seismo-relay/CLAUDE.md

CLAUDE.md — seismo-relay

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: v0.17.0.

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

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Project layout

minimateplus/         ← Python client library (primary focus)
  transport.py        ←   SerialTransport, TcpTransport
  framing.py          ←   DLE codec, frame builders, S3FrameParser
  protocol.py         ←   MiniMateProtocol — wire-level read/write methods
  client.py           ←   MiniMateClient — high-level API (connect, get_events, …)
  models.py           ←   DeviceInfo, EventRecord, ComplianceConfig, …
  waveform_codec.py   ←   Body-codec block walker + decode_tran_initial (partial
                          per-sample decoder — see "Waveform body codec" section below)

sfm/server.py         ← FastAPI REST server exposing device data over HTTP
seismo_lab.py         ← Tkinter GUI (Bridge + Analyzer + Console tabs)
docs/
  instantel_protocol_reference.md  ← reverse-engineered protocol spec ("the Rosetta Stone")
CHANGELOG.md          ← version history

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Current implementation state (v0.14.3)

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

Step	SUB	Status
POLL / startup handshake	5B	✅
Serial number	15	✅
Full config (firmware, calibration date, etc.)	FE	✅
Compliance config (record time, sample rate, geo thresholds)	1A	✅
Event index	08	✅
Event header / first key	1E	✅
Waveform header	0A	✅
Waveform record (peaks, timestamp, project)	0C	✅
Bulk waveform stream (event-time metadata + full waveform)	5A	✅ byte-perfect against BW captures (v0.14.3, 2026-05-05) — STRT-bounded chunk walk + correct event-N probe counter + DLE-stuffed 0x10 bytes in params + concatenate-only file body assembly. All 17 5A request frames in the 5-1-26 3-sec capture reproduce byte-for-byte.
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
Auto Call Home config (read + write)	2C → 7E → 7F	✅ new v0.12.3

get_events() sequence per event: 1E → 0A → 1E(arm token=0xFE) → 0C → 1F(arm) → POLL×3 → 5A → 1F(browse) (see "Correct iteration pattern" section below for full detail)

push_config_raw() write sequence: 68→73 | 71×3→72 | 82→83 | 69→74→72

delete_all_events() erase sequence: 0xA3 → 0x1C → 0x06 → 0xA2

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Waveform body codec — PARTIAL (2026-05-11)

The per-byte decoding of the Blastware waveform-file body (between the 21-byte STRT record and the 26-byte footer) was historically claimed to be "raw int16 LE, 8 bytes per sample-set." That was wrong — see the retraction in docs/instantel_protocol_reference.md §7.6.1. The body is actually a tagged-block stream with a custom delta+RLE codec.

What's solved (2026-05-11)

• Block framing — 5 tag types (10 NN, 20 NN, 00 NN, 30 NN, 40 02) with confirmed lengths. Implementation: walk_body() in minimateplus/waveform_codec.py.
• Tran channel segment 0 — preamble bytes [3:7] = Tran[0], Tran[1] as int16 BE in 16-count units (LSB = 0.005 in/s). Then 10 NN (4-bit nibble deltas), 20 NN (int8 deltas), and 00 NN (RLE zero deltas) carry Tran deltas from sample 2 onward. Verified byte-perfect across 4 of 5 fixture events (510 samples each). Implementation: decode_tran_initial().
• Segment header — 40 02 is a 20-byte block. Payload bytes [0:2] are the T_delta at the start of the new segment (int16 BE). Bytes [6:8] are the byte length to the next segment header. Bytes [8:12] are a monotonic uint32 LE counter. Bytes [12:14] are constant 02 00.

What's NOT solved

• Tran past segment 0 — multi-segment Tran continuation has been attempted but every hypothesis tested breaks at sample ~512. Likely channels rotate across segments (e.g. segment 0 = Tran, segment 1 = Vert, …) but this is unverified.
• Vert / Long / Mic channels — no per-channel decoder yet. These almost certainly live in later segments but the segment-to-channel mapping is open.
• The 30 NN block content — appears in loud-from-start events (SS0, SV0) and breaks the simple Tran walk there. Probably a channel- switch or alternative-encoding marker for high-amplitude regions.

Production-code status

client.py:_decode_a5_waveform still uses the old (broken) int16 LE decoder. Until the multi-channel decoder lands, the .h5 sidecars produced by SFM contain WRONG samples — keep treating them as "unverified" downstream. decode_waveform_v2() returns None as a placeholder.

Test fixtures

tests/fixtures/decode-re-5-8-26/ and tests/fixtures/5-11-26/ — seven BW binary + ASCII pairs captured from a live BE11529. The 5-11-26 high-amplitude bundle (PPV 6–7 in/s) is what cracked the Tran codec; the V70 (mic-heavy) + JQ0 (Vert-heavy) pair cracked the 00 NN RLE rule.

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Protocol fundamentals

DLE framing

BW→S3 (our requests):   [ACK=0x41] [STX=0x02] [stuffed payload+chk] [ETX=0x03]
S3→BW (device replies): [DLE=0x10] [STX=0x02] [stuffed payload+chk] [bare ETX=0x03]

• DLE stuffing rule: any literal 0x10 byte in the payload is doubled on the wire (0x10 → 0x10 0x10). This includes the checksum byte.
• Inner-frame terminators: large S3 responses (A4, E5) contain embedded sub-frames using DLE+ETX as inner terminators. The outer parser treats DLE+ETX inside a frame as literal data — the bare ETX is the ONLY real frame terminator.
• Response SUB rule: response_SUB = 0xFF - request_SUB (no known exceptions — earlier note claiming 1C → 6E was WRONG; 1C → 0xE3 confirmed across 338 frames in 4-8-26 captures)
• Two-step read pattern: every read command is sent twice — probe step (offset=0x00, get length) then data step (offset=DATA_LENGTH, get payload). All data lengths are hardcoded constants, not read from the probe response.

De-stuffed payload header

BW→S3 (request):
  [0] CMD    0x10
  [1] flags  0x00
  [2] SUB    command byte
  [3] 0x00   always zero
  [4] 0x00   always zero
  [5] OFFSET 0x00 for probe step; DATA_LENGTH for data step
  [6-15]     params (key, token, etc. — see helpers in framing.py)

S3→BW (response):
  [0] CMD    0x00
  [1] flags  0x10
  [2] SUB    response sub byte
  [3] PAGE_HI
  [4] PAGE_LO
  [5+] data

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Critical protocol gotchas (hard-won — do not re-derive)

SUB 5A — bulk waveform stream — NON-STANDARD frame format

Always use build_5a_frame() for SUB 5A. Never use build_bw_frame() for SUB 5A.

build_bw_frame produces WRONG output for 5A for two reasons:

1. offset_hi = 0x10 must NOT be DLE-stuffed. Blastware sends the offset field raw. build_bw_frame would stuff it to 10 10 on the wire — the device silently ignores the frame. build_5a_frame writes it as a bare 10.

2. DLE-aware checksum. When computing the checksum, 10 XX pairs in the stuffed section contribute only XX to the running sum; lone bytes contribute normally. This differs from the standard SUM8-of-destuffed-payload that all other commands use.

3. Params region uses partial DLE stuffing (CONFIRMED 2026-05-05). The device's de-stuffing rule for bytes inside the params region is:

   • 10 10 → de-stuffs to 10
   • 10 02 / 03 / 04 → kept literal (these are inner-frame markers)
   • 10 X for other X → de-stuffs to just X (drops the leading 0x10)

   Therefore any 0x10 byte in the logical params that is followed by a byte NOT in {0x02, 0x03, 0x04, 0x10} MUST be doubled on the wire (10 X → 10 10 X) so the device's de-stuffer reproduces the original 10 X pair. This applies most commonly to counters with 0x10 in the high byte (e.g. counter=0x1000 produces logical params bytes ... 10 00 ..., which BW encodes on the wire as ... 10 10 00 ...). Without this stuffing the device interprets counter=0x1000 as 0x0000 and returns the probe response (which contains a copy of the file header + STRT record). That STRT block then gets embedded in the assembled file body at offset 0x1016, and Blastware refuses to open the file — see the v0.14.3 entry in CHANGELOG.md.

   0x10 bytes in offset_hi (body[5]) are still written RAW — only the params region has this stuffing requirement. The metadata-page params for counter 0x1002 / 0x1004 survive without stuffing because 10 02 and 10 04 fall in the "kept literal" carve-out.

Both differences (1) and (2) confirmed by reproducing Blastware's exact wire bytes from the 1-2-26 BW TX capture (10 frames). Difference (3) confirmed against the 5-1-26 "bwcap3sec" capture (17 frames, all match byte-for-byte after fix).

SUB 5A — chunk counter formula (REWRITTEN 2026-05-01 — see 5-1-26 captures)

⚠️ Everything that came before this rewrite was WRONG in important ways. The previous formula max(key4[2:4], 0x0400) + (chunk_num - 1) * 0x0400 happened to work for events at start_key=0 because the device responds to whatever counter you ask for — but it caused a 5× over-read past the actual event, picking up post-event circular-buffer garbage that corrupts the reconstructed file for any event > ~1 sec of waveform. The captures in bridges/captures/4-27-26/ and 5-1-26/comcheck/ show BW reads only ~12-16 chunks for the same events SFM was reading 37+ chunks for. See "TERM frame" and "STRT end_offset" sections below for the actual mechanism.

Chunk addressing is just absolute device-buffer addresses.

params[0]=0x00, params[1:5] is a 4-byte absolute device flash-buffer address (= the "key" of that location), params[5:11] are zeros. The device returns 0x0200 (= 512) bytes starting at that address. Increments between consecutive chunks are 0x0200 (NOT 0x0400) — this matches the chunk payload size. The previous "0x0400 step" worked by accident: BW asks for half-size chunks; SFM was asking for double-size chunks, both with the same-named "counter" field, but the value is just an address pointer the device honors as-is.

The chunk pattern depends on whether the event sits at start_key=0 or not.

Event 1 case — start_key[2:4] == 0x0000 (first event after erase / wrap)

1.  Probe at counter=0x0000           (params[1:5] = full key, returns STRT record)
2.  Read 2 fixed metadata pages:      counter=0x1002, counter=0x1004
                                       (these are GLOBAL session metadata — read ONCE per
                                        Blastware session, not per event; contain the
                                        Project/Client/User Name/Seis Loc strings)
3.  Sample chunks:                    counter=0x0600, 0x0800, …, by 0x0200 increment,
                                       up to but not including end_offset (rounded down to
                                       0x0200 boundary)
4.  TERM frame                         (see TERM formula below)

The reason 0x0046..0x0600 is skipped for event 1 is unknown — likely some pre-event firmware reserved area for the first slot in a freshly-erased buffer. Harmless to skip.

Event 2+ case — start_key[2:4] != 0x0000 (continuation events)

1.  First chunk at counter = start_key[2:4]              (this IS the probe — response
                                                          contains STRT at byte 17)
2.  Sample chunks:                                       counter += 0x0200 each, up to but
                                                          not including end_offset
3.  TERM frame

start_key here is the off=0x46 WAVEHDR record key returned by 1F (e.g. 01112238), NOT the off=0x2C boundary key that immediately precedes it. An earlier draft of this doc described event-N as "probe at start + 0x46" — that formula came from naming the boundary key as start_key. In the iteration walk, cur_key passed to read_bulk_waveform_stream is always the off=0x46 key (the partial-record skip path in get_events re-runs 1F to advance past boundary records before invoking 5A), so the probe counter is just cur_key[2:4] with no extra offset. Adding +0x46 caused the probe to overshoot, miss the STRT record at byte 17 of the response, fall back to the max_chunks=128 cap, and walk ~110 chunks of post-event garbage — observed in SFM 5-4-26 capture before the fix.

Confirmed across:

• 5-1-26 "copy 2nd address" BW capture: probe counter=0x2238, key=01112238, STRT@17 end=0x417E.
• 5-4-26 BW 2-sec event capture: probe counter=0x2238, key=01112238, TERM offset_word=0x0146 → end=0x417E.

No metadata pages — those have already been read during event 1 in the same Blastware session, and BW caches them. Note that the metadata-page reads happen ONCE per Blastware-session-on-the-device, not once per event, so an SFM session that downloads several events should read 0x1002/0x1004 only once at the start.

History (do not re-derive)

• Original: _CHUNK1_COUNTER = 0x1004 hardcoded (Blastware capture artifact — WRONG).
• 2026-04-06: chunk_num * 0x0400 (worked for key 01110000 only).
• 2026-04-24: key4[2:4] + (chunk_num-1) * 0x0400 (fixed non-zero offsets, broke key 01110000).
• 2026-04-26: max(key4[2:4], 0x0400) + (chunk_num-1) * 0x0400 (broken — over-read past event end).
• 2026-05-01: Increments are 0x0200 not 0x0400; absolute addresses inside event range; bounded by STRT end_key, not by max_chunks cap or device-side timeout.
• 2026-05-04: Removed spurious +0x0046 from event-N probe counter. cur_key from 1F is already the off=0x46 WAVEHDR key, so adding +0x46 would have placed the probe one WAVEHDR past the actual event start. This caused probe responses to lack a STRT record (no end_offset parsed → 0xFFFF fallback → max_chunks=128 cap), walking ~110 chunks of post-event circular-buffer garbage. Fixed in protocol.py read_bulk_waveform_stream.

SUB 5A — STRT record encodes end_offset (NEW 2026-05-01)

The first A5 response (probe response, or the first chunk for event 2+) contains a STRT record at byte offset 17 of the data field. Layout:

data[17:21]   "STRT"          magic
data[21:23]   ff fe           sentinel
data[23:27]   end_key          ← 4-byte key of where this event ENDS
data[27:31]   start_key        ← 4-byte key of where this event STARTS
data[31:33]   uint16 BE        ?? sample-count or total bytes (varies; not yet decoded)
data[33:35]   uint16 BE        ??
data[35]      0x46             record type (waveform full record)
…

end_offset = (end_key[2] << 8) | end_key[3] is the authoritative event-end pointer. SFM must extract this from the first A5 response and use it to bound the chunk loop and encode the TERM frame. The device will happily respond to chunk requests past end_offset (returning post-event circular-buffer contents) — that's the over-read bug.

Verified across 3 events:

Capture	start_key	end_key	end_offset	event size
4-27-26 "open 2sec" / "copy event to disk"	01110000	01111ABE	0x1ABE	6,846 B
5-1-26 "copy 3sec" / Download All event 1	01110000	011121F2	0x21F2	8,690 B
5-1-26 "copy 2nd address" / DA event 2	011121F2	0111417E	0x417E (event 2 span 0x1F8C = 8,076 B)

SUB 5A — TERM frame formula (FINALIZED 2026-05-01)

The TERM frame fetches the partial last chunk and the file footer. It is not a simple "goodbye" frame — its response payload contains the bytes between the last full 0x0200-aligned chunk and end_offset, and is required for reconstructing the Blastware file format.

last_chunk_counter = address of last full 0x0200-byte chunk read
next_boundary      = last_chunk_counter + 0x0200
TERM offset_word   = end_offset - next_boundary
TERM params[0]     = key[0]                 (= 0x01 on every observed device)
TERM params[1]     = key[1]                 (= 0x11)
TERM params[2]     = (next_boundary >> 8) & 0xFF
TERM params[3]     = next_boundary & 0xFF
TERM params[4:10]  = zeros
build_5a_frame(offset_word, params)         (10-byte params, NOT 11)

The device reconstructs requested_address = (params[2] << 8) | offset_word = end_offset and replies with (end_offset - next_boundary) bytes from next_boundary — the residual between the last 0x0200 boundary and the actual event end. Append the TERM response data to the chunk stream like any other A5 frame; it carries the final waveform tail + footer.

Verified across 3 events:

end_offset	last chunk	next_boundary	TERM offset_word	TERM params[2:4]
0x1ABE	0x1800	0x1A00	0x00BE ✓	1A 00 ✓
0x21F2	0x1E00	0x2000	0x01F2 ✓	20 00 ✓
0x417E	0x3E38	0x4038	0x0146 ✓	40 38 ✓

The previous code's hard-coded offset_word = 0x005A and term_counter = last + 0x0400 are wrong; the device's response under that path is a tiny 101-byte device-side terminator (arrived only after we walked the entire post-event buffer), not the proper file footer.

SUB 5A — fixed metadata pages 0x1002 and 0x1004 (NEW 2026-05-01)

Two chunk addresses are GLOBAL device/session metadata, not event-specific:

• counter=0x1002 — first metadata page
• counter=0x1004 — second metadata page

These are at fixed absolute addresses in the device's flash buffer. They contain the session-start compliance setup (Project/Client/User Name/Seis Loc/Extended Notes ASCII strings). Under the v0.14.0+ walk these strings are read directly from the metadata pages, not from the sample-chunk stream.

BW reads them ONCE per Blastware session (during event 1's download) and caches them. For SFM, that means:

• Once per call-home / once per MiniMateClient.connect() is enough.
• Subsequent events in the same session don't need to re-fetch them.
• Their content does not change when iterating events; only when the user opens Compliance Setup → Apply on the device or sends a SUB 71 compliance write.

The full byte-for-byte layout of the metadata pages has not been mapped — _decode_a5_metadata_into locates the ASCII strings via label scans (Project:, Client:, User Name:, Seis Loc:, Extended Notes) which works correctly across observed captures. Future work could dump the structural layout if more session-global fields need to be extracted.

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

bulk_waveform_params() returns 11 bytes (extra trailing 0x00). The 11th byte was confirmed from the BW wire capture. bulk_waveform_term_params() returns 10 bytes. Do not swap them.

SUB 5A — event-time metadata source (FINALIZED 2026-05-05)

The metadata strings come from the two fixed metadata pages at counter 0x1002 and 0x1004 (see "SUB 5A — fixed metadata pages 0x1002 and 0x1004" above). These pages are GLOBAL session metadata — read once per Blastware/SFM session, not per event.

"Project:"      → project description
"Client:"       → client name        ← NOT in the 0C record
"User Name:"    → operator name      ← NOT in the 0C record
"Seis Loc:"     → sensor location    ← NOT in the 0C record
"Extended Notes"→ notes

IMPORTANT — these strings are session-start config, NOT per-event: Project / Client / User Name / Seis Loc reflect the compliance setup from when the monitoring session first started, not the individual event's per-event metadata. The authoritative per-event project name is stored in the 210-byte 0C waveform record. _decode_a5_metadata_into therefore only sets project from the 5A metadata pages when 0C didn't already supply one.

"Client:", "User Name:", "Seis Loc:", and "Extended Notes" are NOT present in the 0C record — the metadata pages are the sole source for those fields and they are set unconditionally.

Deprecated knobs (do not re-introduce)

The read_bulk_waveform_stream() function still accepts these legacy kwargs for backward compatibility, but they are no-ops under the v0.14.0+ walk:

• stop_after_metadata=True — used to scan the chunk stream for b"Project:" and stop one chunk later as a workaround for the missing end_offset bound. Obsolete: the loop is now deterministically bounded by end_offset parsed from the STRT record at data[17] of the probe response, with the partial tail fetched by the TERM frame.
• extra_chunks_after_metadata — same era, same reason. No-op.

If you find code or docs referencing "A5 frame 7" as the source of metadata strings, that's an old-walk artifact (the broken 0x0400-step formula occasionally caught the 0x1002 metadata page at sample-chunk fi=7). Update to reference the dedicated metadata pages instead.

SUB 5A — end-of-stream (FINALIZED 2026-05-01)

Under the v0.14.0+ STRT-bounded walk the stream ends cleanly:

… last full chunk at counter < end_offset
TERM request   (offset_word = end_offset - next_boundary,
                params address (next_boundary))
TERM response  (page_key = 0x0000 or 0x0001, data = the residual
                end_offset - next_boundary bytes including the file footer)

No timeout-based detection, no "1-byte teaser," no max_chunks cap. The chunk loop exits when counter + 0x0200 > end_offset; the TERM frame fetches the tail.

Chunk recv timeout is 10 s, not the default 120 s. Chunks arrive within ~1 s each. Using 120 s would cause a ~2-minute stall on any unexpected timeout. The _recv_one call in the chunk loop passes timeout=10.0 explicitly.

Typical chunk count under the v0.14.0+ walk (BE11529, 1024 sps over TCP/cellular):

Event duration	Sample chunks	Metadata pages	TERM	Total A5 frames
2-sec (event 1)	~12	2	1	~15
3-sec (event 1)	13	2	1	16
2-sec (continuation)	15	0	1	16
3-sec (continuation)	~14	0	1	~15

For comparison, the deprecated 0x0400-step walk produced ~37 chunks for a 2-sec event with chunks 17-37 containing post-event circular-buffer garbage. Do not re-introduce that walk under any circumstances.

SUB 5A — fi==9 hardcoded skip (FIXED 2026-04-06)

_decode_a5_waveform() previously had elif fi == 9: continue — a leftover from the 9-frame original blast capture where frame 9 was assumed to be a terminator. Removed. TERM detection in the file builder uses frame.page_key != 0x0010 (sample marker), not frame index — see blastware_file.py.

SUB 1E / 1F — event iteration null sentinel and token position (FIXED, do not re-introduce)

token_params bug (FIXED): The token byte was at params[6] (wrong). Both 3-31-26 and 4-3-26 BW TX captures confirm it belongs at params[7] (raw: 00 00 00 00 00 00 00 fe 00 00). With the wrong position the device ignores the token and 1F returns null immediately.

1F token depends on context: In browse mode (no 5A), use all-zero params (browse=True). In download mode (get_events with 5A), use token=0xFE (browse=False) — this is required to arm the device's 5A bulk stream state machine. The earlier "empirical" test showing token=0xFE returns null was done WITHOUT the 1E(arm) step; that test is invalid. BW always uses 1F(0xFE) in download mode. count_events uses browse=True (no 5A needed).

0A context requirement: advance_event() (1F) only returns a valid next-event key when a preceding read_waveform_header() (0A) call has established device waveform context for the current key. Call 0A before every event in the loop, not just the first. Calling 1F cold (after only 1E, with no 0A) returns the null sentinel regardless of how many events are stored.

1F response layout: The next event's key IS at data_rsp.data[11:15] (= payload[16:20]). Confirmed from 4-3-26 browse-mode S3 captures:

1F after 0A(key0=01110000):  data[11:15]=0111245a  data[15:19]=00001e36  ← valid
1F after 0A(key1=0111245a):  data[11:15]=01114290  data[15:19]=00000046  ← valid
1F null sentinel:            data[11:15]=00000000  data[15:19]=00000000  ← done

Null sentinel: data8[4:8] == b"\x00\x00\x00\x00" (= data_rsp.data[15:19]) works for BOTH 1E trailing (offset to next event key) and 1F response (null key echo) — in both cases, all zeros means "no more events."

1E response layout: data_rsp.data[11:15] = event 0's actual key; data_rsp.data[15:19] = sample-count offset to the next event key (key1 = key0 + this offset). If offset == 0, there is only one event.

Correct iteration pattern (confirmed empirically with live device, 2+ events):

count_events (browse mode only, no 5A):

1E(all zeros) → key0, trailing0         ← trailing0 non-zero if event 1 exists
0A(key0)                                ← REQUIRED: establishes device context
1F(all zeros / browse=True) → key1      ← use all-zero params
0A(key1)                                ← REQUIRED before each advance
1F(all zeros) → null                    ← done

get_events (download mode, with 5A):

1E(all zeros) → key0, trailing0         ← trailing0 non-zero if event 1 exists
0A(key0)                                ← REQUIRED: establishes device context
1E(token=0xFE)                          ← REQUIRED: arms device for 5A; CONFIRMED 4-2-26 + 4-3-26
0C(key0)                                ← read waveform record
1F(token=0xFE) → [discard key]          ← REQUIRED: arms 5A bulk stream state machine
POLL × 3                                ← REQUIRED: 3 full POLL cycles before 5A (BW frames 68-73)
5A(key0)                                ← bulk stream; key0 used even though 1F already advanced
1F(all zeros / browse=True) → key1      ← USE THIS for loop iteration (browse=True returns correct key)
0A(key1)
1E(token=0xFE)                          ← re-arm for next event's 5A
0C(key1)
1F(token=0xFE) → [discard key]          ← arm 5A
POLL × 3
5A(key1)
1F(browse=True) → null                  ← done

IMPORTANT — conditional browse 1F (UPDATED 2026-04-06): 1F(token=0xFE) (browse=False) BEFORE POLL+5A arms the device's bulk stream state machine. Its returned key is cached as arm_key4 in get_events().

1F(browse=True) AFTER 5A is ONLY sent when 5A succeeded. If 5A timed out or failed, sending browse 1F disrupts the device's internal state — subsequent 5A probes for the next event get no response (confirmed empirically: calling browse 1F after a failed 5A causes the next event's 5A probe to also time out with 0 bytes received).

In the failure path, arm_key4 from 1F(download) is used as a best-effort next-key hint:

• If arm_key4 != cur_key: use it to advance the loop without any 1F call
• If arm_key4 == cur_key (device stuck, typical for second+ events when 5A fails): abort

The diagnostic bytes_fed counter on S3FrameParser (incremented in every feed() call, reset by reset()) makes it possible to distinguish "no bytes at all" from "bytes received but no complete frame assembled" in 5A probe timeouts — both show up as 120s timeouts in the log but have very different root causes.

The 1E(token=0xFE) arm step is required (FIXED 2026-04-06): The device silently ignores all 5A probe frames unless a second SUB 1E with token=0xFE has been issued between 0A and 0C. This step is present in EVERY download cycle in both the 4-2-26 and 4-3-26 BW TX captures.

1F must come BEFORE 5A (FIXED 2026-04-06): BW always calls 1F (advance event) before starting the 5A bulk stream. 5A still uses the pre-advance key — the device streams the waveform for the key that was set up with 0A+1E-arm+0C even after 1F has moved the internal pointer to the next event.

POLL × 3 required before 5A (FIXED 2026-04-06): BW sends exactly 3 complete POLL (SUB 5B) probe+data cycles between the last 1F and the first 5A probe frame. Confirmed from 4-2-26 BW TX capture frames 68-73. Without these POLLs the device does not respond to the 5A probe. Use proto.poll() (not startup() — startup() drains the boot string, which is only needed on initial connect).

advance_event(browse=True) sends all-zero params; advance_event() default (browse=False) sends token=0xFE and is NOT used by any caller. advance_event() returns (key4, event_data8). Callers (count_events, get_events) loop while data8[4:8] != b"\x00\x00\x00\x00".

SUB 0A — WAVEHDR response length distinguishes events from boundaries (NEW 2026-05-01)

When iterating events with the "Download All" pattern (1E → 0A → 1F → 0A → 1F → …), the DATA_LENGTH at data_rsp.data[5] (= the byte BW echoes back as the offset for the data fetch step) takes one of two values:

WAVEHDR offset	Meaning
0x46 (= 70)	Real event start key — there is event data at this address
0x2C (= 44)	Boundary marker between events — this key is the END of the previous event AND the START key for the empty space after it (or is the next event's pre-header)

Confirmed from the 5-1-26 "Download All" capture:

0A(key=01110000) → off=0x46    ← event 1 real start
1F → key=011121F2
0A(key=011121F2) → off=0x2C    ← event 1 END / event 2 boundary
1F → key=01112238
0A(key=01112238) → off=0x46    ← event 2 real start  (= boundary + 0x46)
1F → key=0111417E
0A(key=0111417E) → off=0x2C    ← event 2 END / next-empty marker
1F → null sentinel

This is why event 2's first 5A chunk is at start_key + 0x46 — that's the address of the "real start" 0x46-record, distinct from the 0x2C-record at the raw boundary. Use the 0x46 keys as the input to read_bulk_waveform_stream, not the 0x2C keys.

For event 1 only (start_key[2:4] = 0x0000) BW probes at counter=0x0000 directly, which is the 0x46-keyed start record. Subsequent events use start_key + 0x46.

Practical iteration pattern (replaces the old 1E/1F walk for downloads):

Setup:     SERIAL × 2 → CHCFG → 1E (token=0x00) → key0
For each event:
    0A(cur_key)           → DATA_LENGTH = 0x46 (real) or 0x2C (boundary)
    1F (token=0x00)       → next_key
    if length was 0x46:    → cur_key is a real event; queue it for download
    cur_key = next_key
    if next_key all-zero null sentinel: stop

Then for each queued real-event key:
    download_event(key)    → 5A bulk stream with STRT-bounded chunk walk

This is what BW does in the 5-1-26 "Download All" capture — it walks the full event chain collecting (key, length) tuples first, then downloads each event using the 0x46 keys.

SUB 1A — compliance config — orphaned send bug (FIXED, do not re-introduce)

read_compliance_config() sends a 4-frame sequence (A, B, C, D) where:

• Frame A is a probe (no recv_one needed — device ACKs but returns no data page)
• Frames B, C, D each need a recv_one to collect the response

There must be NO extra self._send(...) call before the B/C/D recv loop without a matching recv_one(). An orphaned send shifts all receives one step behind, leaving frame D's channel block (trigger_level_geo, alarm_level_geo, max_range_geo) unread and producing only ~1071 bytes instead of ~2126.

SUB 1A — anchor search range

_decode_compliance_config_into() locates fields via the 6-byte stable anchor b'\xbe\x80\x00\x00\x00\x00'. Search range is cfg[0:150].

IMPORTANT — the "10-byte anchor" \x01\x2c\x00\x00\xbe\x80\x00\x00\x00\x00 is NOT fully constant. The first 2 bytes (\x01\x2c = 300) are the histogram_interval_sec field (uint16 BE, seconds) — the value 300 is just the 5-minute default. When histogram interval is set to a different value (e.g. 15min = 0x0384 = \x03\x84), those bytes change. Only the 6-byte suffix \xbe\x80\x00\x00\x00\x00 is truly constant. The code already uses the 6-byte anchor.

Do not narrow the search range to cfg[40:100] — the old range was only accidentally correct because the orphaned-send bug was prepending a 44-byte spurious header, pushing the anchor from its real position (cfg[11]) into the 40–100 window.

Sample rate and DLE jitter in cfg data

Sample rate 4096 (0x1000) causes DLE jitter: the frame carries 10 10 00 on the wire, which unstuffs to 10 00 — 2 bytes instead of 3. This makes frame C 1 byte shorter and shifts all subsequent absolute offsets by −1. The anchor approach is immune to this. Do NOT use fixed absolute offsets for sample_rate or record_time.

TCP / cellular transport

• Protocol bytes over TCP are bit-for-bit identical to RS-232. No wrapping.
• The modem (RV50/RV55) forwards bytes with up to ~1s buffering. TcpTransport uses read_until_idle(idle_gap=1.5s) to drain the buffer completely before parsing.
• Cold-boot: unit sends the 16-byte ASCII string "Operating System" before entering DLE-framed mode. The parser discards it (scans for DLE+STX).
• RV50/RV55 sends \r\nRING\r\n\r\nCONNECT\r\n over TCP to the caller even with Quiet Mode enabled. Parser handles this — do not strip it manually before feeding to S3FrameParser.

Required ACEmanager settings (Sierra Wireless RV50/RV55)

Setting	Value	Why
Configure Serial Port	38400,8N1	Must match MiniMate baud
Flow Control	None	Hardware FC blocks TX if pins unconnected
Quiet Mode	Enable	Critical. Disabled injects RING/CONNECT onto serial, corrupting S3 handshake
Data Forwarding Timeout	1 (= 0.1 s)	Lower latency
TCP Connect Response Delay	0	Non-zero silently drops first POLL frame
TCP Idle Timeout	2 (minutes)	Prevents premature disconnect
DB9 Serial Echo	Disable	Echo corrupts the data stream

---

Key confirmed field locations

SUB FE — Full Config (166 destuffed bytes)

Offset	Field	Type	Notes
0x34	firmware version string	ASCII	e.g. "S338.17"
0x56–0x57	calibration year	uint16 BE	0x07E9 = 2025
0x0109	aux trigger enabled	uint8	0x00 = off, 0x01 = on

SUB 1A — Compliance Config (~2126 bytes total after 4-frame sequence)

Field	How to find it
recording_mode	uint8 at anchor − 3 (write) / anchor − 4 (read) ✅ confirmed 2026-04-20
sample_rate	uint16 BE at anchor − 2
histogram_interval_sec	uint16 BE at anchor − 4 (seconds); same offset in read & write ✅ confirmed 2026-04-20
record_time	float32 BE at anchor + 10
trigger_level_geo	float32 BE, located in channel block
alarm_level_geo	float32 BE, adjacent to trigger_level_geo
geo_hardware_constant (adc_scale_factor)	float32 BE at channel_label+28 in both read (E5) and write (SUB 71) payloads — reads 6.206053 on BOTH tested units (BE11529 and BE18189); identical across all geo channels (Tran/Vert/Long) and all captures. Confirmed 2026-04-17 from Interface Handbook §4.5: this is the ADC-to-velocity scale factor = 1/sensitivity = (in/s per V). Firmware uses it as: PPV (in/s) = ADC_voltage × 6.206053. Cross-check: 1.61133 V (ADC full-scale) × 6.206053 = 10.000 in/s (Normal range ✅). Do NOT write this field — it is a hardware/firmware constant.
geo_range (sensitivity selector)	uint8 at channel_label+33 in both read (E5) and write (SUB 71) payloads — CONFIRMED 2026-04-20 from 4-20-26 geo sensitivity captures: 0x00 = Normal 10.000 in/s (standard gain), 0x01 = Sensitive 1.250 in/s (high gain). Present in all three geo channel blocks (Tran, Vert, Long). NOTE: channel_label+20 reads 0x01 on ALL captures regardless of range setting — it is NOT this field. Note: the "SUB 71 write offset = +29" that appears in earlier analysis was an artifact of incorrect BW-style destuffing applied to write frame data — write frame data is RAW, so the literal 0x10 bytes in the channel block header are preserved, and the offset is the same as in the E5 read payload.
setup_name	ASCII, null-padded, in cfg body
project / client / operator / sensor_location	ASCII, label-value pairs

True stable anchor: b'\xbe\x80\x00\x00\x00\x00' (6-byte suffix), search cfg[0:150]. The old "10-byte anchor" b'\x01\x2c\x00\x00\xbe\x80\x00\x00\x00\x00' is partially variable: bytes \x01\x2c = 300 (5-minute default histogram interval); changes when interval changes.

Field layout relative to the 6-byte anchor (write payload / E5 read — noted where different):

Offset	Field	Format	Notes
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
anchor	\xbe\x80\x00\x00\x00\x00	anchor
anchor + 6	record_time	float32 BE	same in read & write

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

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)

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])

sub_code=0x10 (Waveform single-shot) — 9-byte timestamp header:

Offset	Field	Type
0	day	uint8
1	sub_code	uint8 (0x10)
2	month	uint8
3–4	year	uint16 BE
5	unknown	uint8 (always 0)
6	hour	uint8
7	minute	uint8
8	second	uint8

sub_code=0x03 (Waveform continuous) — 10-byte timestamp header (1-byte shift):

Confirmed 2026-04-03 against Blastware event report (15:20:17 Apr 3 2026). Raw wire bytes: 10 03 10 04 07 ea 00 0f 14 11

Offset	Field	Type	Notes
0	unknown_a	uint8	0x10 observed
1	day	uint8	doubles as sub_code position in 0x10 layout
2	unknown_b	uint8	0x10 observed
3	month	uint8
4–5	year	uint16 BE
6	unknown	uint8
7	hour	uint8
8	minute	uint8
9	second	uint8

Peak values (both record types):

Location	Field	Type
tran_pos - 12	peak_vector_sum	float32 BE — label-relative, NOT fixed offset
label + 6	PPV per channel	float32 BE (search for "Tran", "Vert", "Long", "MicL")

PPV labels are NOT 4-byte aligned. The label-relative approach is the only reliable method. peak_vector_sum is exactly 12 bytes before the "Tran" label — confirmed for both sub_code=0x10 and sub_code=0x03. Do NOT use fixed offset 87 (only incidentally correct for 0x10 records).

---

SFM REST API (sfm/server.py)

Live device endpoints (connect to device per-request)

GET  /device/info?port=COM5                              ← serial
GET  /device/info?host=1.2.3.4&tcp_port=9034            ← cellular
GET  /device/events?host=1.2.3.4&tcp_port=9034&baud=38400
GET  /device/event?host=1.2.3.4&tcp_port=9034&index=0
GET  /device/monitor/status?host=1.2.3.4&tcp_port=9034  ← battery, memory, mode
POST /device/monitor/start?host=1.2.3.4&tcp_port=9034   ← start recording
POST /device/monitor/stop?host=1.2.3.4&tcp_port=9034    ← stop recording

Server retries once on ProtocolError for TCP connections (handles cold-boot timing).

DB read endpoints (query seismo_relay.db written by ach_server.py)

GET  /db/units                                           ← all known serials + summary stats
GET  /db/events?serial=BE11529&from_dt=&to_dt=&limit=   ← triggered events, newest first
GET  /db/monitor_log?serial=BE11529&from_dt=&to_dt=     ← monitoring intervals, newest first
GET  /db/sessions?serial=BE11529&limit=50               ← ACH call-home sessions, newest first
PATCH /db/events/{id}/false_trigger?value=true          ← flag/unflag false triggers

DB file: bridges/captures/seismo_relay.db (default; override with --db-path at startup). All DB endpoints are read-only except PATCH /db/events/{id}/false_trigger.

---

Key wire captures (reference material)

Capture	Location	Contents
1-2-26	bridges/captures/1-2-26/	SUB 5A BW TX frames — confirmed 5A frame format, 11-byte params, DLE-aware checksum
3-11-26	bridges/captures/3-11-26/	Full compliance setup write, Aux Trigger capture
3-31-26	bridges/captures/3-31-26/	Complete event download cycle (148 BW / 147 S3 frames) — confirmed 1E/0A/0C/1F sequence; only 1 event stored so token=0xFE appeared to work
4-3-26	bridges/captures/4-3-26/	Browse-mode S3 capture with 2+ events — confirmed all-zero params for 1F, 1F response layout, null sentinel, 0A context requirement
4-27-26	bridges/captures/4-27-26/	BW "open 2sec waveform" + "copy event to disk" + paired SFM "seismo_dl" — first proof that SFM was over-reading 5× past event end. BW reads 14 chunks at 0x0200 increments + TERM at end_offset; SFM was reading 37 chunks at 0x0400 increments. STRT end_key field located.
5-1-26	bridges/captures/5-1-26/comcheck/	Three sub-captures: SFM 3-sec download (seismo_dl_…), BW comms-check + 3-sec download (bwcap3sec/), BW second-event download + "Download All" (raw_*_170945/_171216). Confirmed: TERM frame formula across 3 events; metadata pages 0x1002/0x1004 are global (read once per session); event-1 vs event-N chunk-pattern split; WAVEHDR length 0x46 vs 0x2C disambiguates real events from boundaries.

---

Write commands (SUBs 68–83) — confirmed 2026-04-07

All confirmed from 3-11-26 BW TX capture (raw_bw_20260311_170151.bin, frames 102–112).

Write frame format — CRITICAL: minimal DLE stuffing

Write frames do NOT use the same DLE stuffing as read frames. Only the BW_CMD byte (0x10 at payload position [0]) is doubled on the wire. All other bytes — flags, sub, offset, params, data, and checksum — are written RAW without stuffing.

Confirmed from all 11 write frames in the 3-11-26/170151 BW capture. ✅ 2026-04-07

Do NOT use dle_stuff() or build_bw_frame() for write commands. Use build_bw_write_frame().

Actual wire layout:
  [41]       ACK
  [02]       STX
  [10 10]    BW_CMD doubled (ONLY DLE stuffing applied)
  [00]       flags
  [sub]      write command byte (0x68–0x83)
  [00]       always zero
  [hi][lo]   offset uint16 BE — RAW (not stuffed even if hi=0x10)
  [params]   10 bytes — RAW
  [data]     variable-length write payload — RAW (0x10 bytes not stuffed)
  [chk]      checksum — RAW (not stuffed even if 0x10)
  [03]       ETX

Total wire length = 2 (ACK+STX) + 2 (doubled BW_CMD) + 15 (raw header) + len(data) + 1 (chk) + 1 (ETX)
                 = 21 + len(data)

De-stuffed payload (logical; used for checksum computation only):

  [0]     BW_CMD  0x10
  [1]     flags   0x00
  [2]     SUB     write command byte (0x68–0x83)
  [3]     0x00    always zero
  [4]     offset_hi
  [5]     offset_lo
  [6:16]  params  10-byte field (see per-SUB notes below)
  [16:]   data    write payload (variable length; absent for confirm frames)
  [-1]    chk     large-frame DLE-aware checksum (see below)

Write SUBs = Read SUB + 0x60. Response SUB follows the standard 0xFF − Request SUB rule.

Write frame checksum

All write frames (data frames AND confirm frames) use the large-frame DLE-aware checksum:

chk = (sum(b for b in payload[2:] if b != 0x10) + 0x10) & 0xFF

This is identical to the SUB 5A DLE-aware checksum. Confirmed against all 11 write frames in the 3-11-26/170151 capture. ✅ 2026-04-07

Note: confirm frames contain no embedded 0x10 bytes, so both the standard SUM8 and the DLE-aware formula produce the same result for them — but build_bw_write_frame always uses the DLE-aware formula for consistency.

Write ack responses

All device acks for write commands are 17-byte zero-data S3 frames:

[DLE=0x10][STX=0x02][stuffed(header + chk)][bare ETX=0x03]

The data section carries zeros; RSP_SUB = 0xFF − write_request_SUB.

Write SUB constants and sequences

Request SUB	Function	Offset	Response SUB
0x68	Event index write	data[1] + 2	0x97
0x73	Confirm B (follows 68)	0	0x8C
0x71	Compliance write (×3 chunks)	see below	0x8E
0x72	Confirm A (follows 71×3, 69)	0	0x8D
0x82	Trigger config write	data[1] + 2	0x7D
0x83	Trigger confirm (follows 82)	0	0x7C
0x69	Waveform data write	data[1] + 2	0x96
0x74	Confirm C (follows 69)	0	0x8B

Offset formula for single-chunk writes (0x68, 0x69, 0x82): offset = data[1] + 2

The write payload always begins with a 2-byte header [0x00][length], where data[1] is an embedded length field. The offset encodes this inner length + 2 (accounting for the header bytes). Confirmed from all three single-chunk write frames in the 3-11-26 capture:

SUB	data[0:4] (hex)	data[1]	offset	total data len
0x68	00 58 09 00	0x58=88	0x5A=90	91
0x82	00 1A D5 00	0x1A=26	0x1C=28	29
0x69	00 C8 08 00	0xC8=200	0xCA=202	204

Full sequence: 68→73 | 71×3→72 | 82→83 | 69→74→72

SUB 71 — compliance write chunk parameters

The full compliance config payload (~2128 bytes) is split into exactly 3 chunks. Confirmed from 3-11-26 BW TX capture frames 104–108:

Chunk	Size	offset	params (10 bytes hex)
1 (first)	1027 bytes	0x1004	00 00 00 00 00 00 00 00 00 00
2 (middle)	1055 bytes	0x1004	00 00 00 10 04 00 00 00 00 00
3 (last)	remainder	0x002C	00 00 08 00 00 00 00 00 00 00

Total: 1027 + 1055 + N = 2082 + N bytes (N ≈ 46 for a standard 2128-byte config).

After all 3 chunks are acked (SUB 0x8E each), send SUB 72 confirm → device acks 0x8D.

build_bw_write_frame() — framing.py

build_bw_write_frame(sub, data, *, offset=0, params=bytes(10)) -> bytes

Use for all write commands (SUBs 68–83) including confirm frames (data=b""). Do NOT use build_bw_frame for write commands — it uses standard SUM8, not the large-frame DLE-aware checksum required for writes.

push_config_raw() — client.py

client.push_config_raw(event_index_data, compliance_data, trigger_data, waveform_data)

Orchestrates the full write sequence in the confirmed order. All payloads are raw bytes (no encoding performed at this level). A higher-level encoder that builds payloads from a ComplianceConfig object is a future task.

---

Monitoring commands (SUBs 0x1C, 0x96, 0x97) — confirmed 2026-04-08

All confirmed from 4-8-26/2ndtry BW TX/S3 capture (clean start → 30s monitor → stop cycle).

SUB 0x1C — Monitor status read

Standard two-step read (probe at offset 0x00, data at offset 0x2C). Response SUB = 0xFF − 0x1C = 0xE3 (standard formula — no exception).

Payload length is 46–47 bytes IDLE, 48–49 bytes MONITORING — not a reliable sole indicator due to 1-byte jitter overlap at the boundary.

Monitoring flag (CONFIRMED 2026-04-09 — byte diff of all 144 data frames, 2ndtry capture):

• section[1] == 0x00 → unit is idle
• section[1] == 0x10 → unit is monitoring

This is data[12] (= frame.data[12]). The flag is 0x00 in all 36 IDLE_BEFORE frames, 0x10 in all 98 MONITORING frames, and 0x00 in all 10 IDLE_AFTER frames — 100% accurate.

HISTORY OF THIS FIELD (do not re-derive): The original implementation used section[1]. A re-analysis in the prior session incorrectly concluded section[1] is always 0x00 and "corrected" the flag to section[6], which has non-binary values (0xea idle, 0x07 monitoring) and is device-specific. The 2026-04-09 re-analysis confirms section[1] was right.

IMPORTANT — frame.data has checksum already stripped by S3FrameParser._finalise() (raw_payload = body[:-1]; data = raw_payload[5:]). There is NO trailing checksum byte in section. All relative-from-end offsets must account for this.

Battery and memory fields are present in both states:

Offset (relative to end)	Field	Type	Notes
section[-10:-8]	battery voltage × 100	uint16 BE	0x02A8 = 680 → 6.80 V
section[-8:-4]	memory total (bytes)	uint32 BE	e.g. 983026 ≈ 960 KB
section[-4:]	memory free (bytes)	uint32 BE	decreases as events are stored

SESSION_RESET signal (41 03) — required for monitoring units

Confirmed from 4-8-26 BW TX captures: Blastware sends a 2-byte 41 03 (ACK + ETX, no STX) immediately before the first POLL probe AND between the probe and data frames. This signal is required to wake units that are actively monitoring — without it the unit does not respond to POLL over TCP. Harmless for idle units.

SESSION_RESET = bytes([0x41, 0x03]) is defined in framing.py and sent by protocol.startup() before and between POLL frames.

SUB 0x96 — Start monitoring

Single write frame, no data payload (empty body). Response SUB = 0xFF − 0x96 = 0x69.

Wire bytes (confirmed frame 92 of 2ndtry BW capture):

41 02 10 10 00 96 00 00 00 00 00 00 00 00 00 00 00 00 00 a6 03

SUB 0x97 — Stop monitoring

Single write frame, no data payload (empty body). Response SUB = 0xFF − 0x97 = 0x68.

Wire bytes (confirmed frame 305 of 2ndtry BW capture):

41 02 10 10 00 97 00 00 00 00 00 00 00 00 00 00 00 00 00 a7 03

Both start and stop acks are standard 17-byte zero-data S3 frames.

On-device sensor check behavior (confirmed 2026-04-08)

Confirmed from 4-8-26/sensor-check BW+S3 capture (Blastware "Unit Channel Test" comms check issued while unit was performing its on-device sensor check).

Unit IS reachable during on-device sensor check — POLL (SUB 5B) responded normally throughout. However, the unit partially handled channel-test commands (SUB 0x0E) for channels 0–4 and then went silent for ~40 seconds while the sensor check ran, before resuming responses for channels 5–7 and the trigger test (SUB 0x98).

Key findings:

• On-device sensor check duration: approximately 40 seconds (log gap 18:40:48 → 18:41:28)
• Unit IS reachable for POLL during the check window — SESSION_RESET + POLL works
• Partial command responses during check are possible (device may buffer some, drop others)
• The Blastware "Unit Channel Test" (remote comms check, SUBs 0x0E + 0x98) is a SEPARATE operation from the on-device check — it is a passive remote read; the unit's screen does not change during a remote comms check

SFM behavior after POST /device/monitor/start: _pollMonitorConfirm() polls /device/monitor/status every 5 s for up to 60 s, updating the badge on each poll. Status will show MONITORING once section[1] flips to 0x10.

SUBs known from sensor-check capture (4-8-26) — NOT YET IMPLEMENTED

BW SUB	RSP SUB	Function	Notes
0x15	0xEA	Serial number / short ID	2-step read; data offset = 0x0A (10 bytes); confirmed serial "BE11529" at data[11+5:]
0x01	0xFE	Device info block	2-step read; data offset = 0x98 (152 bytes); payload includes serial + firmware + float config fields
0x0E	0xF1	Channel sensor data	2-step read; channel selector in params[6:8] (0x0000–0x0007); data length 0x0A per channel; used by Blastware "Unit Channel Test" — see docs/ for details
0x98	0x67	Trigger test	Single probe frame (params[0]=0xFF); sent twice per test cycle; all-zero data response; used after 0x0E channel scan

Blastware's "Unit Channel Test" sequence: POLL×N → 0x15 → 0x01 → 0x08 → 0x01 → 0x0E×8 → 0x98×2 → 0x0E×8 (repeat pass with live ADC readings).

---

Compliance config field inventory (from Blastware UI, 2026-04-08)

Fields visible in the Blastware Compliance Setup dialog — most are NOT YET decoded to byte offsets in the raw 1A/E5 payload. Only fields with ✅ have confirmed offsets in the code.

Recording Setup tab:

• Recording Mode: Continuous / Single Shot / Histogram / Histogram+Continuous ✅ (uint8 at anchor−3 in write, anchor−4 in read; 0x00=Single Shot, 0x01=Continuous, 0x03=Histogram, 0x04=Histogram+Continuous) — confirmed 2026-04-20
• Record Stop Mode: Fixed Record Time / Auto / Manual Stop (enum) ❓ (byte near recording_mode; data[40] in E5 sf1 changed 0x01→0x00 alongside Continuous→Single Shot — may be this field)
• Sample Rate: Standard 1024 / Fast 2048 / Faster 4096 sps ✅ (anchor−2)
• Record Time: float, seconds ✅ (anchor+10)
• Histogram Interval: 2s / 5s / 15s / 1m / 5m / 15m ✅ (uint16 BE seconds at anchor−4, same in read & write; mode-gated to Histogram/Histogram+Continuous) — confirmed 2026-04-20
• Storage Mode: Save All Data / Save Triggered (enum)
• Geophone Type: Standard Triaxial / 4.5 Hz (bool/enum)
• Geophone Channels: Enable all geophones (bool), Trigger Source (bool)
• Chan 1-3 Trigger Level (float, in/s) ✅ (trigger_level_geo)
• Chan 1-3 Maximum Range: Normal 10.000 / 1.25 in/s (enum) ✅ (geo_range uint8; CONFIRMED 2026-04-20 from 4-20-26 geo sensitivity captures: offset = channel_label+33 in both E5 read and SUB 71 write payloads (same bytes, round-tripped verbatim); 0x00 = Normal 10.000 in/s, 0x01 = Sensitive 1.250 in/s; applied to Tran/Vert/Long channel blocks). IMPORTANT: channel_label+20 reads 0x01 on ALL captures and is NOT this field — it is a constant flag. The float32 at channel_label+28 = 6.206053 is the ADC-to-velocity scale factor (hardware constant, do NOT write).
• Microphone Channels: Enable all microphones (bool), Trigger Source (bool)
• Chan 4 Trigger Level (dB or psi depending on units)

Notes tab:

• Enable User Notes (bool)
• Project, Client, User Name, Seis Loc (ASCII strings) ✅ (sourced from 5A metadata pages at counter 0x1002 / 0x1004 — see "SUB 5A — fixed metadata pages" section)
• Enable Extended Notes (bool); Extended Notes text; Extended Notes Title
• Enable Job Number (bool); Job Number (int)
• Enable Scaled Distance (bool); Distance from Blast (float); Charge Weight (float) — Scaled Distance is derived

Special Setups tab:

• Unit Timer: Timer Mode (Off/On), Start Date/Time, Stop Date/Time
• Self Check: Mode (Off/On), Time (HH:MM)
• Sensor Check: Before monitoring / After each event / Disabled ❓ (byte offset unknown)
• Measurement Units: Imperial / Metric
• Show Mic units in dB (bool)
• Time Format: 24 Hour / 12 Hour (AM/PM)
• Backlight on Time (seconds) ✅ (event index block +75)
• Power Saving Timeout (minutes) ✅ (event index block +83)
• Monitoring LCD Cycle ✅ (event index block +84:86)
• Set unit time with setup (bool)

The "Sensor Check" dropdown (Before monitoring / After each event / Disabled) has NOT been located in the raw config bytes. The user's unit always runs with Before monitoring. Full compliance config encoder is a future task.

---

---

Erase-all protocol (SUBs 0xA3/0xA2/0x06) — confirmed 2026-04-11

Full sequence confirmed from 4-11-26 MITM capture of a live Blastware ACH session (bridges/captures/mitm/ach_mitm_20260411_001912/).

Wire sequence

BW → device:  SUB 0xA3  params=00 00 00 00 00 00 00 FE 00 00  (begin erase)
device → BW:  SUB 0x5C  (ack)
BW → device:  SUB 0x1C  probe (offset=0x00)
device → BW:  SUB 0xE3  (probe ack)
BW → device:  SUB 0x1C  data  (offset=0x2C)
device → BW:  SUB 0xE3  (monitor status response)
BW → device:  SUB 0x06  probe (offset=0x00, params same)
device → BW:  SUB 0xF9  (probe ack)
BW → device:  SUB 0x06  data  (offset=0x24)
device → BW:  SUB 0xF9  (36-byte storage range response)
BW → device:  SUB 0xA2  params=00 00 00 00 00 00 00 FE 00 00  (confirm erase)
device → BW:  SUB 0x5D  (ack — device memory is now cleared)

All frames use standard build_bw_frame (not write-format). Response SUBs follow the standard 0xFF - SUB formula; no exceptions.

SUB 0x06 — event storage range response (36 bytes)

The 36-byte response body ends with two 4-byte event keys:

Offset (from end)	Field	Notes
[-8:-4]	first stored event key	01110000 when empty
[-4:]	last stored event key	01110000 when empty

Before erase: ends with <first_key> <last_key> (e.g. 0111ea60 0111eaa6). After erase: both bytes read 01110000 — device's empty/reset sentinel.

Post-erase key counter reset

After a successful erase, the device resets its event counter. New events start from key 0x01110000 again — the same key as the very first event ever recorded. This means key-based deduplication in the ACH server must account for key reuse:

• After our own erase: ach_state.json downloaded_keys and max_downloaded_key are cleared so the next session starts fresh.
• After an external erase: the ACH server detects it by comparing max(device_keys) to max_downloaded_key from state. If the device max has rolled back below the historical max, all current device keys are treated as new regardless of seen_keys.

ACH server state format (v0.9.0)

bridges/captures/ach_state.json:

{
  "BE11529": {
    "downloaded_keys":    ["01110000", "0111245a"],
    "max_downloaded_key": "0111245a",
    "last_seen":          "2026-04-11T01:04:36",
    "serial":             "BE11529",
    "peer":               "63.43.212.232:51920"
  }
}

max_downloaded_key is the high-water mark — the largest key ever downloaded from the unit. It is NOT reset when events are erased from the device (only when our server does the erase). Used for post-erase detection.

---

Monitor log entries — SUB 0x0A partial records (confirmed 2026-04-11)

Confirmed from 4-11-26 MITM capture: 12 partial records (record type 0x2C) and 7 full event records (record type 0x46) across 19 total 0x0A responses.

Record type detection

read_waveform_header() returns (raw_data, length) where raw_data = data_rsp.data (the full payload including prefix bytes). The record type is at raw_data[0]:

Value	Type	How to process
0x46	Full triggered event	Normal download: 0C → 5A → 1F
0x2C	Monitor log entry (partial)	No 0C/5A; decode inline from 0A payload

Length heuristic: length < 0x40 (64) reliably identifies partial records across all observed captures. Both checks (raw_data[0] == 0x2C and length < 0x40) are used.

SUB 0x0A partial record (0x2C) payload layout

All offsets are from raw_data (the full data_rsp.data array including the 11-byte prefix before the actual header bytes start).

raw_data[0]   = 0x2C   ← record type (partial / monitor log)
raw_data[1:11] = prefix bytes (vary; contain key4 copy, flags, length)
raw_data[11:] = timestamp and ASCII metadata payload

Timestamp auto-detection (confirmed from 4-11-26 capture):

raw_data[11] == 0x10  →  10-byte sub_code=0x03 format (continuous mode)
raw_data[11] != 0x10  →  9-byte sub_code=0x10 format (single-shot mode)

9-byte timestamp format (sub_code=0x10):

Byte	Field
0	day
1	0x10 (sub_code marker)
2	month
3–4	year (uint16 BE)
5	unknown (0x00)
6	hour
7	minute
8	second

10-byte timestamp format (sub_code=0x03):

Byte	Field
0	0x10 (marker)
1	day
2	0x10 (marker)
3	month
4–5	year (uint16 BE)
6	unknown (0x00)
7	hour
8	minute
9	second

Two timestamps: Each partial record contains two timestamps — start_time and stop_time — stored consecutively:

• ts1 (start) at raw_data[ts_offset : ts_offset + ts_size] where ts_offset = 11
• ts2 (stop) at raw_data[ts1_end : ts1_end + ts_size]

Edge case — 1-byte gap between timestamps: Occurs when ts1 and ts2 share the same minute:second. If try_ts(raw_data[ts1_end:]) fails, try try_ts(raw_data[ts1_end+1:]). Confirmed in frames 121, 161, 165 of the 4-11-26 MITM capture. Frame 121 still shows 0s duration (both decode to 16:02:00) — the extra byte appears in all same-second cases.

ASCII metadata after timestamps:

<separator bytes>  BE<serial>\x00Geo: <float> in/s ...

• Serial: scan for b"BE", read until b"\x00" (e.g. "BE11529")
• Geo threshold: scan for b"Geo: ", read float until next space (e.g. 0.254 in/s)

A separator of variable length (4–5 bytes of \x00 + flags) sits between the two timestamps and the ASCII region. The b"BE" anchor scan is robust to separator length variation.

_decode_0a_partial_header(raw_data, index, key4) — client.py

Returns a MonitorLogEntry or None. Called by get_monitor_log_entries() for each event key whose 0x0A response has raw_data[0] == 0x2C or length < 0x40.

MiniMateClient.get_monitor_log_entries(skip_keys=None) — client.py

Browse-mode walk: 1E → 0A → check type → decode if partial → 1F. No 0x0C or 5A reads performed. Full (0x46) records are skipped without decoding. Returns list[MonitorLogEntry].

skip_keys (optional set[str]): keys in this set are still advanced through the walk (to avoid disrupting the iteration sequence), but no MonitorLogEntry is created for them.

MonitorLogEntry model — models.py

@dataclass
class MonitorLogEntry:
    index: int                                      # 0-based position
    key: str                                        # 8-hex event key
    start_time: Optional[datetime.datetime] = None
    stop_time:  Optional[datetime.datetime] = None
    serial: Optional[str] = None
    geo_threshold_ips: Optional[float] = None
    raw_header: Optional[bytes] = field(default=None, repr=False)

    @property
    def duration_seconds(self) -> Optional[float]: ...

ACH server integration (v0.10.0)

After get_events(), the ACH server calls get_monitor_log_entries(skip_keys=seen_keys). New entries are saved to monitor_log.json in the session directory. Monitor log keys are included in current_keys for state persistence so they are not re-processed on the next 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

@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

See README.md → Roadmap (Future) for the canonical deferred-work list. This section is kept as a status log of in-progress / recently-shipped technical details (encoding schemes, byte layouts, etc.) that are too low-level for the README's roadmap.

• 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 BYTE-PERFECT against BW reference (v0.14.3, 2026-05-05): when fed the BW 5-1-26 3-sec capture's A5 frames, the SFM-built file matches BW's saved M529LKIQ.G10 byte-for-byte (8708 bytes, 0 differences). Live SFM downloads of event 0 (3-sec) and event 1 (3-sec continuation) both open cleanly in Blastware with full Event Reports, frequency analysis, and waveform plots. Body assembly is just contiguous concatenation of frame contributions in stream order (probe → meta@0x1002 → meta@0x1004 → samples → TERM); no stripping, no overlay, no special handling. Histogram+Continuous mode deferred (5A stream for those events embeds histogram interval records that may need different handling — untested under v0.14.x). Extension mapping: 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)

BW capture reference

bridges/captures/ contains the following BW TX + S3 response captures for protocol analysis:

Folder / File	Contents
1-2-26/	First SUB 5A BW TX capture — established 5A frame format (raw offset_hi, DLE-aware checksum). 10 frames verified.
3-11-26/raw_bw_20260311_170151.bin	Full compliance write + event download (SUBs 68→83 confirmed, frames 102–112)
3-31-26/	Single-event download (148 BW / 147 S3 frames) — 1E/0A/0C/1F sequence confirmed (single event so token=0xFE appeared to work in either branch)
4-2-26/	Download-mode BW TX capture — POLL×3 requirement confirmed (frames 68-73 between 1F and first 5A)
4-3-26-multi_event/	Browse-mode S3 capture with 2+ events — all-zero params for 1F, null sentinel layout, 0A context requirement
4-8-26/	Monitor status read, start/stop monitoring, SESSION_RESET signal, sensor check
4-11-26 (mitm/ach_mitm_20260411_001912/)	Full ACH call-home MITM — erase protocol (0xA3/0x06/0xA2), monitor log partial records confirmed
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
4-27-26/	BW "open 2sec waveform" + "copy event to disk" + paired SFM "seismo_dl" — first proof of 5× SFM over-read. STRT end_key field located.
5-1-26/comcheck/	Triplet of captures that nailed the v0.14.0 walk: SFM 3-sec download (seismo_dl_…), BW comms-check + 3-sec download (bwcap3sec/), BW second-event download + "Download All" (raw_*_170945 / _171216). Confirmed: TERM frame formula across 3 events, metadata pages 0x1002/0x1004 are global session metadata, event-1 vs event-N chunk pattern split, WAVEHDR off=0x46 vs 0x2C disambiguates real events from boundaries.
5-1-26/comcheck/bwcap3sec/	The byte-perfect reference for v0.14.3. All 17 BW 5A request frames (probe, 2 metadata, 13 samples, TERM) reproduce byte-for-byte from SFM's framing helpers — including the 10 10 00 DLE-stuffed counter for sample @ 0x1000 that was the long-standing failure mode.
5-4-26/	BW MITM captures of "copy 3sec / 2sec / Download All" + paired SFM session (seismo_dl_20260504_145701) showing the +0x46 event-N probe bug producing 110-chunk runaway walk. Cross-references against 5-1-26 confirmed device behavior is identical.

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).�������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������