Thor pushed a setup named TEST1.mmb to UM12947 while seismo_lab's TCP bridge
recorded both directions. We still have not originated a write frame -- the
wire format is now known, our encoder is not written.
Topology worth reusing: socat shares /dev/ttyACM0 on TCP from mint-mac,
seismo_lab relays Thor to it. Thor is pointed at 127.0.0.1 as if the unit were
a field modem. No modem, no SIM, production Thor box untouched.
The sequence is Series III's, plus one command:
Thor: 5B | 41 | 08 | 2E | 1A | DA | 68->73 | 82->83 | 71->72
unit: A4 | BE | F7 | D1 | E5 | 25 | 97 8C | 7D 7C | 8E 8D
All 12 device responses checksum-validate and every write is acked. Every
write response SUB matches the Series III table exactly.
New:
* SUB 0xDA names the target .MMB file -- 256 bytes, filename null-padded,
nothing else. This is why no generic file-transfer command exists: Thor
names the file, then writes the ordinary config block into it.
* SUB 0x41 reads the active setup's filename; SUB 0x2E reads trigger config.
* Reads are single-step -- Thor asks offset=0xFFFF and skips the probe.
* 0x71 writes the whole 2090-byte block in ONE frame, not Series III's three
chunks. 0x69/0x74 are absent.
Write-frame destuffing is `10 XX` -> `XX` uniformly, including `10 03`. Chosen
by checksum, not assumption: of four candidate rules, only this one makes all
four data-carrying write frames validate. 0x71's data holds 4 literal 0x03
bytes escaped as `10 03`, so escaping is mandatory for any writer.
The write body IS the read body -- 0x71 and the 0xE5 response align at a fixed
11-byte shift with 1902/2090 bytes equal (91.0%). Setups are read-modify-write.
The 12 differing regions are fully mapped: setup name, four 64-byte
[label:22][value:42] note entries, sensor location, and the three geo trigger
levels (0.3 -> 0.5 in/s) on a 48-byte channel stride.
Independent confirmation of the geo LSB: each channel block carries float32BE
3.10308 at label+24. 3.10308/10000 = 0.000310308 = _GEO_LSB_IPS to 8 figures,
and 10.0/3.10308*10000 = 32226.046 = the 32226.05 full scale. That value was
derived statistically from 991,415 rounding constraints in v0.30.0; the unit
reports it directly. It is exactly half Series III's 6.206053, so the ADC runs
10,000 counts per volt. Do NOT retune _GEO_LSB_IPS -- this corroborates it.
The `offset` field is NOT a single length formula: two frames are len, two are
len+2, and Series III's data[1]+2 reproduces neither. Recorded as observed
constants the device accepted; pinning the rule needs a capture with
differently-sized payloads. This doc has been wrong once by inferring a length
field -- not inferring this one.
Also adds scratch/mm_frame_parse.py, because S3FrameParser cannot see Micromate
responses at all (it scans for DLE+STX; Micromate responses start at a bare
STX). That is why the first pass at this capture looked like 12 unanswered
requests. 24/24 frames parse with 0 bad checksums.
Stale claims corrected: the "write half is not yet attempted" note, the
"empty unit" limitation (5 events since 2026-09-23), and the unsafe-until-agreed
list, which now distinguishes observed from exercised.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ru8Lg9HkkYvX9VWWo65SmL
serversdownandClaude Opus 5
c8d972f685