if flags == MLG_FLAGS_TRIGGER:
+        # Extra ts1 copy: [0x08][ts1: 8B]
+        buf[pos] = 0x08
+        pos += 1
+        buf[pos : pos + 8] = _encode_ts_be(start_dt)
+        pos += 8
+
+    if entry.geo_threshold_ips is not None:
+        geo_text = f"Geo: {entry.geo_threshold_ips:.3f} in/s\x00".encode("ascii")
+        buf[pos : pos + len(geo_text)] = geo_text
+        pos += len(geo_text)
+
+    return bytes(buf)
+
+
+def write_mlg(
+    entries: list[MonitorLogEntry],
+    serial: str,
+    path: Union[str, Path],
+) -> None:
+    """
+    Write a Blastware .MLG monitor log file.
+
+    Args:
+        entries: List of MonitorLogEntry objects (from get_monitor_log_entries()).
+                 Each entry produces one 292-byte record in the file.
+        serial:  Device serial number string (e.g. "BE11529").
+                 Written to the file header and each record.
+        path:    Destination file path.  Extension is not enforced — use ".MLG".
+
+    File layout:
+        [308B header] [N × 292B records]
+
+    Note: The 2-byte CRC at the start of each record is written as 0x0000.
+    The CRC algorithm is unknown (see module docstring).
+
+    Raises:
+        OSError: if the file cannot be written.
+    """
+    path = Path(path)
+    header = _build_mlg_header(serial)
+
+    with open(path, "wb") as f:
+        f.write(header)
+        for entry in entries:
+            record = _build_mlg_record(entry, serial)
+            f.write(record)
+
+
+def read_mlg(path: Union[str, Path]) -> list[MonitorLogEntry]:
+    """
+    Parse a Blastware .MLG file into a list of MonitorLogEntry objects.
+
+    NOT YET IMPLEMENTED.
+
+    Args:
+        path: Path to the .MLG file.
+
+    Returns:
+        List of MonitorLogEntry objects.
+
+    Raises:
+        NotImplementedError: always (pending implementation).
+    """
+    raise NotImplementedError("read_mlg() is not yet implemented")
@@ -35,6 +35,7 @@ from typing import Optional

 from .framing import S3Frame
 from .models import (
+    CallHomeConfig,
    ComplianceConfig,
    DeviceInfo,
    Event,
@@ -448,7 +449,7 @@ class MiniMateClient:
        proto.confirm_erase_all()
        log.info("delete_all_events: erase confirmed — device memory cleared")

-    def get_events(self, full_waveform: bool = False, debug: bool = False, stop_after_index: Optional[int] = None, skip_waveform_for_keys: Optional[set] = None) -> list[Event]:
+    def get_events(self, full_waveform: bool = False, debug: bool = False, stop_after_index: Optional[int] = None, skip_waveform_for_keys: Optional[set] = None, extra_chunks_after_metadata: int = 1) -> list[Event]:
        """
        Download all stored events from the device using the confirmed
        1E → 0A → 0C → 5A → 1F event-iterator protocol.
@@ -603,10 +604,12 @@ class MiniMateClient:
                            "get_events: 5A full waveform download for key=%s", cur_key.hex()
                        )
                        a5_frames = proto.read_bulk_waveform_stream(
-                            cur_key, stop_after_metadata=False, max_chunks=128
+                            cur_key, stop_after_metadata=False, max_chunks=128,
+                            include_terminator=True,
                        )
                        if a5_frames:
                            a5_ok = True
+                            ev._a5_frames = a5_frames   # store for write_blastware_file
                            _decode_a5_metadata_into(a5_frames, ev)
                            _decode_a5_waveform(a5_frames, ev)
                            log.info(
@@ -618,10 +621,14 @@ class MiniMateClient:
                            "get_events: 5A metadata-only download for key=%s", cur_key.hex()
                        )
                        a5_frames = proto.read_bulk_waveform_stream(
-                            cur_key, stop_after_metadata=True
+                            cur_key, stop_after_metadata=True,
+                            include_terminator=True,
+                            extra_chunks_after_metadata=extra_chunks_after_metadata,
+                            max_chunks=128,
                        )
                        if a5_frames:
                            a5_ok = True
+                            ev._a5_frames = a5_frames   # store for write_blastware_file
                            _decode_a5_metadata_into(a5_frames, ev)
                            log.debug(
                                "get_events: 5A metadata  client=%r  operator=%r",
@@ -775,6 +782,39 @@ class MiniMateClient:
        else:
            log.warning("download_waveform: waveform decode produced no samples")

+        return a5_frames
+
+    def save_blastware_file(self, event: "Event", path: "Union[str, Path]", serial: str) -> None:
+        """
+        Download the full waveform for *event* and save it as a Blastware-
+        compatible Blastware waveform file at *path*.
+
+        This is a convenience wrapper that calls download_waveform() (which
+        performs the complete SUB 5A BULK_WAVEFORM_STREAM download) and then
+        calls write_blastware_file() from blastware_file.py to encode the result.
+
+        Args:
+            event:  Event object with waveform key populated (from get_events()).
+            path:   Destination file path.  Caller should use blastware_filename()
+                    to pick the correct extension via blastware_filename().
+            serial: Device serial number (e.g. "BE11529") — passed to
+                    blastware_filename() for reference, but the caller supplies
+                    the final path.
+        """
+        from pathlib import Path as _Path
+        from .blastware_file import write_blastware_file as _write_blastware_file
+
+        a5_frames = self.download_waveform(event)
+        if not a5_frames:
+            raise RuntimeError(
+                f"save_blastware_file: no A5 frames received for event#{event.index}"
+            )
+        _write_blastware_file(event, a5_frames, path)
+        log.info(
+            "save_blastware_file: wrote %s (%d A5 frames)",
+            path, len(a5_frames),
+        )
+
    # ── Write commands ────────────────────────────────────────────────────────

    def push_config_raw(
@@ -894,14 +934,14 @@ class MiniMateClient:

        Write payloads:
          event_index_data : 88 bytes  — read live via SUB 08
-          compliance_data  : 2128 bytes — read live via SUB 1A (2126 bytes) + \\x00\\x00 footer
+          compliance_data  : ~2128 bytes — read live via SUB 1A (~2126 bytes, varies ±1-2) + \\x00\\x00 footer
          trigger_data     : 29 bytes  — hardcoded from 3-11-26 capture
          waveform_data    : 204 bytes — read live via SUB 09

        Raises:
            RuntimeError:  if not connected.
            ProtocolError: if any read or write step fails.
-            ValueError:    if compliance buffer is not the expected 2126 bytes.
+            ValueError:    if compliance buffer is shorter than the 2082-byte write minimum.
        """
        proto = self._require_proto()

@@ -910,7 +950,7 @@ class MiniMateClient:
        event_index_data = proto.read_event_index()

        log.info("apply_config: reading compliance config (SUB 1A)")
-        compliance_raw = proto.read_compliance_config()      # 2126 bytes
+        compliance_raw = proto.read_compliance_config()      # ~2126 bytes (varies ±1-2 by DLE jitter)

        log.info("apply_config: reading waveform data (SUB 09)")
        waveform_data = proto.read_waveform_data_raw()       # 204 bytes
@@ -956,6 +996,93 @@ class MiniMateClient:
            notes=notes,
        )

+    # ── Call home config ──────────────────────────────────────────────────────
+
+    def get_call_home_config(self) -> CallHomeConfig:
+        """
+        Read the auto call home (ACH) configuration from the device.
+
+        Sends SUB 0x2C (two-step read) and decodes the raw 125-byte payload
+        into a CallHomeConfig object.
+
+        Returns:
+            CallHomeConfig with all confirmed fields populated.
+
+        Raises:
+            RuntimeError:  if not connected.
+            ProtocolError: on timeout or wrong response SUB.
+        """
+        proto = self._require_proto()
+        raw = proto.read_call_home_config()
+        return _decode_call_home_config(raw)
+
+    def set_call_home_config(
+        self,
+        *,
+        auto_call_home_enabled: Optional[bool]  = None,
+        after_event_recorded:   Optional[bool]  = None,
+        at_specified_times:     Optional[bool]  = None,
+        time1_enabled:          Optional[bool]  = None,
+        time1_hour:             Optional[int]   = None,
+        time1_min:              Optional[int]   = None,
+        time2_enabled:          Optional[bool]  = None,
+        time2_hour:             Optional[int]   = None,
+        time2_min:              Optional[int]   = None,
+    ) -> None:
+        """
+        Read the current call home config, apply any supplied changes, and
+        write the updated config back to the device.
+
+        Only non-None arguments are modified.  All other bytes are round-tripped
+        verbatim from the device.
+
+        Configurable fields
+        -------------------
+        auto_call_home_enabled : bool  — master enable for ACH
+        after_event_recorded   : bool  — call home after each triggered event
+        at_specified_times     : bool  — call home at scheduled times
+        time1_enabled          : bool  — enable time slot 1
+        time1_hour             : int   — hour for time slot 1 (0-23)
+        time1_min              : int   — minute for time slot 1 (0-59)
+        time2_enabled          : bool  — enable time slot 2
+        time2_hour             : int   — hour for time slot 2 (0-23)
+        time2_min              : int   — minute for time slot 2 (0-59)
+
+        Write sequence (confirmed from 4-20-26 call home settings captures):
+          SUB 0x2C (read, 2-step) → 125-byte raw payload
+          patch fields in-place
+          SUB 0x7E (write, 127-byte payload) → ack 0x81
+          SUB 0x7F (confirm) → ack 0x80
+
+        Raises:
+            RuntimeError:  if not connected.
+            ProtocolError: if any read or write step fails.
+        """
+        proto = self._require_proto()
+
+        # 1. Read current config
+        log.info("set_call_home_config: reading current config (SUB 0x2C)")
+        raw = proto.read_call_home_config()
+
+        # 2. Patch fields and build write payload
+        write_data = _encode_call_home_config(
+            raw,
+            auto_call_home_enabled=auto_call_home_enabled,
+            after_event_recorded=after_event_recorded,
+            at_specified_times=at_specified_times,
+            time1_enabled=time1_enabled,
+            time1_hour=time1_hour,
+            time1_min=time1_min,
+            time2_enabled=time2_enabled,
+            time2_hour=time2_hour,
+            time2_min=time2_min,
+        )
+
+        # 3. Write back
+        log.info("set_call_home_config: writing updated config (SUB 0x7E + 0x7F)")
+        proto.write_call_home_config(write_data)
+        log.info("set_call_home_config: complete")
+
    def poll(self) -> None:
        """
        Perform just the POLL startup handshake — no config reads.
@@ -1236,7 +1363,7 @@ def _decode_waveform_record_into(data: bytes, event: Event) -> None:
        log.warning("waveform record project strings decode failed: %s", exc)


-def _decode_a5_metadata_into(frames_data: list[bytes], event: Event) -> None:
+def _decode_a5_metadata_into(frames_data: list[S3Frame], event: Event) -> None:
    """
    Search A5 (BULK_WAVEFORM_STREAM) frame data for event-time metadata strings
    and populate event.project_info.
@@ -1264,7 +1391,7 @@ def _decode_a5_metadata_into(frames_data: list[bytes], event: Event) -> None:

    Modifies event in-place.
    """
-    combined = b"".join(frames_data)
+    combined = b"".join(f.data for f in frames_data)

    def _find_string_after(needle: bytes, max_len: int = 64) -> Optional[str]:
        pos = combined.find(needle)
@@ -1288,7 +1415,7 @@ def _decode_a5_metadata_into(frames_data: list[bytes], event: Event) -> None:
    notes    = _find_string_after(b"Extended Notes")

    if not any([project, client, operator, location, notes]):
-        log.debug("a5 metadata: no project strings found in %d frames", len(frames_data))
+        log.debug("a5 metadata: no project strings found in %d frames (%d bytes)", len(frames_data), len(combined))
        return

    if event.project_info is None:
@@ -1314,7 +1441,7 @@ def _decode_a5_metadata_into(frames_data: list[bytes], event: Event) -> None:


 def _decode_a5_waveform(
-    frames_data: list[bytes],
+    frames_data: list[S3Frame],
    event: Event,
 ) -> None:
    """
@@ -1375,7 +1502,7 @@ def _decode_a5_waveform(
        return

    # ── Parse STRT record from A5[0] ────────────────────────────────────────
-    w0 = frames_data[0][7:]   # db[7:] for A5[0]
+    w0 = frames_data[0].data[7:]   # frame.data[7:] for A5[0]
    strt_pos = w0.find(b"STRT")
    if strt_pos < 0:
        log.warning("_decode_a5_waveform: STRT record not found in A5[0]")
@@ -1411,7 +1538,7 @@ def _decode_a5_waveform(
    global_offset = 0

    for fi, db in enumerate(frames_data):
-        w = db[7:]
+        w = db.data[7:]   # frame.data[7:]

        # A5[0]: waveform begins after the 21-byte STRT record and 6-byte preamble.
        # Layout: STRT(21B) + null-pad(2B) + 0xFF sentinel(4B) = 27 bytes total.
@@ -1682,10 +1809,13 @@ def _encode_compliance_config(
    DLE-jitter shifts):

      Anchor: b'\\xbe\\x80\\x00\\x00\\x00\\x00'  (confirmed stable, both BE11529 and BE18189)
-        recording_mode       → uint8 at anchor_pos - 7  (write payload)
+        recording_mode       → uint8 at anchor_pos - 8  (BOTH read and write)
                               Values: 0x00=Single Shot, 0x01=Continuous, 0x03=Histogram, 0x04=Histogram+Continuous
-                               NOTE: In the E5 read response (decode) field is at anchor_pos - 8 due to an
-                               extra 0x10 byte at read anchor_pos - 7.  Write payload has no extra byte.
+                               NOTE: The byte at anchor_pos - 7 is always 0x10 (a DLE marker regenerated by
+                               device firmware in every E5 response).  It must NOT be overwritten during
+                               write — doing so causes anchor drift (+1 per write cycle).
+                               CORRECTION 2026-04-21: previous doc stated anchor-7 for write; empirically
+                               confirmed wrong — writing to anchor-7 shifts the anchor by 1 on every cycle.
        sample_rate          → uint16 BE at anchor_pos - 6
        histogram_interval_sec → uint16 BE at anchor_pos - 4  (seconds; mode-gated to Histogram/Histogram+Continuous)
                               Valid values: 2, 5, 15, 60, 300, 900 (= 2s, 5s, 15s, 1m, 5m, 15m)
@@ -1718,10 +1848,26 @@ def _encode_compliance_config(
        by the device in POC test 2026-04-07.)

    Raises:
-        ValueError: if raw is not exactly 2126 bytes.
+        ValueError: if raw is shorter than the minimum needed for the 3-chunk write.
    """
-    if len(raw) != 2126:
-        raise ValueError(f"_encode_compliance_config: expected 2126 bytes, got {len(raw)}")
+    # Total size is nominally ~2126 bytes but varies by ±1-2 bytes depending on
+    # DLE jitter in the E5 read response (0x10 bytes in the config data cause
+    # 1-byte expansions per occurrence during DLE stuffing/unstuffing).  The
+    # anchor-based field access and the chunk splitter (fixed chunk1=1027,
+    # chunk2=1055, chunk3=remainder) both handle variable length correctly.
+    # Only enforce a minimum — must have at least chunk1+chunk2 bytes of content.
+    _MIN_COMPLIANCE_LEN = 1027 + 1055  # = 2082
+    if len(raw) < _MIN_COMPLIANCE_LEN:
+        raise ValueError(
+            f"_encode_compliance_config: compliance buffer too short "
+            f"({len(raw)} bytes, need at least {_MIN_COMPLIANCE_LEN})"
+        )
+    if len(raw) not in range(2124, 2132):
+        log.warning(
+            "_encode_compliance_config: unusual compliance buffer length %d "
+            "(expected ~2126); proceeding with anchor-based access",
+            len(raw),
+        )

    buf = bytearray(raw)

@@ -1729,13 +1875,40 @@ def _encode_compliance_config(
    _ANC = b'\xbe\x80\x00\x00\x00\x00'
    _anc = buf.find(_ANC, 0, 150)

+    # Log anchor position every time so we can detect unexpected shifts due to
+    # DLE jitter or firmware differences.  Expected position is ~15.
+    if _anc < 0:
+        log.warning(
+            "_encode_compliance_config: anchor NOT FOUND in cfg[0:150] "
+            "(buf len=%d) — all anchor-relative writes will be skipped",
+            len(buf),
+        )
+    else:
+        log.info(
+            "_encode_compliance_config: anchor at cfg[%d]  buf_len=%d  "
+            "(recording_mode@%d  DLE_marker@%d  sample_rate@%d:%d  "
+            "histogram_interval@%d:%d  record_time@%d:%d)",
+            _anc, len(buf),
+            _anc - 8,
+            _anc - 7,
+            _anc - 6, _anc - 4,
+            _anc - 4, _anc - 2,
+            _anc + 6, _anc + 10,
+        )
+
    if recording_mode is not None:
-        if _anc < 7:
+        if _anc < 8:
            log.warning("_encode_compliance_config: anchor not found — cannot write recording_mode")
        else:
-            buf[_anc - 7] = recording_mode & 0xFF
+            # Write to anchor-8, same physical position as the E5 read format.
+            # The byte at anchor-7 is a DLE marker (0x10) that the device firmware
+            # regenerates in every E5 response — it must NOT be overwritten.
+            # Writing to anchor-7 causes the device to add an extra byte on the
+            # next read-back, drifting the anchor by +1 on every write cycle.
+            # (CLAUDE.md "anchor-7 write" was incorrect — confirmed 2026-04-21)
+            buf[_anc - 8] = recording_mode & 0xFF
            log.debug("_encode_compliance_config: recording_mode=0x%02X -> offset %d",
-                      recording_mode, _anc - 7)
+                      recording_mode, _anc - 8)

    if sample_rate is not None:
        if _anc < 6:
@@ -1897,6 +2070,27 @@ def _decode_compliance_config_into(data: bytes, info: DeviceInfo) -> None:
    #   _anchor + 6 : record_time        (float32 BE)
    _ANCHOR = b'\xbe\x80\x00\x00\x00\x00'
    _anchor = data.find(_ANCHOR, 0, 150)
+
+    # Log anchor position on every decode so we can compare read vs write and
+    # catch unexpected shifts from DLE jitter or firmware differences.
+    # Expected position is ~15 for the E5 read payload (anchor - 8 = recording_mode).
+    if _anchor < 0:
+        log.warning(
+            "_decode_compliance_config_into: anchor NOT FOUND in data[0:150] (len=%d)",
+            len(data),
+        )
+    else:
+        log.info(
+            "_decode_compliance_config_into: anchor at data[%d]  data_len=%d  "
+            "(expected ~15; recording_mode@%d  sample_rate@%d:%d  "
+            "histogram_interval@%d:%d  record_time@%d:%d)",
+            _anchor, len(data),
+            _anchor - 8,
+            _anchor - 6, _anchor - 4,
+            _anchor - 4, _anchor - 2,
+            _anchor + 6, _anchor + 10,
+        )
+
    if _anchor >= 8 and _anchor + 10 <= len(data):
        try:
            config.recording_mode = data[_anchor - 8]
@@ -2232,3 +2426,160 @@ def _decode_monitor_status(data: bytes) -> MonitorStatus:
        memory_total=memory_total,
        memory_free=memory_free,
    )
+
+
+def _decode_call_home_config(raw: bytes) -> CallHomeConfig:
+    """
+    Decode the raw 125-byte call home config payload into a CallHomeConfig.
+
+    *raw* is data[11:] from the SUB 0xD3 data response frame.
+
+    Field offsets (confirmed from 4-20-26 captures, all 11 BW+S3 pairs):
+      [5]       auto_call_home_enabled  (0x00=off, 0x01=on)
+      [6:46]    dial_string             40-byte null-padded ASCII
+      [87]      after_event_recorded    (0x01=on, 0x00=off)
+      [91]      at_specified_times      (0x01=on, 0x00=off)
+      [93]      time1_enabled           (0x01=on, 0x00=off)
+      [95]      time2_enabled           (0x01=on, 0x00=off)
+      [101]     time1_hour              uint8 decimal 0-23
+      [102]     time1_min               uint8 decimal 0-59
+      [105]     time2_hour              uint8 decimal 0-23
+      [106]     time2_min               uint8 decimal 0-59
+      [117:119] 10 03 = DLE-escaped num_retries=3  (logical value = 0x03)
+      [120]     time_between_retries_sec   (shifted +1 from logical by DLE prefix)
+      [122]     wait_for_connection_sec
+      [124]     warm_up_time_sec
+
+    The DLE-escaped ETX at raw[117:119] = b'\\x10\\x03' means the logical value
+    0x03 (3 retries) is stored there.  The S3FrameParser keeps both bytes verbatim.
+    Subsequent fields are at logical_offset + 1 in the raw byte array.
+    """
+    cfg = CallHomeConfig(raw=raw)
+
+    if len(raw) < 10:
+        return cfg
+
+    # Simple boolean and string fields — direct reads, no DLE complications
+    if len(raw) > 5:
+        cfg.auto_call_home_enabled = bool(raw[5])
+    if len(raw) >= 46:
+        ds = raw[6:46]
+        cfg.dial_string = ds.split(b"\x00", 1)[0].decode("ascii", errors="replace") or None
+    if len(raw) > 87:
+        cfg.after_event_recorded = bool(raw[87])
+    if len(raw) > 91:
+        cfg.at_specified_times = bool(raw[91])
+    if len(raw) > 93:
+        cfg.time1_enabled = bool(raw[93])
+    if len(raw) > 95:
+        cfg.time2_enabled = bool(raw[95])
+    if len(raw) > 102:
+        cfg.time1_hour = raw[101]
+        cfg.time1_min  = raw[102]
+    if len(raw) > 106:
+        cfg.time2_hour = raw[105]
+        cfg.time2_min  = raw[106]
+
+    # num_retries: raw[117]=0x10 (DLE prefix), raw[118]=0x03 (value)
+    # Subsequent fields shift by +1 from logical positions.
+    if len(raw) > 118 and raw[117] == 0x10:
+        cfg.num_retries = raw[118]            # 0x03 = 3
+        if len(raw) > 120:
+            cfg.time_between_retries_sec = raw[120]   # logical 119, shifted to 120
+        if len(raw) > 122:
+            cfg.wait_for_connection_sec = raw[122]    # logical 121, shifted to 122
+        if len(raw) > 124:
+            cfg.warm_up_time_sec = raw[124]           # logical 123, shifted to 124
+    elif len(raw) > 117:
+        # Fallback: no DLE prefix (num_retries is not 0x03)
+        cfg.num_retries = raw[117]
+        if len(raw) > 119:
+            cfg.time_between_retries_sec = raw[119]
+        if len(raw) > 121:
+            cfg.wait_for_connection_sec = raw[121]
+        if len(raw) > 123:
+            cfg.warm_up_time_sec = raw[123]
+
+    log.debug(
+        "_decode_call_home_config: enabled=%s dial=%r after_event=%s at_times=%s "
+        "t1=%s %02d:%02d  t2=%s %02d:%02d  retries=%s gap=%s wait=%s warmup=%s",
+        cfg.auto_call_home_enabled, cfg.dial_string,
+        cfg.after_event_recorded, cfg.at_specified_times,
+        cfg.time1_enabled, cfg.time1_hour or 0, cfg.time1_min or 0,
+        cfg.time2_enabled, cfg.time2_hour or 0, cfg.time2_min or 0,
+        cfg.num_retries, cfg.time_between_retries_sec,
+        cfg.wait_for_connection_sec, cfg.warm_up_time_sec,
+    )
+    return cfg
+
+
+def _encode_call_home_config(
+    raw: bytes,
+    *,
+    auto_call_home_enabled: Optional[bool]  = None,
+    after_event_recorded:   Optional[bool]  = None,
+    at_specified_times:     Optional[bool]  = None,
+    time1_enabled:          Optional[bool]  = None,
+    time1_hour:             Optional[int]   = None,
+    time1_min:              Optional[int]   = None,
+    time2_enabled:          Optional[bool]  = None,
+    time2_hour:             Optional[int]   = None,
+    time2_min:              Optional[int]   = None,
+) -> bytes:
+    """
+    Patch specific fields in the 125-byte raw call home payload and return
+    the 127-byte write payload (raw + b'\\x00\\x00' footer).
+
+    Only non-None arguments are modified.  All other bytes including the
+    DLE-escaped \\x10\\x03 at [117:119] are preserved verbatim for round-trip.
+
+    The write payload footer (2 trailing zeros) matches Blastware's confirmed
+    write frame format from the 4-20-26 captures.
+
+    CAUTION: hour and minute values must not equal 0x03 (3) — such values would
+    require DLE-escaping that this encoder does not implement.  Values 0x03 in
+    hour/minute slots are rejected with ValueError.
+    """
+    if len(raw) < 107:
+        raise ValueError(
+            f"call home raw payload too short: {len(raw)} bytes (need ≥107)"
+        )
+    buf = bytearray(raw)   # 125 bytes
+
+    def _set_bool(offset: int, value: Optional[bool]) -> None:
+        if value is not None:
+            buf[offset] = 0x01 if value else 0x00
+
+    def _set_uint8(offset: int, value: Optional[int], name: str) -> None:
+        if value is None:
+            return
+        if value == 0x03:
+            raise ValueError(
+                f"{name}={value} (0x03) requires DLE escaping — "
+                "not supported by this encoder; avoid using 3 for hour/minute fields"
+            )
+        buf[offset] = value & 0xFF
+
+    _set_bool(5,   auto_call_home_enabled)
+    _set_bool(87,  after_event_recorded)
+    _set_bool(91,  at_specified_times)
+    _set_bool(93,  time1_enabled)
+    _set_bool(95,  time2_enabled)
+    _set_uint8(101, time1_hour, "time1_hour")
+    _set_uint8(102, time1_min,  "time1_min")
+    _set_uint8(105, time2_hour, "time2_hour")
+    _set_uint8(106, time2_min,  "time2_min")
+    # num_retries, time_between_retries_sec, wait_for_connection_sec, warm_up_time_sec
+    # are not writable via this encoder — they're preserved verbatim including the
+    # DLE-escaped 0x03 at [117:119].
+
+    log.debug(
+        "_encode_call_home_config: patched fields: "
+        "enabled=%s after_event=%s at_times=%s "
+        "t1=%s %s:%s  t2=%s %s:%s",
+        auto_call_home_enabled, after_event_recorded, at_specified_times,
+        time1_enabled, time1_hour, time1_min,
+        time2_enabled, time2_hour, time2_min,
+    )
+
+    return bytes(buf) + b"\x00\x00"  # append 2-byte footer (confirmed BW pattern)
@@ -457,6 +457,11 @@ class S3Frame:
    page_lo: int        # PAGE_LO from header
    data: bytes         # payload data section (payload[5:], checksum already stripped)
    checksum_valid: bool
+    chk_byte: int = 0   # actual checksum byte received from wire (body[-1])
+                        # needed for waveform file reconstruction: when the last data byte
+                        # is 0x10 and chk_byte ∈ {0x02, 0x03, 0x04}, the DLE+chk pair
+                        # must be included in the DLE-strip operation to correctly
+                        # reconstruct the Blastware binary body.

    @property
    def page_key(self) -> int:
@@ -597,4 +602,5 @@ class S3FrameParser:
            page_lo        = raw_payload[4],
            data           = raw_payload[5:],
            checksum_valid = (chk_received == chk_computed),
+            chk_byte       = chk_received,
        )
@@ -378,6 +378,78 @@ class ComplianceConfig:
    notes: Optional[str] = None            # extended notes / additional info


+# ── Call Home Config ──────────────────────────────────────────────────────────
+
+@dataclass
+class CallHomeConfig:
+    """
+    Auto Call Home (ACH) configuration from SUB 0x2C (response 0xD3).
+
+    Read with a standard two-step protocol (probe offset=0x00, data offset=0x7C).
+    Written via SUB 0x7E (write, 127-byte payload) + SUB 0x7F (confirm).
+
+    Confirmed from 4-20-26 call home settings captures (11 BW + S3 capture pairs).
+
+    Raw payload layout (data[11:] from S3 response, 125 bytes):
+      [0]     0x00           header byte
+      [1]     0x7C = 124     inner length (= offset for SUB 0x7E write - 2)
+      [2]     0xDC           constant
+      [3:5]   0x00 0x00      padding
+      [5]     auto_call_home_enabled  (0x00=off, 0x01=on) ✅
+      [6:46]  dial_string             40-byte null-padded ASCII ✅
+      [46:87] auto_answer_raw         AT command strings (not decoded) ✅ present
+      [87]    after_event_recorded    (0x01=on, 0x00=off) ✅
+      [91]    at_specified_times      (0x01=on, 0x00=off) ✅
+      [93]    time1_enabled           (0x01=on, 0x00=off) ✅
+      [95]    time2_enabled           (0x01=on, 0x00=off) ✅
+      [101]   time1_hour              uint8 decimal 0-23 ✅
+      [102]   time1_min               uint8 decimal 0-59 ✅
+      [105]   time2_hour              uint8 decimal 0-23 ✅
+      [106]   time2_min               uint8 decimal 0-59 ✅
+      [117]   DLE prefix (0x10)       ┐ DLE-escaped num_retries=3 (0x03)
+      [118]   0x03                    ┘ device stores/returns 0x03 DLE-escaped ✅
+      [120]   time_between_retries_sec uint8 (= 0x0F = 15 s default) ✅
+      [122]   wait_for_connection_sec  uint8 (= 0x3C = 60 s default) ✅
+      [124]   warm_up_time_sec         uint8 (= 0x3C = 60 s default) ✅
+
+    Write payload = raw 125 bytes + b'\\x00\\x00' (2 trailing zeros) = 127 bytes.
+    Offset for SUB 0x7E: data[1] + 2 = 0x7C + 2 = 0x7E = 126.
+
+    Note on DLE-escaped 0x03:  The device's S3 response DLE-escapes ETX (0x03)
+    bytes as \\x10\\x03.  The S3FrameParser preserves both bytes in frame.data.
+    Subsequent fields after offset 117 are therefore at raw_offset = logical+1.
+    The raw payload must be round-tripped verbatim in write; do NOT reapply DLE
+    destuffing or stripping.
+    """
+    raw: Optional[bytes] = None          # raw 125-byte read payload (for round-trip write)
+
+    # ── Main enable ──────────────────────────────────────────────────────────
+    auto_call_home_enabled: Optional[bool] = None    # raw[5] ✅
+
+    # ── Dial string ──────────────────────────────────────────────────────────
+    dial_string: Optional[str] = None                # raw[6:46] 40-byte null-padded ASCII ✅
+
+    # ── When to call ─────────────────────────────────────────────────────────
+    after_event_recorded: Optional[bool] = None      # raw[87] ✅
+    at_specified_times: Optional[bool] = None        # raw[91] ✅
+
+    # ── Time slot 1 ──────────────────────────────────────────────────────────
+    time1_enabled: Optional[bool] = None             # raw[93] ✅
+    time1_hour: Optional[int] = None                 # raw[101]  0-23 ✅
+    time1_min: Optional[int] = None                  # raw[102]  0-59 ✅
+
+    # ── Time slot 2 ──────────────────────────────────────────────────────────
+    time2_enabled: Optional[bool] = None             # raw[95] ✅
+    time2_hour: Optional[int] = None                 # raw[105]  0-23 ✅
+    time2_min: Optional[int] = None                  # raw[106]  0-59 ✅
+
+    # ── Retry / timeout settings (read-only; not writable via set_call_home_config) ──
+    num_retries: Optional[int] = None                # raw[117:119]=10 03 → value 3 ✅
+    time_between_retries_sec: Optional[int] = None   # raw[120] (shifted +1 by DLE) ✅
+    wait_for_connection_sec: Optional[int] = None    # raw[122] ✅
+    warm_up_time_sec: Optional[int] = None           # raw[124] ✅
+
+
 # ── Event ─────────────────────────────────────────────────────────────────────

@dataclass
@@ -421,6 +493,10 @@ class Event:
    # Set by get_events(); required by download_waveform().
    _waveform_key: Optional[bytes] = field(default=None, repr=False)

+    # Raw A5 frames from the full bulk waveform download (full_waveform=True).
+    # Populated by get_events() when full_waveform=True; used by write_blastware_file().
+    _a5_frames: Optional[list] = field(default=None, repr=False)
+
    def __str__(self) -> str:
        ts = str(self.timestamp) if self.timestamp else "no timestamp"
        ppv = ""
@@ -65,6 +65,7 @@ SUB_WAVEFORM_HEADER  = 0x0A
 SUB_WAVEFORM_RECORD  = 0x0C
 SUB_BULK_WAVEFORM    = 0x5A
 SUB_COMPLIANCE       = 0x1A
+SUB_CALL_HOME        = 0x2C   # Call home config read  → response 0xD3 ✅
 SUB_UNKNOWN_2E       = 0x2E

 # Write command SUBs (= Read SUB + 0x60, confirmed from BW captures 3-11-26)
@@ -78,6 +79,10 @@ SUB_WRITE_CONFIRM_C      = 0x74   # Confirm C — sent after 69 ✅
 SUB_TRIGGER_CONFIG_WRITE = 0x82   # Write trigger config (0x22 + 0x60) ✅
 SUB_TRIGGER_CONFIRM      = 0x83   # Confirm trigger write ✅

+# Call home write SUBs (confirmed from 4-20-26 call home settings captures)
+SUB_CALL_HOME_WRITE      = 0x7E   # Write call home config  → response 0x81 ✅
+SUB_CALL_HOME_CONFIRM    = 0x7F   # Confirm call home write → response 0x80 ✅
+
 # Monitoring control SUBs (confirmed from 4-8-26/2ndtry BW TX capture)
 SUB_START_MONITORING     = 0x96   # Start monitoring  → response 0x69 ✅
 SUB_STOP_MONITORING      = 0x97   # Stop monitoring   → response 0x68 ✅
@@ -109,6 +114,7 @@ DATA_LENGTHS: dict[int, int] = {
    # SUB_WAVEFORM_HEADER (0x0A) is VARIABLE — length read from probe response
    # data[4].  Do NOT add it here; use read_waveform_header() instead. ✅
    SUB_WAVEFORM_RECORD: 0xD2,  # 210-byte waveform/histogram record ✅
+    SUB_CALL_HOME:      0x7C,   # 124-byte call home config ✅ (confirmed 4-20-26)
    SUB_UNKNOWN_2E:     0x1A,   # 26 bytes, purpose TBD 🔶
    0x09:               0xCA,   # 202 bytes, purpose TBD 🔶
    # SUB_COMPLIANCE (0x1A) uses a multi-step sequence with a 2090-byte total;
@@ -120,10 +126,12 @@ DATA_LENGTHS: dict[int, int] = {
 _BULK_CHUNK_OFFSET = 0x1004   # offset field for probe + all regular chunk requests ✅
 _BULK_TERM_OFFSET  = 0x005A   # offset field for termination request ✅
 _BULK_COUNTER_STEP = 0x0400   # chunk counter increment per chunk ✅
-# Chunk counter formula: chunk_num * 0x0400 for ALL chunks including chunk 1.
-# Earlier captures showed 0x1004 for chunk 1 — that was a Blastware artifact, not a
-# protocol requirement.  Confirmed 2026-04-06: 0x0400 for chunk 1 works; 0x1004
-# causes a 120-second device timeout.  Formula n * 0x0400 is used for all chunks.
+# Chunk counter formula: key4[2:4] + (chunk_num - 1) * 0x0400
+# where key4[2:4] is the event's circular-buffer base offset ((key4[2]<<8)|key4[3]).
+# Earlier captures showed 0x1004 for chunk 1 of key 01110000 — that was a Blastware
+# artifact.  For keys where key4[2:4] != 0x0000 (e.g. key 01111884) the old
+# "n * 0x0400" formula sends counters from the wrong buffer region and the device
+# returns data from a different event.  Confirmed correct 2026-04-24.

 # Default timeout values (seconds).
 # MiniMate Plus is a slow device — keep these generous.
@@ -520,7 +528,9 @@ class MiniMateProtocol:
        *,
        stop_after_metadata: bool = True,
        max_chunks: int = 32,
-    ) -> list[bytes]:
+        include_terminator: bool = False,
+        extra_chunks_after_metadata: int = 1,
+    ) -> list[S3Frame]:
        """
        Download the SUB 5A (BULK_WAVEFORM_STREAM) A5 frames for one event.

@@ -536,7 +546,9 @@ class MiniMateProtocol:
          4. Termination (offset=_BULK_TERM_OFFSET, counter=last+_BULK_COUNTER_STEP)
             Device responds with a final A5 frame (page_key=0x0000).

-        The termination frame (page_key=0x0000) is NOT included in the returned list.
+        By default the termination frame (page_key=0x0000) is NOT included in the
+        returned list.  Pass include_terminator=True to append it; the blastware_file
+        writer needs the terminator frame's body to reconstruct the waveform file footer.

        Args:
            key4:                4-byte waveform key from EVENT_HEADER (1E).
@@ -546,11 +558,16 @@ class MiniMateProtocol:
                                 hundred KB).  Set False to download everything.
            max_chunks:          Safety cap on the number of chunk requests sent
                                 (default 32; a typical event uses 9 large frames).
+            include_terminator:  If True, append the terminator A5 frame
+                                 (page_key=0x0000) to the returned list.  The
+                                 terminator carries the waveform file footer bytes.
+                                 Default False preserves existing caller behaviour.

        Returns:
-            List of raw data bytes from each A5 response frame (not including
-            the terminator frame).  Frame indices match the request sequence:
-            index 0 = probe response, index 1 = first chunk, etc.
+            List of S3Frame objects from each A5 response frame.  Frame indices
+            match the request sequence: index 0 = probe response, index 1 = first
+            chunk, etc.  If include_terminator=True, the last element is the
+            terminator frame (page_key=0x0000).

        Raises:
            ProtocolError: on timeout, bad checksum, or unexpected SUB.
@@ -565,16 +582,24 @@ class MiniMateProtocol:
            raise ValueError(f"waveform key must be 4 bytes, got {len(key4)}")

        rsp_sub = _expected_rsp_sub(SUB_BULK_WAVEFORM)   # 0xFF - 0x5A = 0xA5
-        frames_data: list[bytes] = []
+        frames_data: list[S3Frame] = []
        counter = 0

+        # BW counter formula (confirmed from 4-3-26 capture for key 0111245a,
+        # and empirical live-device test 2026-04-06 for key 01110000):
+        #   counter for chunk n = max(key4[2:4], 0x0400) + (n - 1) * 0x0400
+        # key4[2:4] is the event's circular-buffer base offset.  The max() guard
+        # ensures chunk 1 never uses counter=0x0000 (which equals the probe address
+        # and causes the device to re-return STRT record data for the first chunk).
+        _key4_offset = (key4[2] << 8) | key4[3]
+
        # ── Step 1: probe ────────────────────────────────────────────────────
-        log.debug("5A probe  key=%s", key4.hex())
+        log.debug("5A probe  key=%s  key4_offset=0x%04X", key4.hex(), _key4_offset)
        params = bulk_waveform_params(key4, 0, is_probe=True)
        self._send(build_5a_frame(_BULK_CHUNK_OFFSET, params))
        self._parser.reset()        # reset bytes_fed counter before probe recv
        try:
-            rsp = self._recv_one(expected_sub=rsp_sub, reset_parser=False)
+            probe_batch = self._recv_5a_batch(rsp_sub)
        except TimeoutError:
            log.warning(
                "5A probe TIMED OUT for key=%s — "
@@ -582,23 +607,54 @@ class MiniMateProtocol:
                key4.hex(), self._parser.bytes_fed,
            )
            raise
-        frames_data.append(rsp.data)
-        log.debug("5A A5[0]  page_key=0x%04X  %d bytes", rsp.page_key, len(rsp.data))
+        frames_data.extend(probe_batch)
+        log.debug(
+            "5A probe: %d frame(s)  page_keys=%s",
+            len(probe_batch),
+            [f"0x{f.page_key:04X}" for f in probe_batch],
+        )
+
+        # Log probe frame size for diagnostics.
+        # The device always needs extra_chunks_after_metadata chunks after the
+        # metadata frame before termination to prime the valid waveform footer.
+        # This holds regardless of TCP frame size (1-frame vs 2-frame mode).
+        _effective_extra_chunks = extra_chunks_after_metadata
+        log.warning(
+            "5A probe data_len=%d  effective_extra_chunks=%d",
+            len(probe_batch[0].data),
+            _effective_extra_chunks,
+        )

        # ── Step 2: chunk loop ───────────────────────────────────────────────
-        # Chunk counters are monotonic: chunk_num * 0x0400 for all chunks.
-        # The 4-2-26 BW TX capture showed 0x1004 for chunk 1, but this is a
-        # Blastware artifact — the device accepts any counter value and streams
-        # data regardless.  Empirically confirmed 2026-04-06: 0x0400 for chunk 1
-        # works; 0x1004 causes the device to ignore the frame (timeout).
+        # Counter formula: _chunk_base + (chunk_num - 1) * 0x0400
+        # where _chunk_base = max(key4[2:4], 0x0400).
+        #
+        # For events with key4[2:4] != 0 (e.g. key 0111245a, offset 0x245a):
+        #   _chunk_base = 0x245a  →  chunk 1=0x245a, chunk 2=0x285a, ...
+        #   Confirmed from 4-3-26 capture.
+        #
+        # For events with key4[2:4] == 0 (e.g. key 01110000):
+        #   _chunk_base = max(0, 0x0400) = 0x0400
+        #   →  chunk 1=0x0400, chunk 2=0x0800, ... (= old chunk_num*0x0400)
+        #   CRITICAL: counter=0x0000 (same as the probe) causes the device to
+        #   re-return the STRT record data for chunk 1, making frame 1 look like
+        #   a second probe response (confirmed from server log: frame 1 len=1097,
+        #   contains STRT\xff\xfe, contributes zero body bytes after DLE-strip).
+        #   counter=0x0400 for chunk 1 confirmed working (empirical test 2026-04-06).
+        _chunk_base = max(_key4_offset, _BULK_COUNTER_STEP)
        for chunk_num in range(1, max_chunks + 1):
-            counter = chunk_num * _BULK_COUNTER_STEP
+            counter = _chunk_base + (chunk_num - 1) * _BULK_COUNTER_STEP
            params  = bulk_waveform_params(key4, counter)
            log.debug("5A chunk %d  counter=0x%04X", chunk_num, counter)
            self._send(build_5a_frame(_BULK_CHUNK_OFFSET, params))
            self._parser.reset()        # reset bytes_fed for accurate per-chunk count
            try:
-                rsp = self._recv_one(expected_sub=rsp_sub, reset_parser=False, timeout=10.0)
+                # Collect ALL frames from this chunk response.
+                # Over TCP via modem, a single large A5 device response (~1100 bytes
+                # RS-232) is split across ~2 TCP segments, each parsed as its own
+                # complete S3 frame.  _recv_5a_batch gathers all of them so that
+                # every subsequent chunk request is paired with the correct response.
+                batch = self._recv_5a_batch(rsp_sub, first_timeout=10.0)
            except TimeoutError:
                raw = self._parser.bytes_fed
                log.warning(
@@ -617,20 +673,51 @@ class MiniMateProtocol:
                    break
                raise

+            # Process all frames from this batch.
+            metadata_found = False
+            for rsp in batch:
                log.warning(
                    "5A RX chunk=%d page_key=0x%04X data_len=%d contains_Project=%s",
                    chunk_num, rsp.page_key, len(rsp.data), b"Project:" in rsp.data,
                )
-
                if rsp.page_key == 0x0000:
-                # Device unexpectedly terminated mid-stream (no termination needed).
-                log.debug("5A A5[%d] page_key=0x0000 — device terminated early", chunk_num)
+                    # Device unexpectedly terminated mid-stream.
+                    log.debug("5A page_key=0x0000 — device terminated early")
+                    if include_terminator:
+                        frames_data.append(rsp)
                    return frames_data
-
-            frames_data.append(rsp.data)
-
+                frames_data.append(rsp)
                if stop_after_metadata and b"Project:" in rsp.data:
-                log.debug("5A A5[%d] metadata found — stopping early", chunk_num)
+                    metadata_found = True
+
+            if metadata_found:
+                # Download extra_chunks_after_metadata more chunks after metadata.
+                # This primes the device to return the valid waveform footer in the
+                # termination response — without it the terminator carries too few bytes
+                # (confirmed 2026-04-23).  The extra chunk data also belongs in the
+                # file body (confirmed from TCP capture analysis 2026-04-27).
+                log.debug("5A metadata found — fetching %d more chunk(s)",
+                          _effective_extra_chunks)
+                for _extra_n in range(_effective_extra_chunks):
+                    chunk_num += 1
+                    counter = _chunk_base + (chunk_num - 1) * _BULK_COUNTER_STEP
+                    params = bulk_waveform_params(key4, counter)
+                    self._send(build_5a_frame(_BULK_CHUNK_OFFSET, params))
+                    try:
+                        extra_batch = self._recv_5a_batch(rsp_sub, first_timeout=10.0)
+                        for ef in extra_batch:
+                            log.debug(
+                                "5A extra chunk page_key=0x%04X data_len=%d",
+                                ef.page_key, len(ef.data),
+                            )
+                            if ef.page_key == 0x0000:
+                                if include_terminator:
+                                    frames_data.append(ef)
+                                return frames_data
+                            frames_data.append(ef)
+                    except TimeoutError:
+                        log.debug("5A extra chunk %d timed out — end of stream", _extra_n + 1)
+                        break
                break
        else:
            log.warning(
@@ -652,6 +739,8 @@ class MiniMateProtocol:
                "5A termination response  page_key=0x%04X  %d bytes",
                term_rsp.page_key, len(term_rsp.data),
            )
+            if include_terminator:
+                frames_data.append(term_rsp)
        except TimeoutError:
            log.debug("5A no termination response — device may have already closed")

@@ -1087,6 +1176,89 @@ class MiniMateProtocol:
        self._send(frame)
        return self.recv_write_ack(expected_sub=rsp_sub)

+    # ── Call home config (SUBs 0x2C / 0x7E / 0x7F) ──────────────────────────
+
+    def read_call_home_config(self) -> bytes:
+        """
+        Read the auto call home configuration (SUB 0x2C → response 0xD3).
+
+        Standard two-step read: probe (offset=0x00) then data (offset=0x7C=124).
+        Returns the raw 125-byte payload (data[11:] of the data response).
+
+        Confirmed from 4-20-26 call home settings capture:
+          - Probe response: data[4]=0x7C (confirms data length = 124)
+          - Data response: 136 bytes total (11-byte echo header + 125 bytes payload)
+          - Payload[0:3] = 0x00 0x7C 0xDC (header: zero, inner-length, constant)
+          - Payload[5]  = auto_call_home_enabled
+          - Payload[6:46] = dial_string (40-byte null-padded ASCII "RADIO RING")
+
+        Returns:
+            Raw 125-byte call home config payload (data[11:]).
+            Suitable for round-trip write (append \\x00\\x00 → 127-byte write payload).
+
+        Raises:
+            ProtocolError: on timeout or wrong response SUB.
+        """
+        rsp_sub = _expected_rsp_sub(SUB_CALL_HOME)   # 0xFF - 0x2C = 0xD3
+        length  = DATA_LENGTHS[SUB_CALL_HOME]         # 0x7C = 124
+
+        log.debug("read_call_home_config: 0x2C probe")
+        self._send(build_bw_frame(SUB_CALL_HOME, 0))
+        self._recv_one(expected_sub=rsp_sub)
+
+        log.debug("read_call_home_config: 0x2C data request offset=0x%02X", length)
+        self._send(build_bw_frame(SUB_CALL_HOME, length))
+        data_rsp = self._recv_one(expected_sub=rsp_sub)
+
+        payload = data_rsp.data[11:]
+        log.debug("read_call_home_config: received %d payload bytes", len(payload))
+        return payload
+
+    def write_call_home_config(self, data: bytes) -> None:
+        """
+        Write the auto call home configuration (SUB 0x7E → 0x7F confirm).
+
+        Write sequence (confirmed from 4-20-26 call home settings captures):
+          SUB 0x7E  write 127-byte payload  → device acks SUB 0x81
+          SUB 0x7F  confirm (no data)       → device acks SUB 0x80
+
+        The 127-byte write payload = 125-byte read payload + b'\\x00\\x00'.
+        The offset field = data[1] + 2 = 0x7C + 2 = 0x7E = 126.
+
+        Write frame format: build_bw_write_frame (minimal DLE stuffing — only
+        BW_CMD is doubled; all other bytes are RAW).  The \\x10\\x03 sequence
+        within the payload is preserved as-is (device interprets DLE+ETX as the
+        literal value 0x03 per the inner-frame terminator convention).
+
+        Args:
+            data: 127-byte write payload (read payload + \\x00\\x00 footer).
+                  Must start with [0x00][0x7C][...] (standard header).
+
+        Raises:
+            ValueError:    if data is not exactly 127 bytes or lacks expected header.
+            ProtocolError: on timeout or wrong response SUB.
+        """
+        if len(data) < 2:
+            raise ValueError(f"call home write payload must be at least 2 bytes, got {len(data)}")
+        rsp_sub_write   = _expected_rsp_sub(SUB_CALL_HOME_WRITE)    # 0xFF - 0x7E = 0x81
+        rsp_sub_confirm = _expected_rsp_sub(SUB_CALL_HOME_CONFIRM)  # 0xFF - 0x7F = 0x80
+
+        # Offset formula: data[1] + 2 (same pattern as other single-chunk writes)
+        offset = data[1] + 2   # 0x7C + 2 = 0x7E = 126
+        frame = build_bw_write_frame(SUB_CALL_HOME_WRITE, data, offset=offset)
+        log.debug(
+            "write_call_home_config: %d bytes  data[1]=0x%02X  offset=0x%04X",
+            len(data), data[1], offset,
+        )
+        self._send(frame)
+        self.recv_write_ack(expected_sub=rsp_sub_write)
+        log.debug("write_call_home_config: write acked; sending confirm 0x7F")
+
+        confirm_frame = build_bw_write_frame(SUB_CALL_HOME_CONFIRM, b"")
+        self._send(confirm_frame)
+        self.recv_write_ack(expected_sub=rsp_sub_confirm)
+        log.debug("write_call_home_config: confirm acked — done")
+
    # ── Monitoring ────────────────────────────────────────────────────────────

    def read_monitor_status(self) -> S3Frame:
@@ -1231,6 +1403,63 @@ class MiniMateProtocol:
        log.debug("TX %d bytes: %s", len(frame), frame.hex())
        self._transport.write(frame)

+    def _recv_5a_batch(
+        self,
+        expected_sub: int,
+        first_timeout: float = 10.0,
+        batch_timeout: float = 0.5,
+    ) -> list[S3Frame]:
+        """
+        Collect all S3 frames that arrive as part of one device response.
+
+        Over TCP via cellular modem, a single device A5 response (~1100 bytes of
+        RS-232 data) is forwarded in multiple TCP segments due to the modem's
+        data-forwarding timeout (~100-150 ms per segment).  Each TCP segment
+        contains a complete, valid S3 frame (~550 bytes).  Calling _recv_one()
+        once returns only the first segment's frame and misses the rest, causing
+        the chunk request/response pairing to cascade out of alignment.
+
+        This helper collects ALL frames before returning, by trying additional
+        short-timeout receives after the first frame arrives.
+
+        The caller must call self._parser.reset() before this method to ensure
+        bytes_fed is accurate; this method always uses reset_parser=False.
+
+        Args:
+            expected_sub:   Expected SUB byte for validation.
+            first_timeout:  Timeout for the mandatory first frame.  Should be
+                            generous (default 10 s) since the device may be slow.
+            batch_timeout:  Short timeout for subsequent frames.  Default 0.5 s
+                            — comfortably longer than the modem forwarding gap
+                            (~150 ms) but short enough to avoid stalling when
+                            only one frame is expected (probe, terminator).
+
+        Returns:
+            List of S3Frame objects in arrival order (at least one).
+
+        Raises:
+            TimeoutError:       If no frame arrives within first_timeout.
+            UnexpectedResponse: If any frame has the wrong SUB byte.
+        """
+        frames: list[S3Frame] = []
+        first = self._recv_one(
+            expected_sub=expected_sub,
+            reset_parser=False,
+            timeout=first_timeout,
+        )
+        frames.append(first)
+        while True:
+            try:
+                extra = self._recv_one(
+                    expected_sub=expected_sub,
+                    reset_parser=False,
+                    timeout=batch_timeout,
+                )
+                frames.append(extra)
+            except TimeoutError:
+                break
+        return frames
+
    def _recv_one(
        self,
        expected_sub: Optional[int] = None,
@@ -59,8 +59,9 @@ except ImportError:

 from minimateplus import MiniMateClient
 from minimateplus.protocol import ProtocolError
-from minimateplus.models import ComplianceConfig, DeviceInfo, Event, PeakValues, ProjectInfo, Timestamp
+from minimateplus.models import CallHomeConfig, ComplianceConfig, DeviceInfo, Event, PeakValues, ProjectInfo, Timestamp
 from minimateplus.transport import TcpTransport, DEFAULT_TCP_PORT
+from minimateplus.blastware_file import write_blastware_file, blastware_filename
 from sfm.cache import SFMCache, get_cache
 from sfm.database import SeismoDb

@@ -302,6 +303,27 @@ def _serialise_compliance_config(cc: Optional["ComplianceConfig"]) -> Optional[d
    }


+def _serialise_call_home_config(ch: Optional["CallHomeConfig"]) -> Optional[dict]:
+    if ch is None:
+        return None
+    return {
+        "auto_call_home_enabled":    ch.auto_call_home_enabled,
+        "dial_string":               ch.dial_string,
+        "after_event_recorded":      ch.after_event_recorded,
+        "at_specified_times":        ch.at_specified_times,
+        "time1_enabled":             ch.time1_enabled,
+        "time1_hour":                ch.time1_hour,
+        "time1_min":                 ch.time1_min,
+        "time2_enabled":             ch.time2_enabled,
+        "time2_hour":                ch.time2_hour,
+        "time2_min":                 ch.time2_min,
+        "num_retries":               ch.num_retries,
+        "time_between_retries_sec":  ch.time_between_retries_sec,
+        "wait_for_connection_sec":   ch.wait_for_connection_sec,
+        "warm_up_time_sec":          ch.warm_up_time_sec,
+    }
+
+
 def _serialise_device_info(info: DeviceInfo) -> dict:
    return {
        "serial":             info.serial,
@@ -827,6 +849,109 @@ def device_event_waveform(
    return result


+@app.get("/device/event/{index}/blastware_file")
+def device_event_blastware_file(
+    index:    int,
+    port:     Optional[str] = Query(None,             description="Serial port (e.g. COM5)"),
+    baud:     int           = Query(38400,             description="Serial baud rate"),
+    host:     Optional[str] = Query(None,             description="TCP host — modem IP or ACH relay"),
+    tcp_port: int           = Query(DEFAULT_TCP_PORT, description=f"TCP port (default {DEFAULT_TCP_PORT})"),
+) -> FileResponse:
+    """
+    Download the waveform for a single event (0-based index) and return it
+    as a Blastware-compatible binary file with a correct Blastware filename.
+
+    Supply either *port* (serial) or *host* (TCP/modem).
+
+    The file is written to /tmp and streamed back as a binary download.
+    Blastware can open it directly — filename encodes serial + timestamp.
+
+    Filename format: <prefix><serial3><stem><AB>0<W|H>
+      - prefix letter = chr(ord('B') + floor(serial_numeric / 1000))
+      - stem + AB     = second-resolution timestamp since 1985-01-01 local
+      - W / H         = Full Waveform / Full Histogram (defaults to W for
+                        triggered events; histogram requires recording_mode
+                        to be populated from compliance config)
+
+    Performs: POLL startup → get_events(full_waveform=False, extra_chunks=1,
+    stop_after_index=index) → write_blastware_file() → FileResponse.
+    """
+    log.info(
+        "GET /device/event/%d/blastware_file  port=%s host=%s",
+        index, port, host,
+    )
+
+    try:
+        def _do():
+            with _build_client(port, baud, host, tcp_port, timeout=120.0) as client:
+                info = client.connect()
+                # Use stop_after_metadata=True (full_waveform=False) with 1 extra
+                # chunk after "Project:".  The extra chunk primes the device so that
+                # the termination response carries the full waveform footer bytes.
+                # Without it the terminator returns only ~90 bytes (no useful footer).
+                #
+                # The extra chunk's ADC data IS part of the Blastware file body —
+                # confirmed from 4-27-26 TCP capture: all 14 A5 frames (including the
+                # extra chunk's 2 TCP sub-frames) contribute to the correct 6864-byte
+                # output.  write_blastware_file() includes all frames unconditionally.
+                #
+                # full_waveform=True (natural end-of-stream) downloads ALL chunks
+                # including post-event silence (35+ chunks for a 9-sec event at
+                # 1024 sps) — this produces 24KB+ files that Blastware rejects.
+                events = client.get_events(
+                    full_waveform=False,
+                    stop_after_index=index,
+                    extra_chunks_after_metadata=1,
+                )
+                matching = [ev for ev in events if ev.index == index]
+                return matching[0] if matching else None, info
+        ev, info = _run_with_retry(_do, is_tcp=_is_tcp(host))
+    except HTTPException:
+        raise
+    except ProtocolError as exc:
+        log.error("blastware_file: protocol error: %s", exc, exc_info=True)
+        raise HTTPException(status_code=502, detail=f"Protocol error: {exc}") from exc
+    except OSError as exc:
+        log.error("blastware_file: connection error: %s", exc, exc_info=True)
+        raise HTTPException(status_code=502, detail=f"Connection error: {exc}") from exc
+    except Exception as exc:
+        log.error("blastware_file: unexpected error: %s", exc, exc_info=True)
+        raise HTTPException(status_code=500, detail=f"Device error: {exc}") from exc
+
+    if ev is None:
+        raise HTTPException(
+            status_code=404,
+            detail=f"Event index {index} not found on device",
+        )
+
+    a5_frames = getattr(ev, "_a5_frames", None)
+    if not a5_frames:
+        raise HTTPException(
+            status_code=502,
+            detail=f"No waveform data received for event index {index} — 5A download failed",
+        )
+
+    # Determine serial number from device info
+    serial = getattr(info, "serial", None) or "UNKNOWN"
+
+    # Build filename using the same algorithm Blastware uses
+    filename = blastware_filename(ev, serial)
+
+    # Write to /tmp so FastAPI can stream it back
+    out_path = Path("/tmp") / filename
+    write_blastware_file(ev, a5_frames, out_path)
+    log.info(
+        "blastware_file: wrote %s (%d A5 frames, serial=%s)",
+        out_path, len(a5_frames), serial,
+    )
+
+    return FileResponse(
+        path=str(out_path),
+        filename=filename,
+        media_type="application/octet-stream",
+    )
+
+
 # ── Write endpoints ───────────────────────────────────────────────────────────

 class DeviceConfigBody(BaseModel):
@@ -1075,6 +1200,144 @@ def device_monitor_stop(
    return {"status": "stopped"}


+# ── Call home config endpoints ───────────────────────────────────────────────
+
+
+@app.get("/device/call_home")
+def device_call_home_get(
+    port:     Optional[str] = Query(None,             description="Serial port (e.g. COM5)"),
+    baud:     int           = Query(38400,             description="Serial baud rate"),
+    host:     Optional[str] = Query(None,             description="TCP host — modem IP or ACH relay"),
+    tcp_port: int           = Query(DEFAULT_TCP_PORT, description=f"TCP port (default {DEFAULT_TCP_PORT})"),
+) -> dict:
+    """
+    Read the Auto Call Home (ACH) configuration from the device.
+
+    Sends SUB 0x2C (two-step read) and returns the decoded call home config.
+
+    Confirmed from 4-20-26 call home settings captures (BE11529).
+
+    Returns:
+        {
+          "auto_call_home_enabled": true/false,
+          "dial_string": "RADIO RING",
+          "after_event_recorded": true/false,
+          "at_specified_times": true/false,
+          "time1_enabled": true/false, "time1_hour": 19, "time1_min": 55,
+          "time2_enabled": false, "time2_hour": 0, "time2_min": 0,
+          "num_retries": 3,
+          "time_between_retries_sec": 15,
+          "wait_for_connection_sec": 60,
+          "warm_up_time_sec": 60
+        }
+    """
+    try:
+        def _do():
+            with _build_client(port, baud, host, tcp_port) as client:
+                client.poll()
+                return client.get_call_home_config()
+        ch_config = _run_with_retry(_do, is_tcp=_is_tcp(host))
+    except HTTPException:
+        raise
+    except ProtocolError as exc:
+        raise HTTPException(status_code=502, detail=f"Protocol error: {exc}") from exc
+    except OSError as exc:
+        raise HTTPException(status_code=502, detail=f"Connection error: {exc}") from exc
+    except Exception as exc:
+        raise HTTPException(status_code=500, detail=f"Device error: {exc}") from exc
+
+    return _serialise_call_home_config(ch_config) or {}
+
+
+class CallHomeConfigBody(BaseModel):
+    """
+    Request body for POST /device/call_home.
+
+    All fields are optional — only supplied (non-null) fields are modified.
+    All other call home config bytes are round-tripped verbatim from the device.
+
+    Confirmed writable fields (4-20-26 captures):
+      auto_call_home_enabled : bool  — master enable for auto call home
+      after_event_recorded   : bool  — call home after each triggered event
+      at_specified_times     : bool  — enable time-based scheduled calls
+      time1_enabled          : bool  — enable time slot 1
+      time1_hour             : int   — hour for slot 1 (0-23; avoid 3 — DLE escape limitation)
+      time1_min              : int   — minute for slot 1 (0-59; avoid 3)
+      time2_enabled          : bool  — enable time slot 2
+      time2_hour             : int   — hour for slot 2 (0-23; avoid 3)
+      time2_min              : int   — minute for slot 2 (0-59; avoid 3)
+
+    Read-only fields (not writable via this endpoint):
+      dial_string, num_retries, time_between_retries_sec,
+      wait_for_connection_sec, warm_up_time_sec
+    """
+    auto_call_home_enabled: Optional[bool]  = None
+    after_event_recorded:   Optional[bool]  = None
+    at_specified_times:     Optional[bool]  = None
+    time1_enabled:          Optional[bool]  = None
+    time1_hour:             Optional[int]   = None
+    time1_min:              Optional[int]   = None
+    time2_enabled:          Optional[bool]  = None
+    time2_hour:             Optional[int]   = None
+    time2_min:              Optional[int]   = None
+
+
+@app.post("/device/call_home")
+def device_call_home_set(
+    body:     CallHomeConfigBody,
+    port:     Optional[str] = Query(None,             description="Serial port (e.g. COM5)"),
+    baud:     int           = Query(38400,             description="Serial baud rate"),
+    host:     Optional[str] = Query(None,             description="TCP host — modem IP or ACH relay"),
+    tcp_port: int           = Query(DEFAULT_TCP_PORT, description=f"TCP port (default {DEFAULT_TCP_PORT})"),
+) -> dict:
+    """
+    Read the current call home config, apply supplied changes, and write back.
+
+    Only non-null fields are modified.  All other bytes round-trip verbatim.
+
+    Write sequence (confirmed from 4-20-26 call home settings captures):
+      SUB 0x2C (read 2-step) → 125-byte raw payload
+      patch fields
+      SUB 0x7E (write 127-byte payload) → ack 0x81
+      SUB 0x7F (confirm) → ack 0x80
+
+    Example body:
+        { "auto_call_home_enabled": true, "after_event_recorded": true,
+          "time1_enabled": true, "time1_hour": 20, "time1_min": 0 }
+    """
+    changed = body.model_dump(exclude_none=True)
+    log.info("POST /device/call_home  port=%s host=%s  fields=%s", port, host, list(changed.keys()))
+
+    try:
+        def _do():
+            with _build_client(port, baud, host, tcp_port) as client:
+                client.poll()
+                client.set_call_home_config(
+                    auto_call_home_enabled=body.auto_call_home_enabled,
+                    after_event_recorded=body.after_event_recorded,
+                    at_specified_times=body.at_specified_times,
+                    time1_enabled=body.time1_enabled,
+                    time1_hour=body.time1_hour,
+                    time1_min=body.time1_min,
+                    time2_enabled=body.time2_enabled,
+                    time2_hour=body.time2_hour,
+                    time2_min=body.time2_min,
+                )
+        _run_with_retry(_do, is_tcp=_is_tcp(host))
+    except HTTPException:
+        raise
+    except ProtocolError as exc:
+        raise HTTPException(status_code=502, detail=f"Protocol error: {exc}") from exc
+    except OSError as exc:
+        raise HTTPException(status_code=502, detail=f"Connection error: {exc}") from exc
+    except ValueError as exc:
+        raise HTTPException(status_code=422, detail=str(exc)) from exc
+    except Exception as exc:
+        raise HTTPException(status_code=500, detail=f"Device error: {exc}") from exc
+
+    return {"status": "ok", "updated_fields": changed}
+
+
 # ── Cache management endpoints ────────────────────────────────────────────────

@app.get("/cache/stats")
@@ -739,6 +739,7 @@
  <button class="tab-btn active" data-tab="device"    onclick="switchTab('device')">Device</button>
  <button class="tab-btn"        data-tab="events"    onclick="switchTab('events')">Events</button>
  <button class="tab-btn"        data-tab="config"    onclick="switchTab('config')">Config</button>
+  <button class="tab-btn"        data-tab="call-home" onclick="switchTab('call-home')">Call Home</button>
 </div>

 <!-- ════════════════════════════════════════════════════════════════
@@ -909,6 +910,123 @@

  </div><!-- end #tab-config -->

+<!-- ════════════════════════════════════════════════════════════════
+     TAB: Call Home
+═══════════════════════════════════════════════════════════════════ -->
+<div id="tab-call-home" class="tab-pane">
+
+  <div class="cfg-grid">
+
+    <!-- Enable / dial -->
+    <div class="cfg-section">
+      <div class="cfg-section-title">Auto Call Home</div>
+
+      <div class="cfg-field">
+        <label>Enable Auto Call Home</label>
+        <select id="ch-enabled">
+          <option value="">— unchanged —</option>
+          <option value="true">Enabled</option>
+          <option value="false">Disabled</option>
+        </select>
+      </div>
+
+      <div class="cfg-field">
+        <label>Dial String</label>
+        <input type="text" id="ch-dial-string" disabled placeholder="Read-only (e.g. RADIO RING)" />
+        <div class="hint">Read from device — not writable via this interface</div>
+      </div>
+
+      <div class="cfg-section-title" style="margin-top:16px">When to Call</div>
+
+      <div class="cfg-field">
+        <label>After Event Recorded</label>
+        <select id="ch-after-event">
+          <option value="">— unchanged —</option>
+          <option value="true">Yes</option>
+          <option value="false">No</option>
+        </select>
+      </div>
+
+      <div class="cfg-field">
+        <label>At Specified Times</label>
+        <select id="ch-at-times">
+          <option value="">— unchanged —</option>
+          <option value="true">Yes</option>
+          <option value="false">No</option>
+        </select>
+      </div>
+
+    </div>
+
+    <!-- Scheduled call times -->
+    <div class="cfg-section">
+      <div class="cfg-section-title">Scheduled Call Times</div>
+
+      <div class="cfg-field">
+        <label>Time Slot 1</label>
+        <div style="display:flex;gap:8px;align-items:center">
+          <select id="ch-t1-enabled" style="width:120px">
+            <option value="">— enable —</option>
+            <option value="true">Enabled</option>
+            <option value="false">Disabled</option>
+          </select>
+          <input type="number" id="ch-t1-hour" min="0" max="23" step="1" placeholder="HH" style="width:64px" />
+          <span>:</span>
+          <input type="number" id="ch-t1-min"  min="0" max="59" step="1" placeholder="MM" style="width:64px" />
+        </div>
+        <div class="hint">Hour (0-23) and minute (0-59).  Avoid value 3 (DLE limitation).</div>
+      </div>
+
+      <div class="cfg-field">
+        <label>Time Slot 2</label>
+        <div style="display:flex;gap:8px;align-items:center">
+          <select id="ch-t2-enabled" style="width:120px">
+            <option value="">— enable —</option>
+            <option value="true">Enabled</option>
+            <option value="false">Disabled</option>
+          </select>
+          <input type="number" id="ch-t2-hour" min="0" max="23" step="1" placeholder="HH" style="width:64px" />
+          <span>:</span>
+          <input type="number" id="ch-t2-min"  min="0" max="59" step="1" placeholder="MM" style="width:64px" />
+        </div>
+        <div class="hint">Hour (0-23) and minute (0-59).  Avoid value 3 (DLE limitation).</div>
+      </div>
+
+      <div class="cfg-section-title" style="margin-top:16px">Retry Settings (read-only)</div>
+
+      <div class="cfg-field">
+        <label>Number of Retries</label>
+        <input type="text" id="ch-num-retries" disabled placeholder="—" />
+      </div>
+
+      <div class="cfg-field">
+        <label>Time Between Retries (s)</label>
+        <input type="text" id="ch-retry-gap" disabled placeholder="—" />
+      </div>
+
+      <div class="cfg-field">
+        <label>Wait for Connection (s)</label>
+        <input type="text" id="ch-wait-conn" disabled placeholder="—" />
+      </div>
+
+      <div class="cfg-field">
+        <label>Warm-up Time (s)</label>
+        <input type="text" id="ch-warmup" disabled placeholder="—" />
+      </div>
+
+    </div>
+
+  </div>
+
+  <div class="cfg-actions">
+    <button class="btn btn-ghost" id="ch-read-btn" onclick="readCallHome()" disabled>Read from Device</button>
+    <button class="btn btn-success" id="ch-write-btn" onclick="writeCallHome()" disabled>Write to Device</button>
+    <button class="btn btn-ghost" onclick="clearCallHomeForm()">Clear Form</button>
+    <span id="ch-status"></span>
+  </div>
+
+</div><!-- end #tab-call-home -->
+
 </div><!-- end #section-live -->

 <!-- ════════════════════════════════════════════════════════════════
@@ -1192,6 +1310,8 @@ async function connectUnit() {
  document.getElementById('next-btn').disabled  = eventList.length <= 1;
  document.getElementById('cfg-read-btn').disabled  = false;
  document.getElementById('cfg-write-btn').disabled = false;
+  document.getElementById('ch-read-btn').disabled   = false;
+  document.getElementById('ch-write-btn').disabled  = false;

  btn.disabled = false; btn.textContent = 'Reconnect';

@@ -1494,6 +1614,134 @@ async function writeConfig() {
  }
 }

+// ── Call Home form ─────────────────────────────────────────────────────────────
+function setChStatus(msg, type) {
+  const el = document.getElementById('ch-status');
+  el.textContent = msg;
+  el.style.color = type === 'ok' ? '#4caf50' : type === 'error' ? '#f44336' : '#aaa';
+}
+
+function populateCallHomeForm(ch) {
+  if (!ch) return;
+  const qs2 = id => document.getElementById(id);
+
+  // Read-only display fields
+  if (ch.dial_string != null)          qs2('ch-dial-string').value = ch.dial_string || '';
+  if (ch.num_retries != null)          qs2('ch-num-retries').value = ch.num_retries;
+  if (ch.time_between_retries_sec != null) qs2('ch-retry-gap').value = ch.time_between_retries_sec;
+  if (ch.wait_for_connection_sec != null)  qs2('ch-wait-conn').value = ch.wait_for_connection_sec;
+  if (ch.warm_up_time_sec != null)     qs2('ch-warmup').value = ch.warm_up_time_sec;
+
+  // Editable select/input fields (use "" for "unchanged" state when value is null)
+  function setBool(id, val) {
+    if (val != null) document.getElementById(id).value = val ? 'true' : 'false';
+  }
+  setBool('ch-enabled',    ch.auto_call_home_enabled);
+  setBool('ch-after-event', ch.after_event_recorded);
+  setBool('ch-at-times',    ch.at_specified_times);
+  setBool('ch-t1-enabled',  ch.time1_enabled);
+  setBool('ch-t2-enabled',  ch.time2_enabled);
+  if (ch.time1_hour != null) qs2('ch-t1-hour').value = ch.time1_hour;
+  if (ch.time1_min  != null) qs2('ch-t1-min').value  = ch.time1_min;
+  if (ch.time2_hour != null) qs2('ch-t2-hour').value = ch.time2_hour;
+  if (ch.time2_min  != null) qs2('ch-t2-min').value  = ch.time2_min;
+}
+
+function clearCallHomeForm() {
+  ['ch-enabled','ch-after-event','ch-at-times','ch-t1-enabled','ch-t2-enabled']
+    .forEach(id => { document.getElementById(id).selectedIndex = 0; });
+  ['ch-t1-hour','ch-t1-min','ch-t2-hour','ch-t2-min']
+    .forEach(id => { document.getElementById(id).value = ''; });
+  // Keep read-only display fields but clear them too
+  ['ch-dial-string','ch-num-retries','ch-retry-gap','ch-wait-conn','ch-warmup']
+    .forEach(id => { document.getElementById(id).value = ''; });
+  setChStatus('');
+}
+
+async function readCallHome() {
+  if (!devHost()) { setChStatus('Not connected.', 'error'); return; }
+  setChStatus('Reading call home config from device…');
+  document.getElementById('ch-read-btn').disabled = true;
+  try {
+    const r = await fetch(`${api()}/device/call_home?${deviceParams()}`);
+    if (!r.ok) { const e = await r.json().catch(()=>({})); throw new Error(e.detail || r.statusText); }
+    const ch = await r.json();
+    populateCallHomeForm(ch);
+    setChStatus('Call home config loaded from device.', 'ok');
+  } catch(e) {
+    setChStatus(`Read failed: ${e.message}`, 'error');
+  } finally {
+    document.getElementById('ch-read-btn').disabled = false;
+  }
+}
+
+async function writeCallHome() {
+  if (!devHost()) { setChStatus('Not connected.', 'error'); return; }
+
+  // Build body — only include fields that have values
+  const body = {};
+
+  function getBool(id) {
+    const v = document.getElementById(id).value;
+    return v === '' ? null : v === 'true';
+  }
+  function getIntField(id) {
+    const v = document.getElementById(id).value.trim();
+    return v === '' ? null : parseInt(v, 10);
+  }
+
+  const en = getBool('ch-enabled');
+  if (en !== null) body.auto_call_home_enabled = en;
+  const ae = getBool('ch-after-event');
+  if (ae !== null) body.after_event_recorded = ae;
+  const at = getBool('ch-at-times');
+  if (at !== null) body.at_specified_times = at;
+  const t1e = getBool('ch-t1-enabled');
+  if (t1e !== null) body.time1_enabled = t1e;
+  const t1h = getIntField('ch-t1-hour');
+  if (t1h !== null) body.time1_hour = t1h;
+  const t1m = getIntField('ch-t1-min');
+  if (t1m !== null) body.time1_min = t1m;
+  const t2e = getBool('ch-t2-enabled');
+  if (t2e !== null) body.time2_enabled = t2e;
+  const t2h = getIntField('ch-t2-hour');
+  if (t2h !== null) body.time2_hour = t2h;
+  const t2m = getIntField('ch-t2-min');
+  if (t2m !== null) body.time2_min = t2m;
+
+  if (Object.keys(body).length === 0) {
+    setChStatus('No fields to write — change at least one field.', 'error');
+    return;
+  }
+
+  // Warn about value 3 in hour/min fields
+  const hourMinFields = [body.time1_hour, body.time1_min, body.time2_hour, body.time2_min];
+  if (hourMinFields.some(v => v === 3)) {
+    setChStatus('Error: value 3 in hour/minute fields is not supported (DLE protocol limitation).', 'error');
+    return;
+  }
+
+  const fieldsStr = Object.keys(body).join(', ');
+  setChStatus(`Writing ${Object.keys(body).length} field(s)…`);
+  document.getElementById('ch-write-btn').disabled = true;
+
+  try {
+    const r = await fetch(`${api()}/device/call_home?${deviceParams()}`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify(body),
+    });
+    if (!r.ok) { const e = await r.json().catch(()=>({})); throw new Error(e.detail || r.statusText); }
+    setChStatus(`Written: ${fieldsStr}`, 'ok');
+    // Re-read to confirm changes
+    await readCallHome();
+  } catch(e) {
+    setChStatus(`Write failed: ${e.message}`, 'error');
+  } finally {
+    document.getElementById('ch-write-btn').disabled = false;
+  }
+}
+
 // ── Events ─────────────────────────────────────────────────────────────────────
 function populateEventChips() {
  const el = document.getElementById('event-chips');
Author	SHA1	Message	Date
claude	e1a6fd5386	fix(protocol): remove auto-detection of frame mode and ensure extra chunks are always used for valid waveform footer	2026-04-28 00:05:51 -04:00
claude	6b875e161b	fix(protocol): implement auto-detection of frame mode based on probe response size for accurate chunk handling	2026-04-27 23:29:53 -04:00
claude	f5c81f2cab	fix: add new helper (_recv_5a_batch()) that helps with assembling chunks over TCP	2026-04-27 18:39:34 -04:00
claude	a7585cb5e0	fix(blastware_file, server): implement logic to skip extra chunks after metadata for accurate file writing	2026-04-26 16:32:32 -04:00
claude	ae30a02898	fix(blastware_file, server): enhance logging and correct chunk handling for accurate data processing	2026-04-26 16:03:07 -04:00
claude	2f084ed105	fix(protocol): update chunk counter formula to use max(key4[2:4], 0x0400) for accurate data streaming	2026-04-26 01:28:47 -04:00
claude	7976b544ed	fix(blastware_file): never skip A5 frames based on classification at fi>0 Frame 0 is always the probe; frames 1+ are always data (waveform ADC chunks, compliance config, compliance continuation). Gating on classify_frame() at fi>0 produces false positives: ADC binary data can coincidentally contain b"STRT\xff\xfe", causing frames 1 and 5 to be silently dropped from the body (confirmed from live capture on event key=01110000). Remove all type-based filtering; include every frame unconditionally with the standard index-based skip amounts.	2026-04-26 00:59:36 -04:00
claude	0415af19b4	fix(blastware_file): remove seen_metadata flag and adjust frame processing logic	2026-04-24 20:21:03 -04:00
claude	35c3f4f945	fix(protocol): correct A5 frame classification and chunk counter formula	2026-04-24 17:25:29 -04:00
claude	43c8158493	feat(blastware_file): classify A5 frames, only write waveform frames to body Add classify_frame() which categorises each A5 frame by content: terminator — page_key == 0x0000 probe_or_strt — contains b"STRT" metadata — contains compliance-config ASCII markers (Project:, Client:, Standard Recording Setup, …) waveform — binary-heavy (< 20% printable ASCII), i.e. raw ADC data unknown — fallback Update write_blastware_file() body loop: frame 0 (probe) is still always processed; frames 1+ are only included when classify_frame returns "waveform". Metadata frames (compliance config block with Project:/Client:/etc.) and any stray STRT-bearing frames are skipped with a warning/debug log. Terminator frame handling is unchanged. Adds temporary print() diagnostics so each frame's classification is visible in the server log to aid debugging. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>	2026-04-24 15:48:37 -04:00
claude	242666f358	fix(protocol): correct chunk counter formula for accurate data streaming	2026-04-24 12:52:02 -04:00
claude	03540fdc00	fix: raise max_chunks to 128 for metadata-only 5A download For 2-second events at 1024 sps the "Project:" metadata frame appears beyond chunk 32 (the old default cap), causing the safety limit to be hit and ~34 KB of waveform data to be downloaded instead of stopping at the metadata frame. Raising max_chunks to 128 ensures stop_after_metadata=True can locate the metadata frame for record times up to ~4 seconds. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>	2026-04-24 02:19:27 -04:00
claude	f83fd880c0	fix(protocol): update device_event_blastware_file to include extra chunk for accurate data retrieval	2026-04-24 00:35:34 -04:00
claude	ab2c11e9a9	fix(protocol): refine extra chunk fetching logic for accurate termination response	2026-04-23 20:30:07 -04:00
claude	fa887b85d9	fix(protocol): update extra chunk fetching logic to stop at silence detection	2026-04-23 18:28:14 -04:00
claude	ecd980d345	fix(protocol): enhance extra chunk fetching logic to ensure footer detection	2026-04-23 18:22:27 -04:00
claude	bc9f16e503	fix(protocol): adjust extra_chunks calculation to use integer conversion of record_time	2026-04-23 17:39:28 -04:00
claude	aa2b02535b	fix(protocol): add record_time based chunk scaling for longer event record times	2026-04-23 17:33:16 -04:00
claude	2a2031c3a9	fix(protocol): fetch additional chunk after metadata to ensure valid termination response	2026-04-23 17:08:36 -04:00
claude	9e7e0bce2a	fix(protocol): adjust full_waveform setting for event downloads to end when it should.	2026-04-23 16:43:59 -04:00
claude	5e2f3bf2a1	fix(protocol): enable full_waveform for continuous mode.	2026-04-23 16:24:39 -04:00
claude	39ebd4bdaa	fix(protocol): revert endpoint back to stop_after_metadata=True	2026-04-23 15:11:56 -04:00
claude	84c87d0b57	fix(protocol): adjust waveform download to use full_waveform for accurate event streaming	2026-04-23 13:02:55 -04:00
claude	ec6362cb8e	fix(protocol): include terminator in waveform stream downloads	2026-04-23 12:45:59 -04:00
claude	3eeafd24aa	fix(protocol): improve terminator frame detection in write_blastware_file. fix: rename .n00 to just blastware file (.n00 was false positive)	2026-04-23 01:33:44 -04:00
claude	8cb8b86192	fix(server): add error logging for device event handling	2026-04-22 23:48:59 -04:00
claude	6dcca4da79	feat(protocol): fully decode Blastware filename encoding and update related documentation	2026-04-22 23:43:31 -04:00
claude	c47e3a3af0	feat(protocol): update Blastware file format documentation and encoding details	2026-04-22 19:16:05 -04:00
claude	dfbc9f29c5	feat: first try at building waveform binary files.	2026-04-21 22:57:53 -04:00
claude	4331215e23	feat(protocol): enhance raw capture functionality and documentation updates - Update `s3_bridge.py` to default raw capture file paths to "auto" for timestamped naming. - Modify `gui_bridge.py` to pre-check raw capture options and streamline path handling. - Extend `ach_server.py` to save both incoming and outgoing raw bytes for analysis. - Revise `CHANGELOG.md` and `instantel_protocol_reference.md` to reflect changes in recording mode handling and compliance data encoding.	2026-04-21 16:07:24 -04:00
claude	b3dcfe7239	fix(client): correct recording_mode anchor position in compliance config encoding	2026-04-21 01:17:45 -04:00
claude	9b5cdfd857	feat(logging): add detailed logging for anchor position in compliance config encoding/decoding	2026-04-21 00:23:15 -04:00
claude	7129aae279	fix(client): update compliance data size handling (less strict now)	2026-04-21 00:09:30 -04:00
claude	2186bc238b	fix: call home settings tab display	2026-04-20 21:15:16 -04:00
claude	3fb24e1895	feat(call-home): Implement Auto Call Home configuration management - Added `CallHomeConfig` model to represent the Auto Call Home settings. - Introduced methods in `MiniMateClient` for reading (`get_call_home_config`) and writing (`set_call_home_config`) the call home configuration. - Updated `MiniMateProtocol` with new commands for call home operations (SUB 0x2C for read, SUB 0x7E for write, and SUB 0x7F for confirm). - Created API endpoints for retrieving and updating call home settings in the server. - Enhanced the web interface with a new "Call Home" tab for user interaction with call home settings. - Implemented JavaScript functions for reading and writing call home configurations from the web app.	2026-04-20 18:23:48 -04:00