From e1a6fd53862f2a89af67cbc80e88c5680ea6433d Mon Sep 17 00:00:00 2001 From: Brian Harrison Date: Tue, 28 Apr 2026 00:05:51 -0400 Subject: [PATCH] fix(protocol): remove auto-detection of frame mode and ensure extra chunks are always used for valid waveform footer --- CLAUDE.md | 24 ++++++++++++++++++------ minimateplus/protocol.py | 29 ++++++----------------------- 2 files changed, 24 insertions(+), 29 deletions(-) diff --git a/CLAUDE.md b/CLAUDE.md index 4196b5f..b3fb482 100644 --- a/CLAUDE.md +++ b/CLAUDE.md @@ -350,14 +350,20 @@ Do NOT use fixed absolute offsets for sample_rate or record_time. **SUB 5A (bulk waveform) TCP frame splitting — confirmed 2026-04-27:** Over TCP via cellular modem, each 5A chunk request that produces a single ~1100-byte -A5 response over direct RS-232 arrives as **two separate, complete S3 frames** of -~550 bytes each. This is because the device sends its RS-232 response as multiple -frames, and the modem's Data Forwarding Timeout (~100-150 ms) delivers them to us -as separate TCP segments, each parsed as a complete S3 frame. +A5 response over direct RS-232 may arrive as **two separate, complete S3 frames** of +~550 bytes each ("2-frame mode"). The modem's Data Forwarding Timeout (~100-150 ms) +can split the RS-232 response into two TCP segments, each parsed as a complete S3 frame. +Under different modem/timing conditions the full ~1100-byte response arrives as **one +S3 frame** ("1-frame mode"). + +**Both modes require `extra_chunks_after_metadata=1`** (the extra chunk at metadata_counter ++ 0x0400). The device's waveform footer data lives at circular-buffer address 0x1C00 for +this event; the terminator frame must be sent at 0x1C00 (not 0x1800) to receive it. Example for a 2-second Continuous event (BE11529, key=01110000) via TCP: -- 1 probe frame (554 B) + 5 chunks × 2 frames (556-573 B) + 1 extra chunk × 2 frames + 1 terminator (208 B) = **14 A5 frames** -- All 14 frames contribute body data; using all of them gives the correct 6864-byte file. +- **2-frame mode:** 1 probe frame (554 B) + 5 chunks × 2 frames (556-573 B) + 1 extra chunk × 2 frames + 1 terminator (208 B) = **14 A5 frames** → 6864-byte file +- **1-frame mode:** 1 probe frame (~1097 B) + 5 chunks × 1 frame (~1079-1113 B) + 1 extra chunk × 1 frame (smaller, tail of event) + 1 terminator → **8 A5 frames** → 6864-byte file +- All frames contribute body data; using all of them gives the correct file. **Fix (confirmed 2026-04-27):** `_recv_5a_batch()` in `protocol.py` collects ALL A5 frames per chunk request before the next request is sent, using a 0.5 s batch @@ -365,6 +371,12 @@ timeout after the first frame to catch the ~150 ms delayed second frame. `write includes ALL body frames without skipping — the extra chunk's frames are part of the body data, NOT padding to be discarded. +**WRONG earlier hypothesis (do not re-introduce):** An attempt was made to auto-detect +1-frame vs 2-frame mode from the probe frame size and skip the extra chunk when +`probe_data_len >= 700`. This was wrong — the extra chunk is always needed to advance +the device's internal state to the footer address. The `_probe_is_large` branch was +removed 2026-04-27. + ### Required ACEmanager settings (Sierra Wireless RV50/RV55) | Setting | Value | Why | diff --git a/minimateplus/protocol.py b/minimateplus/protocol.py index 159a1a9..6f2e874 100644 --- a/minimateplus/protocol.py +++ b/minimateplus/protocol.py @@ -614,31 +614,14 @@ class MiniMateProtocol: [f"0x{f.page_key:04X}" for f in probe_batch], ) - # Auto-detect frame mode from probe response size. - # - # Two observed TCP modes (confirmed from 4-26-26 and 4-27-26 captures): - # - # 1-frame mode (RS-232 / fast TCP): probe returns 1 large frame (~1100 B). - # Each subsequent chunk also returns 1 large frame. The probe contributes - # ~999 bytes of ADC body data. The correct term_counter = metadata_counter - # + 0x0400, which returns ~702 bytes of tail+footer — NO extra chunk needed. - # - # 2-frame mode (TCP frame-splitting): probe returns 1 smaller frame (~554 B). - # Each subsequent chunk returns 2 smaller frames (~550 B each). The probe - # contributes only ~487 bytes. The missing ~512 bytes of body data must come - # from an extra chunk after metadata, terminating at metadata_counter+0x0800. - # The caller's extra_chunks_after_metadata value (default 1) covers this. - # - # Threshold 700 B sits comfortably between the two observed probe sizes (554 vs - # 1097 bytes) and is robust to minor variation. - _probe_is_large = ( - len(probe_batch) == 1 and len(probe_batch[0].data) >= 700 - ) - _effective_extra_chunks = 0 if _probe_is_large else extra_chunks_after_metadata + # Log probe frame size for diagnostics. + # The device always needs extra_chunks_after_metadata chunks after the + # metadata frame before termination to prime the valid waveform footer. + # This holds regardless of TCP frame size (1-frame vs 2-frame mode). + _effective_extra_chunks = extra_chunks_after_metadata log.warning( - "5A probe data_len=%d _probe_is_large=%s effective_extra_chunks=%d", + "5A probe data_len=%d effective_extra_chunks=%d", len(probe_batch[0].data), - _probe_is_large, _effective_extra_chunks, )