@mnwh If your error has something to do with the "ADC1_GPIO35_CHANNEL not defined" error I got, then you can "simply" insert this #include "soc/adc_channel.h" into the \Documents\Arduino\libraries\M5EPD\src\M5EPD.cpp. I wrote this in a new line (line 4) It's caused by a change from espressif 3.3 to 4.4. Have fun, undefined