ESP32 Forum

Hello,

so i have a "TTGO Lora32-Oled V1" board. It was working fine yesterday and now I get this output, when I try to upload anything

esptool.py v3.0-dev
Serial port /dev/ttyUSB0
Connecting........_____....._____....._____....._____....._____....._____....._____

A fatal error occurred: Failed to connect to ESP32: Timed out waiting for packet header
A fatal error occurred: Failed to connect to ESP32: Timed out waiting for packet header

I tried all the boot, rst pin options. But then looking at the serial monitor I don't see anything. So no "waiting for download" nothing.
I tried connecting GND to GPIO0, still nothing.
The serial connection is there though, since if I write in my terminal. I find USB0 only than the board is connected.

I have another board here and this one flashes fine.

So I guess my board is broken or not? What I don't get is how it was working fine yesterday and now it doesn't anymore I didn't change my circuit.

Interestingly when I started my circuit today I didn't get any serial output from the esp32, so it must have broken at some point. I'm kind of worried I'm gonna break another one.

I either power it through my laptop or through a Teensy 3.6, the connections are:
ESP32<-> Teesny3.6
GND <-> GND
3.3V <-> Vin
GPIO23 <-> GPIO7
GPIO13 <-> GPIO8

I would really appreciate some help.

Only issue is that Vin is generally used for e.g. 5V input; 3.3V is technically too low for it, and depending on the board, it may actually have fed 5V back into your Teensy if you had USB connected. That shouldn't be able to damage the ESP32 board, though.

So if I would connect my Teensy to the 5V it wouldn't break my board?