Re-Upload on previous thread

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Tesla's Buzz

Joined Feb 13, 2024
Hello everyone i previously shared my schematic for a custom pcb. now i have received the boards but when i try to upload the code i get the error saying
Sketch uses 237141 bytes (18%) of program storage space. Maximum is 1310720 bytes. Global variables use 21048 bytes (6%) of dynamic memory, leaving 306632 bytes for local variables. Maximum is 327680 bytes. v4.5.1 Serial port COM4 Connecting...................................... A fatal error occurred: Failed to connect to ESP32: No serial data received. For troubleshooting steps visit: Failed uploading: uploading error: exit status 2
i have tried pressing reset and enable buttons and everything. the board is esp32-wroom 32.
previous thread ""
what can i do to diagnose this problem


Joined Jan 27, 2019
Welcome to AAC.

Did you take the steps outlined in the document the error message linked?

Bootloader Won’t Respond [source]
If you see errors like “Failed to connect” then your chip is probably not entering the bootloader properly:

  • Check you are passing the correct serial port on the command line.
  • Check you have permissions to access the serial port, and other software (such as modem-manager on Linux) is not trying to interact with it. A common pitfall is leaving a serial terminal accessing this port open in another window and forgetting about it.
  • Check the chip is receiving 3.3V from a stable power source (see Insufficient Power for more details.)
  • Check that all pins are connected as described in Boot Mode Selection. Check the voltages at each pin with a multimeter, “high” pins should be close to 3.3V and “low” pins should be close to 0V.
  • If you have connected other devices to GPIO pins, try removing them and see if esptool starts working.
  • Try using a slower baud rate (-b 9600 is a very slow value that you can use to verify it’s not a baud rate problem).