Add stable CYD firmware, USB calibration wizard and complete setup guide

2026-09-12 10:18:49 +02:00
parent 1eb65d8f71
commit 94546cf727
43 changed files with 9312 additions and 45 deletions
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+# XPT2046 input stabilization
+
+Based on ESPHome 2026.6.2's `esphome/components/xpt2046` (license alongside).
+The sample handoff in `touchscreen/xpt2046.cpp` and filter/calibration members
+in `touchscreen/xpt2046.h` differ from upstream. `touch_filter.h` is local.
+
+The installed CYD produced widely separated coordinates at first contact.
+The filter requires three samples within 100 ADC units before reporting a
+new contact, ignores isolated large jumps, and requires two absent-pressure
+samples before reporting release. Normal continuous drags use a small
+moving average; large movements are accepted after three stable samples.
+
+Use polling (20 ms in the device configuration), not an IRQ-only setup: the
+filter needs follow-up samples while confirming a contact or release.
+Run `tests/test_touch_filter.cpp` when changing the filter or updating ESPHome.
+
+An optional affine raw-coordinate correction defaults to the identity.
+The device profile sets its six coefficients at boot, fitted to median
+filtered corner readings from this particular panel. Raw diagnostic getters
+still expose the original filtered ADC values, allowing recalibration without
+mistaking corrected coordinates for physical measurements.