0

Arduino Uno Com Port - changes Com Port 3 to Com Port 5
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

Arduino Uno Com Port - changes Com Port 3 to Com Port 5

by JHRrec on Mon Nov 20, 2017 1:55 pm

Purchased 1st Arduino Uno R3 around last February or so. WORKED GREAT!
Purchased 2nd Arduino Uno R3 a few months later. It BLINKED properly when plugged in, but changed com port 3 to com port 2 when I loaded blink program. It was useless!
I was so confident products from Adafruit would work, I did not even try it for about 60 days after purchase. Thought it was a
fluke. I thought it was too late to get support from Adafruit.

Purchased 3rd Arduino Uno R3 on Nov. 7, 2017. Same problem as 2nd Arduino.

Details:

Plug 1st board in, uploaded Blink, worked fine. Can run many programs just fine. Still works fine.

Plug 3rd board, hit upload, and get error message:
Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
avrdude: ser_open() can't open device "//.com3: The system cannot find the file specified.

When I click TOOLS > PORT it shows: " Com2 (Arduino/Geniuno Uno)

I've tried changing port back to 3, using Device Manager, etc, and nothing works.

I tried to Burn Bootloader on 2nd unit, and had problems.

What is different? Why does the 1st Arduino work, 2nd and 3rd Arduinos don't?

JHRrec
 
Posts: 1
Joined: Fri Nov 10, 2017 6:46 pm

Re: Arduino Uno Com Port - changes Com Port 3 to Com Port 5

by adafruit_support_bill on Mon Nov 20, 2017 2:09 pm

The UNO does not set the com port number. That is assigned by your computer. It is not unusual for Windows to assign different COM port numbers to different USB/Serial devices like Arduinos. If it is showing up as COM2 in device manager, then you should select COM2 in the IDE.

adafruit_support_bill
 
Posts: 63486
Joined: Sat Feb 07, 2009 10:11 am

Please be positive and constructive with your questions and comments.