ESP32 Forum

Hi everyone,
I designed a board with an ESP32-C3-MINI-1U, and ordered it from JLCPCB (manufacture and assembly).

I copied the schematic of the ESP32-C3-DevKitM-1 for the programming circuit via UART only, through USB (with USB converter).
I had to use this method because I'm using another µC on the board and need access to it through USB.

My issue is :
I can't program it at all. Everytime it returns "A fatal error occurred: Failed to connect to ESP32-C3: Wrong boot mode detected (0x0)! The chip needs to be in download mode." which is supposed to be the right boot mode (0x0). Right ?
I tried Arduino IDE, ESP-IDF, esptool.py with cmd.exe. Always the same.
With the exact same config and program, it worked with the DevKit Board.

I looked with an oscilloscope, I've got the same signals on DTR/RTS/EN/BOOT on DevKit Board and mine.
I looked over the power supply, it's stable.
I tried 4 different boards (I ordered 10pcs), all the same.

So I'm out of solution to explore (I can try to rewire the ESP32 to use the inside programming tool of ESP32, but it is not a durable solution for me).

Can someone help me ?
I already asked Espressif to help, but only got 1 short reply and never again.

Can you post your schematics?

Hi,
I can't post it entirely.
I reached here for help because I sent an email to Espressif for help and never got an answer.
So I attached the interesting part for my topic, and hid some names.
Thanks for your time to help.

What level is BLE_STATE on startup? According to the datasheet, GPIO8 needs to be high to successfully enter download mode.

THANK YOU very much !
You are right !
I've looked about 50 times in the datasheet and the tab about Pin Configuration for Download Boot and didn't remember the GPIO8!
You give me the right question to clarify my view ! Too much time on it to still get a global view !

So anyone unable to solve this issue the possible solution could be the boot mode. It needs to be changed to flash the application/code on the flash. Read the datasheet for ESP-32 C3 mini 1u or ESP-32 C3 mini 1 its the pin 2,8,9 (according to the datasheet MAKE SURE THOUGH), they go by the name Strapping Pins in the datasheet. These pins must be set at a certain voltages before the MCU turns on or restart and then the program could be uploaded without any problem.