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Error opening serial port ‘COM

Q&A Forum › Category: ESP32 › Error opening serial port ‘COM
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Michael Nicholas asked 5 years ago

Hi,

Could not find Com Port 4 in Device Manager when Sparkfun ESP32 board was plugged in

Was working previously with same usb cable running same scripts

Port is gray in “Tool” drop down

Tried several USB ports on Windows machine

Thanks

6 Answers
0 Vote Up Vote Down
DK answered 5 years ago

Hi
 
Try changing your usb cable …
Not all cables carry data and power …
Regards

0 Vote Up Vote Down
Rui Santos Staff answered 5 years ago

Hello Michael, did you install the USB drivers for your ESP32 dev board?

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Michael Nicholas answered 5 years ago

Thanks to both of you for your responses
I swapped cables that I am sure I used before (actually both of them I believe did work at one time).  One other symptom, the light next to the usb port flashes yellow. Anyway, I got the following error message;
 
Arduino: 1.8.9 (Windows 10), Board: “Adafruit ESP32 Feather, 80MHz, 921600, None, Default”

WARNING: Category ‘Actuators’ in library Grove – Motor Driver TB6612FNG is not valid. Setting to ‘Uncategorized’
Sketch uses 647602 bytes (49%) of program storage space. Maximum is 1310720 bytes.
Global variables use 38928 bytes (11%) of dynamic memory, leaving 288752 bytes for local variables. Maximum is 327680 bytes.
esptool.py v2.6
Serial port COM4
Traceback (most recent call last):
  File “esptool.py”, line 2959, in <module>
  File “esptool.py”, line 2952, in _main
  File “esptool.py”, line 2652, in main
  File “esptool.py”, line 222, in __init__
  File “site-packages\serial\__init__.py”, line 88, in serial_for_url
  File “site-packages\serial\serialwin32.py”, line 62, in open
serial.serialutil.SerialException: could not open port ‘COM4’: WindowsError(2, ‘The system cannot find the file specified.’)
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.
 
Thanks,
Mike

0 Vote Up Vote Down
Michael Nicholas answered 5 years ago

I have run the board and operated components from the Web.  The Laptop Device Manager says for Com Port 4…
<Currently, this hardware device is not connected to the computer. (Code 45)
To fix this problem, reconnect this hardware device to the computer.>
And it says  Silicon Labs CP210x USB to UART Bridge (COM4) in the General Tab
The Port settings are, 9600 bps, 8 bits, no parity and one stop bit
The driver revision is 6/20/2019

0 Vote Up Vote Down
DK answered 5 years ago

Hi

Redo setup again

set the boardManager for your version of esp32 Image

  • learn.sparkfun.com/tutorials/esp32-thing-hookup-guide

But I use Geekcreit Board

I hope you get it working …
DK

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Rui Santos Staff answered 5 years ago

Hello Michael, if it used to work before that’s definitely weird… Do you have multiple boards that you can use to test your setup?

  • Remove the board from your computer (unplug the USB cable)
  • Open Arduino IDE > Tools > Port
  • What do you see in your Ports Menu?
  • Then, plug your board to your computer: go to Tools > Port. Do you see a Port appearing?

Thanks!