ESP32 Forum

Dear All,

I would like to know the sequence of backend commands that run when we press the Start button in the ESP Flash download tool. I am planning to upgrade the firmware of the ESP-WROOM-32D Module using the passthrough method as shown in the attached image. To do that i need to write a firmware in the MCU which will incorporate the appropriate command sequence to pass through the firmware sent from the ESP Flash download tool.

Request you to provide some information regarding the commands and if anyone has tried this implementation, request you to provide some information regarding the bottlenecks faced in this implementation if any.

Thanks in advance

Why wouldn't you just use it as a transparent bridge and pass everything?

WiFive wrote:Why wouldn't you just use it as a transparent bridge and pass everything?

Dear @WiFive,

I would like to use it as a transparent bridge and pass everything. But dont we need to implement a logic in the MCU Firmware to Pass through, which will need to know the task it has to perform to sync with the commands executed by the Flash download tool after the Start button is pressed.

Thank you

Read up on how the dev boards use a dumb usb-uart chip with transistor circuit to put chip in download mode and then decide how you want to do it.

WiFive wrote:Read up on how the dev boards use a dumb usb-uart chip with transistor circuit to put chip in download mode and then decide how you want to do it.

Dear @WiFive,

Thank you for your inputs.

Regards,
Subbash