18 KiB
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: v0.7.0.
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, …
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
Current implementation state (v0.7.0)
Full read pipeline 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) | 5A | ✅ new v0.6.0 |
| Event advance / next key | 1F | ✅ |
| Write commands (push config to device) | 68–83 | ❌ not yet implemented |
get_events() sequence per event: 1E → 0A → 0C → 5A → 1F
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
0x10byte 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+ETXas inner terminators. The outer parser treatsDLE+ETXinside a frame as literal data — the bare ETX is the ONLY real frame terminator. - Response SUB rule:
response_SUB = 0xFF - request_SUB(one known exception: SUB1C→ response6E, not0xE3) - 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
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:
-
offset_hi = 0x10must NOT be DLE-stuffed. Blastware sends the offset field raw.build_bw_framewould stuff it to10 10on the wire — the device silently ignores the frame.build_5a_framewrites it as a bare10. -
DLE-aware checksum. When computing the checksum,
10 XXpairs in the stuffed section contribute onlyXXto the running sum; lone bytes contribute normally. This differs from the standard SUM8-of-destuffed-payload that all other commands use.
Both differences confirmed by reproducing Blastware's exact wire bytes from the 1-2-26 BW TX capture. All 10 frames verified.
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 lives in A5 frame 7
The bulk stream sends 9+ A5 response frames. Frame 7 (0-indexed) contains the compliance setup as it existed when the event was recorded:
"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 — 5A "Project:" is session-start config, NOT per-event (confirmed 2026-04-05):
The "Project:" string in the A5 frame 7 payload reflects the compliance setup from when
the monitoring session first started, not the individual event's project name. The per-
event project name is correctly stored in the 210-byte 0C waveform record and must be
used as the authoritative source. _decode_a5_metadata_into therefore only sets
project from 5A when 0C didn't already supply one.
"Client:", "User Name:", "Seis Loc:", and "Extended Notes" are NOT present in the 0C record — 5A remains the sole source for those fields and they are set unconditionally.
stop_after_metadata=True (default) stops the 5A loop as soon as b"Project:" appears,
then sends the termination frame.
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 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_oneneeded — device ACKs but returns no data page) - Frames B, C, D each need a
recv_oneto 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 sample_rate and record_time via the anchor
b'\x01\x2c\x00\x00\xbe\x80\x00\x00\x00\x00'. Search range is cfg[0:150].
Do not narrow this 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.
TcpTransportusesread_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\nover TCP to the caller even with Quiet Mode enabled. Parser handles this — do not strip it manually before feeding toS3FrameParser.
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 |
|---|---|
| sample_rate | uint16 BE at anchor − 2 |
| 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 |
| max_range_geo | float32 BE, adjacent to alarm_level_geo |
| setup_name | ASCII, null-padded, in cfg body |
| project / client / operator / sensor_location | ASCII, label-value pairs |
Anchor: b'\x01\x2c\x00\x00\xbe\x80\x00\x00\x00\x00', search cfg[0:150]
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)
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
Server retries once on ProtocolError for TCP connections (handles cold-boot timing).
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 |
What's next
- Write commands (SUBs 68–83) — push compliance config, channel config, trigger settings to device
- ACH inbound server — accept call-home connections from field units
- Modem manager — push RV50/RV55 configs via Sierra Wireless API