(Solved) How to program "fryed" ESP32 Dev Module (WROOM-32 chip) over serial

Other Hardware 3rd Party Boards
1

I got my hands on an ESP32 that was used with an 5V LCD/keypad-shield :cry: and doesn't power on anymore when plugged in to any USB power source.
However, when powered with 3.3V the red power-LED lights up and I've managed to get this boot-message over a serial connection ("broken" ESP32 connected to a working ESP32 with a "serial-receiver-sketch") :

ets Jun  8 2016 00:22:57

rst:0x1 (POWERON_RESET),boot:0x
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0
mode:DIO, clock div:1
load:0x3fff0018,len:4
load:0x3fff001c,len:1044
load:0x40078000,len:8896
load:0x40080400,len:5816
entry 0x400806ac

My hope is that the chip is still working and only the USB/power converter is broken.

Is it still possible to program the chip over serial?
And if so, can I use a Arduino Nano + Logic-level-converter/ESP8266 Node MCU / ESp32 DEV Module for that
or do I have to use a USB-serial-converter like in this tutorial?

Edit: solved, posting solution tomorrow (UTC)

2

It should be programmable but the 3.3V consumes a fair amount of power when programming. This voltage needs to be clean and no an arduino does not have enough power to support this load. I would suggest you replace the 3.3V regulator, it appears that has been blown or possibly a trace blown off the board.

3

I've managed to program the ESP32 by using a ESP8266 NodeMCU (ESP32 Dev Module should also work)
and connect it to the "fryed" ESP32 the following way:

ESP8266 Node MCU          WROOM-32
GND                ->     GND
3.3V               ->     3.3V
TX                 ->     TX
RX                 ->     RX
EN -> GND          |      IO0/GPIO0 -> GND

Make sure that the WROOM's IO0/GPIO0 is connected to ground before you plug it in (to enter program-mode)
and that the ESP8266's EN pin is also connected to ground (to prevent it from booting and interfere the serial connection with the WROOM-32 and the USB controller)

My board has no IO0/GPIO0 pin so I had to make the connection directly to the chip

4

gilshultz:
It should be programmable but the 3.3V consumes a fair amount of power when programming. This voltage needs to be clean and no an arduino does not have enough power to support this load. I would suggest you replace the 3.3V regulator, it appears that has been blown or possibly a trace blown off the board.

Measured power consumption (for both boards) during upload: 0,2485W*
Measured power consumption (for both boards) while WROOM-32 is connected to WiFi and sending data: 0,792W*
*measured with "Voltcraft PM-37", so the values are not very accurate

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