Using BrewFlasher With ESP32 S2?

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Well-Known Member
Dec 27, 2013
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I'm trying to flash GravityMon 1.3 beta on an ESP 32 S2, and am struggling to get it to flash. I've had no issues with ESP8266 or ESP32 C3 V2. I've followed the BrewFlasher instructions for the S2 to set it to flash manually: hold "0", hit the RST button, then release "0". I'm pretty sure it's working properly because I get an LED flash when I hit RST, and then the disconnect/connect Windows USB sound when setting it to flash manually. In addition, the flashing will fail at the '1200 bps touch' stage if I don't set it to manual flash, but will proceed if I do. I'm using the same USB-C cable that's successfully flashed a couple of C3s, so don't think that's the issue either.

Any suggestions for what else to try would be appreciated.

This is the error message I'm getting at the end:
WARNING: ESP32-S2FNR2 chip was placed into download mode using GPIO0. can not exit the download mode over USB. To run the app, reset the chip manually.
To suppress this note, set --after option to 'no_reset'.
Firmware flashing FAILED. raised an error.

Try flashing again, or try flashing with a slower speed.

Alternatively, you may need to manually set the device into 'flash' mode.
For instructions on how to do this, check this website:
In case anyone comes across this later, BrewFlasher actually successfully flashed the GravityMon firmware to the ESP when I was getting this error. Over my head, but how the S2 operates via USB is different than ESP8266, and as a result BrewFlasher can't properly end the flash program. Ended up installing BrewPi on it instead, and it works just fine.

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