Measure and improve latency

[JohnAZoidberg]

Using #define DEBUG_MATRIX_SCAN_RATE in config.h prints the matrix scans every second. Currently we're at 107Hz. If matrix_scan_custom returns immediately it's about 45kHz.

Approaches:

• [ ] Don't scan temperature (at least not every ADC conversion)
• [ ] Reduce buffer depth
• [ ] Check how much we actually need to sleep after selecting a row with the mux

References:

• https://michael.stapelberg.ch/posts/2021-05-08-keyboard-input-latency-qmk-kinesis/

[JohnAZoidberg]

Reduced the sleep after mux selection to 1us. Now we're at ~300Hz.

[JohnAZoidberg]

Not converting the temperature increases frequency to ~500Hz.

[KarlK90]

Also consider using the per key asym_eager_defer_pk de-bouncing algorithm instead of the default global de-bouncing implementation. https://docs.qmk.fm/#/feature_debounce_type?id=selecting-an-included-debouncing-method

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[github-actions[bot]]

This issue has been automatically closed because it has not had activity in the last 30 days. If this issue is still valid, re-open the issue and let us know. // [stale-action-closed]