Possible use of ESP32 instead of HC-05 for OTA?

[JackBlair87]

Hello!
Thank you for all your work on this, the results are very impressive. Do you think it is possible to replace the HC-05 you use in your setup to an ESP32? My eventual goal is to send my .bin file over Wifi to the ESP32, then have it flash a Teensy4.1 with that new program. If it is possible, what would the code need to look like on the ESP32 to make the OTAs happen?
Thanks for all your help.

[paynterf]

Uh, I think you mean 'send your HEX file over to the ESP32, then have it flash a Teensy'...

All you need to flash the Teensy is a serial connection over which you can send the HEX file once the 'update_firmware' function in the Flasher_X code is called. In my setup I have a 'CheckForUserInput()' function that runs every time through the loop, and as one of the many possible commands that can be sent using this facility, the 'U' character causes 'update_firmware()' to run and then this latter function manages the HEX file transfer. Whether you use a HC-05 BT device (as I did for the post I wrote), or a Wixel (another post) or a Raspberry Pi Zero, or an ESP32 doesn't matter to the process. All you need for your ESP32 code is something that can accept a HEX file from your PC (possibly storing it temporarily on the ESP32) and then trigger the 'update_firmware()' function on the Teensy via one of the many serial ports on the Teensy.