Unable to read/flash Vue - Pulling my hair out

[KidA001]

I am pretty experienced with ESPs, and in fact this is my second Vue 2 device. I flashed my first one a couple days ago and it went mostly smooth.

I am unable to backup or flash my Vue2 with my USB to serial adapter (same one I've been using). I have verified that there is continuity between the pins on the board and my USB Serial device. I even replaced the cables just to make sure. I have followed this thread to bypass the resistor on the TX pin which I had to do on my last vue. I know IO0 is pulled to ground.

No matter what I do it cannot read from the ESP on the board, but it is powered up. Running esptool.py flash_id returns nothing. When I'm watching the RX TX pins on my UART device it shows that the ESP is never sending anything out, though it is transmitting to the board.

Any help appreciated

Is there something else I'm missing?

[flaviut]

IIRC certain boards have series resistors that don't work well with certain serial dongles. Perhaps you can try soldering directly to the esp32 rx/tx pins.

[KidA001]

External 5V source did not make a difference

[flaviut]

yeah, I'm sorry :(

IDK what's going on here. Maybe the next step in debugging this (if you'd like) is powering the vue off an external power supply (the inrush power-on current always resets my serial dongle) while being connected via UART. The bootloader I believe prints some details about the boot process.

But I certainly don't have a well-tested procedure here or any really concrete ideas.

[KidA001]

I was wondering how to get logging from the device, but not totally sure. Honestly I have a new one coming tomorrow that I will try it on and swap it out of it works on the new one. If it doesn't I'll see about replacing my UART device. Appreciate the help, i'll post back what I find.

[KidA001]

Just a follow up - I received a new unit today and after soldering headers on and holding a pin by hand to the Tx pin on the board, I was able to flash it first try. I'll be sending the other unit back. Appreciate the help here

[clowrey]

Personally I wouldn't send a unit back that I likely broke myself... Replace the ESP32 module.

[KidA001]

Unit works fine on it's own when powered and can pair with the Emporia Vue app, it just can be custom flashed with custom firware for reasons that are unclear to me.