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F-135+, serial 17157

Read by Mats Fagerberg (thetalkingdrum), 24 August 2026. Everything below is what this particular unit showed; see the dump comparison for how it sits against the others.

Decoded contents

Field Value
Scanner type (0x00C) 1351 = F-135 Plus
Serial 17157
DpiBase4_35: Offset / MotorSpeedPlus / MotorSpeedPlus_Ir 34 / 25498 / 19107
DpiBase8_35 66 / 11332 / 7490
DpiBase16_35 68 / 5847 / 4793
NegMatrix (3×10, per row: R G B R² G² B² RG GB BR const) diag 0.28860 / 0.31628 / 0.32606, consts 162.075 / 401.272 / 607.741, quadratic terms ~0
PosMatrix 0.25 diagonal, no cross terms or offsets
MotorAdjust ×12 1000, 1008 alternating

This unit has the highest Offset values of any unit read: 34 / 66 / 68, against 27–30 / 54–58 / 55–60 everywhere else. If Offset is the per-unit start of the imaged region along the CCD line, as calibration.md infers, then this unit sits about 14 px further into the sensor at base 16 than the lowest one read. It widens the known spread considerably, and any implementation that hardcodes a window start rather than reading this word will be furthest wrong here.

Chip health

Clean, and the only fully healthy F-135 Plus read so far. All four copies validate, and the two reads of section A's primary, taken in separate power cycles, are byte-identical.

Copy CRC Result
Section A primary 0x96cec048 valid
Section A backup 0x96cec048 valid, byte-identical to primary
Section B primary 0x873e6ed3 valid
Section B backup 0x873e6ed3 valid, byte-identical to primary

What this unit established

Section B is byte-identical to 5963's and 16402's, same CRC 0x873e6ed3. Having a second independently-read F-135 Plus to compare against is what allowed section B to be scoped as a per-model default rather than assumed universal across the family. The base F-135 (2233) differs from all three Plus units in one payload byte.

Files

File Size Notes
eeprom_0x52_sectionA_primary.bin 398 B CRC valid
eeprom_0x52_sectionA_backup.bin 398 B CRC valid, identical to primary
eeprom_0x52_sectionB_primary.bin 36 B CRC valid
eeprom_0x52_sectionB_backup.bin 36 B CRC valid, identical to primary
eeprom_0x52_sectionA_primary_read2.bin 398 B second read, identical
SHA256SUMS hashes for the above

No boot personality (0x51) read for this unit. The scanner was power-cycled between the two reads, so the pair is a check across power cycles rather than two reads in one, which is the comparison that shows a dump is what the chip stores rather than what one read happened to return. Read on macOS via pakon-tlx-macos (tools/eedump.py).