ESP32 error uploading sketch

Hi, I’m trying to upload an example from a library which i found on the internet (RCSwitch - R433 RFID), but im stuck with this error:

Arduino: 1.8.5 (Windows 10), Board: "ESP32 Dev Module, Default, QIO, 80MHz, 4MB (32Mb), 921600, None"

WARNING: library rc-switch-2.6.2 claims to run on (avr, esp8266) architecture(s) and may be incompatible with your current board which runs on (esp32) architecture(s).
Archiving built core (caching) in: C:\Users\bunos\AppData\Local\Temp\arduino_cache_177451\core\core_espressif_esp32_esp32_PartitionScheme_default,FlashMode_qio,FlashFreq_80,FlashSize_4M,UploadSpeed_921600,DebugLevel_none_8135f9cbd41177003cfcd103bac1af93.a
Sketch uses 165289 bytes (12%) of program storage space. Maximum is 1310720 bytes.
Global variables use 11616 bytes (3%) of dynamic memory, leaving 283296 bytes for local variables. Maximum is 294912 bytes. v2.3.1
Traceback (most recent call last):
  File "", line 2637, in <module>
  File "", line 2630, in _main
  File "", line 2355, in main
  File "", line 193, in __init__
  File "site-packages\serial\", line 88, in serial_for_url
  File "site-packages\serial\", line 62, in open
serial.serialutil.SerialException: could not open port 'COM3': WindowsError(31, 'A device attached to the system is not functioning.')
Failed to execute script esptool
the selected serial port Failed to execute script esptool
 does not exist or your board is not connected

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.
  • I’ve already re-installed Silicon Labs CP210x USB to UART Bridge driver (it is indeed showing as my COM Port on device manager)

-I’m wiring Conversor TTL RX to ESP32 TX, Conversor TX to ESP32 RX, Conversor 3v3 to ESP32 3v3 and Conversor GND to ESP32 GND. I also set up two buttons for ESP32 EN and GPIO0 (had to do that in order to flash works the last time). But it’s not working now…

I don’t know what might be causing this issue now…Could anyone please help me?

Some additional data might produce a more informed answer and also help us with similar issues.

Which ESP32 board are you using, and which Arduino Boards Manager package?

Have you been able to run the simplest LED blink on this ESP32 board?

Is your OS, Arduino software, and USB cable working on other genuine Arduino brand boards?

which Arduino Boards Manager package?

It looks like he is using Python scripts for the upload.

The Python tool is trying upload on COM3 but whether the Silicon Labs CP210x adapter is indeed on COM3 we don't know.


Could be, however I think the ESP32 build tools use python. I’m using the sparkfun ESP32 Thing and their software package uses v2.1

after the version is printed it goes on with
and uploads and runs stub and then that uploads and runs my sketch.

It’s a pity that there is no central Arduino support for the ESP32 hardware. It’s a step ahead of the Microchip stuff.

The original problem could be something as simple as not setting the Flash Frequency, Upload Speed, and Port in the Tools menu of the Arduino IDE, or it could be bollixed Windows USB drivers.

I came across
Looks very interesting and there is a forum (not Espressif’s).

I'm using a simple adapter plate to connect my esp32.

On my device manager it shows Silicon Labs Cp21x on my COM port 3.

Maybe there is a problem on my flashing settings? Could you share the configuration for flashing it?

It already worked once...i really don't remember what have i changed on my settings

Thanks in advance

I don't have the ESP32

Look for a tutorial on how to flash it.