SC-F001/logtool/debug-notes.md

Logtool Debug Notes — 16 MAR 2026

Problem

storage-16MAR2026-1728.bin not parsing correctly.

Root Cause (SOLVED)

Two issues in parser.py:

1. Unrecognized file format

The file format is [4B tail BE][4B head BE][raw log data] — no JSON header.

• head - tail == file_size - 8 (the raw log data is exactly the flash region from tail to head)
• The old HTTP format was: [4B json_len BE][json][4B tail BE][4B head BE][raw log data]
• The parser's autodetect only recognized the old HTTP format (and required json_len < 8192)
• Fix: Added detection for bare tail+head format in autodetect_and_parse()

2. Type-first vs type-last detection failure

The log entries use type-first format: [len][type][payload] But _try_detect_type_first() returned False because:

• First entry had type=0x00 at both positions (ambiguous)
• Timestamp was near-zero (RTC not yet set), so timestamp sanity check failed
• Function gave up after only 1 entry (break at end of loop)
• Fix: Loop over multiple entries (up to 200), added voltage sanity check (0.5-60V)

Verification

• 54,831 entries parsed successfully
• FSM states: IDLE (51169), JACK_UP (1078), DRIVE (994), etc.
• Voltages: 3.3V–13.3V (reasonable for 3S LiPo system)
• Timestamps: Jan 13 – Feb 6, 2026 (after RTC set)
• Old HTTP-format .bin files still parse correctly