ESP8266 Community Forum

Hi,
I've used ESP8266/ESP32 in a few projects in the past (usually on some Adafruit board); but now I have a small project that has the ESP8266 as a peripheral to another microcontroller (Teensy4.1). I have an 8-pin ESP8266 module wired up to the Teensy, so I can communicate with it over RS232 and I have GPIO pins from Teensy to control RESET and GPIO0 of the ESP8266. All that works just fine, but now I need to be able to flash a new image onto the ESP8266 using the Teensy. I started this project taking for granted that "somewhere" there would be a C program already written for this; however, I have not found anything. Can anyone point me to what I need to be able to update ESP8266 flash using another microcontroller (written in C)?
Thanks,

You can Flash Firmware on ESP8266 using Arduino. I am not sure if it will help you, as you're using Teensi.
https://create.arduino.cc/projecthub/pr ... ule-e1f758

This really doesn't give us much to go on.

You've said you're using RS232 but how exactly are you communicating with the ESP? Is this your own firmware and you're using your own commands or is this the standard AT firmware supplied by Espressif?

Either way you're probably going to have to unplug the ESP and connect it to a serial port on your computer to flash a new update