Hi John,
I know this is an older project but I hope you are able to clarify some details if you get the chance. I am attempting to replicate your project using the Arduino IDE and Linux as a baseline. I am taking notes to maybe share with others. I am no hacker-dev but this isn't my first microcontroller project either. I have a couple of ESP32 boards and an ETX-60AT. I currently have the Arduino IDE running with your project loaded. I fixed all of the compilation errors that came up due to missing libraries, and I can compile the project in the IDE.

1. You listed the Espressif IDF and Platform IO install in your documentation but I did not see the version of the Arduino-cli/Espressif IDF you used. I don't think this is really important at this point, but in the future it might help others if they knew what version was used or the last known to work, which I may be able to share soon.
2. The only library issue I came across was from the included SPIFFS.h and SPIFFSEditor.h files. My research indicates these files are from https://github.com/me-no-dev/ESPAsyncWebServer and https://github.com/me-no-dev/AsyncTCP . As far as I can tell these are not packaged for the Arduino IDE with the same syntax you used in the project. I had to clone them, compress the files in their respective src folders into zip files and add them to the Arduino IDE manually using the Library Manager. After this step everything compiles without errors. Are these the libraries you used?
3. I would like to try to use a TTGO T8 V1.7 ESP32 board for the project if I can get it to work. It has a lithium battery charge controller on board (but no discharge protection and maybe a poor regulator design). I am not asking for your help on my hardware tangent. As far as general project documentation: what is the ESP32 configuration you used and are any of the specific hardware configuration options of the ESP32 important here? If you open the Arduino IDE with Espressif IDF added to the board manager list in Preferences, and set the board to the generic "ESP32 Dev Module" you will see the options I am looking to clarify in context. I can trial and error my way through this if needed. The options are: Cores configuration for events and code execution(Core0:code/Core1:Events?), the CPU/Flash frequencies (80 or 40MHz), the flash mode(QIO/DIO/QOUT/DOUT), and the memory partition scheme(SPIFFS/OTA/etc. | Default= 4mb w/spiffs (1.2mb app/1.5mb spiffs)). I apologize if these should be obvious. I have not used the ESP32 much in the past.
4. Lastly, at the highest level of your project here, are the possible hardware configurations:

• ETX-AUX -> 1x ESP32 with WiFi server -> software connected device
• ETX-AUX -> 1x ESP32 with Bluetooth server -> software connected device
• ETX-AUX -> Arduino Mega -> 1x ESP32 with WiFi server -> software connected device
• ETX-AUX -> 1x ESP32 with ESPNOW -> 1x ESP32 with ESPNOW -> TTL Serial -> Computer
• ETX-AUX -> 1x ESP32 with ESPNOW -> 1x ESP8266 with ESPNOW -> TTL Serial -> Computer

Thanks for sharing the project and taking the time to read this.
-Jake

Is it possible to port the ESP32 or Arduino versions of the code to run on a RPi using GPIO? I'd like to have more processing and communications/interfacing capability available than is possible with the Arduino.

Hi John,
Thanks for your work. I have ordered the ESP board from JLC, but I am a little confused
You make several reference to a an arduino controller - but all the code seems to be for an ESP
Did you move from Arduino to ESP to get wifi functionality ?
Is there a pure arduino version ? It looks like the level shifting would be easier with arduino - plus I have a mega sat on my desk, and I have to wait for the ESP PCB to come from China

Sorry to raise this as an issue, but it seems the only way to have comms on this platform

Lee