USB comport on USB hub (CYUSB3304)

[aldoc_3474881]

Hi. I'm using the CYUSB3304 hub and two CP2102N  usb to serial ICs. These USB to serial devices are going to 2 different microcontrollers. Is it guaranteed that each USB to serial device will get the same COM port after plug-in and plug-out events? Meaning that if IC1 gets COM4 and IC2 gets COM5, next time I plug them in I get the same COM port assignment? I did a bit of testing, and the results seem to indicate so... But I'm wondering how? and is it guaranteed forever? Does the USB on DS1 get the first COM port and the USB on DS2 get the second COM port? 

Note: I already enabled the IgnoreSerialNumber for the USB to Serial Devices.

Thank you.

[Sananya_14 · Accepted solution]

Hello,

The COM port number is assigned by the host and depends on the VID, PID and serial number of the devices. So, if the devices have a fixed serial number, the host will assign the same number each time for the device but enabling the IgnoreSerialNumber will not guarantee that.

Best Regards,

Sananya