COM ports different on UNOs

I use three Unos for the same project, connecting one Uno at a time, since each is connected to different hardware. When I connect Uno 1 it shows COM 3, Uno 2 shows COM 4, while Uno 3 shows COM 5 on the IDE. When I try to download my script only COM 4 allows the program to download. So I need to keep changing the external hardware over to Uno 2. This is driving me crazy. Is there a simple way to change the default COM port an Uno connects to, without needing to change it every time I want modify my project?
Thanks in advance.

Nope. It's up to the PC to decide which com port to assign your USB.
I don't depend on the IDE to tell me what com ports go to which board- like you it's not unusual for me to have two or three boards plugged in at a time.

I keep the Windows Device Manager open and the com ports expanded. When I plug in a board, I just watch to see which new com port appears.


Maybe you can use an ESP01 to serve as a programmer via an IP address, I use it for a long time and it is much better than using a USB cable:

ESP-LINK: Wifi-Serial Bridge w/REST&MQTT

Program from Arduino IDE

Thanks. I can get around it by changing the COM port in Device Manager. It gives me a warning that the port I want to move to is already in use, but actually it is not as I would have disconnected that Uno before plugging in the new one.

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