I allowed myself a tiny mod to your App. Now it can be launched from the SD card under SD-Menu from tobozo. https://github.com/tobozo/M5Stack-SD-Updater.
Modification consists in main.c mod and extra libraries. Just unzip Matroska.zip to project folder and build. Resulting firmware.bin in .pioenvs\m5stack-core-esp32
is compatible with tobozo loader.
Zip here: https://yadi.sk/d/8sroLeG_3YMfwe
I can power it through my mobile phone charger or a battery pack, just using a tiny USB3 Adapter; and I can power it off my solar panel. I just like the idea of having a web server (or whatever else I made ...) that I can plug into an AC socket.
I gather you are talking about the internal MBUS GPIO pins - that connect the modules together.
The pin pitch - distance between the pins - is 2.54 but the pins are height reduced compared to those found on a standard GPIO header - too SHORT for Dupont connectors to attach.
The MBUS pins are intentionally height reduced in order to minimise the overall height of the M5Stack.
It is possible to source a third party full height 30 pin GPIO header if needed, or you can make one using a GPIO for Arduino or Raspi. You could get a PCB made to go with it, based on the files available on github, see here.
That seems a weird error to get from running M5Stack's simple Hello sketch which does not include a poweroff function. (?).
Also I don't know the "ResetReason" sketch that you referred to. Where did you find this ?
(1)OK it seems you have the M5Stack library installed in the correct place.
(2) Is the Espressif ESP32 library installed ? Check: C:\Users\█████\Documents\Arduino\Hardware\espressif\esp32\libraries . If you don't have files there go to M5Stack setup guide and install them.
(3) As PépéMax suggested, in the Arduino IDE, check that the M5Stack is selected as the board that you are using with the IDE. On the Arduino menu go to /Tools/Board . The M5Stack should be set here as the board you are using.
'...some function of the ESP32 does not work yet for the M5Stack library like analogWrite()
Just to clarify, as I understand it, the issue is that not all functions available on Arduino or ESP8266 boards are available at present on ESP32 boards in general - eg: analogWrite();. That is, the problem is not specific to M5Stack boards - it effects all ESP32 boards. Referenced here