ESP32 upload using serial communication


I have built a project in Arduino IDE that uploads and runs successfully while using usb cable (also powered up typically using usb).

But however, I want to upload it using serial communication. For this purpose, I have a usb to serial converter, whose Rx and Tx have been connected to Tx and Rx of the board respectively. Also the board is powered up using 5V external supply and the ground from the board is connected commonly to the supply and the serial converter.

And this does not seem upload my code.

What am I doing wrong here and how else can I upload my project using uart. Please help me with your kind inputs.

Thank you

How do you provide the reset?

Reset for the board?

As of now, I have not included any reset. Could you please tell me how to include it?

It wont.

To upload code via Serial on an ESP32, you need to connect DIO0 to ground, assert and release Reset (a pin often labelled EN) then upload code.

And you should provide us with a link to the 'ESP32' you are using, there are lots of variations.

Thank you @srnet. I'll do that now.

Is DIO0 same as D0?

I am using ESP32-WROOM-32U.

Just the bare module ?


Yes. Just the bare board with a bluetooth antenna.

OTA would be simpler.