ESP32 Forum

Posted: **Fri Jul 22, 2022 12:13 am**

I have a regular ESP32-C3-WROOM-02-H4 module on a simple replica dev landing board.

I copied the C3 dev board schematic. However, unless I pull up GPIO8 - the bootloader doesn't go into serial mode. (I don't have to pull up GPIO2 at all)

Does anyone know how the dev board version of the wroom put bootloader into serial mode without pulling up the strapping pins?

Do I have to write a custom bootloader or permanently pull GPIO8 up?

Posted: **Fri Jul 22, 2022 1:55 am**

Datasheet says GPIO8 needs to be 1 for serial bootloader. Not sure what devboard you copied, but the schematics of the esp32-c3-devkit-02 has R20 as a pullup.

Posted: **Sun Jul 24, 2022 9:37 am**

Do not know about the GPIO8 but GPIO0 should be used to pull-down on reset to run the serial bootloader. Otherwise it will run the program in the flash..

https://docs.espressif.com/projects/esp ... ction.html

Doesn't your board have boot button?

ESP32 Forum

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