fix(AS7341): AS7341 overflow, spectral coefficients and new PAR coefficients - #7
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fix(AS7341): AS7341 overflow, spectral coefficients and new PAR coefficients#7Ludo-lab wants to merge 6 commits into
Ludo-lab wants to merge 6 commits into
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get_PAR() assigned `counts * Spec_COE_n` into a uint16, which wrapped rather than saturated. Full scale is (ATIME+1)*(ASTEP+1) = 50000 counts, but the weights (12,10,11,10,10,9,7,4,1,1) push the reported word past 65535 from ~11% of that -- F1 wraps above 5461 counts. A bright reading therefore came back looking like a dark one, and since PAR was summed from those same wrapped words, PAR collapsed with them: at F1 = 5462 counts the old code reported word 8 and PAR 0.19 where the true values are 65535 (pegged) and 1573. - Compute PAR in get_PAR_raw() from the unclamped counts in a uint32 accumulator. Coefficients and operation order are otherwise untouched, so the result is bit-identical to the old one whenever nothing overflowed (checked over 100k non-overflowing vectors against the previous algorithm). - Saturate the ten 16-bit channel words at 65535 instead of wrapping. A pegged value is monotonic and obviously at the rail; a wrapped one is silently wrong. Framing and the 24-byte length of cmd 31 are unchanged -- only values differ, and only under light that used to wrap. - Add binary cmd 35 get_spec_raw: 0xA1 + 32 B + 0xF0 carrying the unscaled counts plus format/atime/astep/gain_low/gain_high/flags, so a host can normalise across exposures and detect saturation. Byte-explicit and naturally aligned, so it avoids the ESP32-default-alignment coupling that froze the cmd 33 structs. Additive: cmd 31 is untouched and pre-v1.2.0 images are unaffected. Hosts gate on cmd 33/2, since an unknown opcode hits `default:` and draws no reply at all. - Guard spec_meas.h, which was unguarded while it held only idempotent declarations and now defines a type. The ambyte side is deliberately not updated yet; cmd 31 still answers exactly as before, so deployed loggers keep working untouched. Re-runs plans/HW_CONFORMANCE.md (logged in section 7, layout in section 6). Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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creation Command 35
adjustment spec coefficients