Assigning laptop's serial ports to specific motor drivers

I am working with an omni-directional robot and I have two of your motor drivers (both AX2850) installed to control four motors. I was wondering if there is a way of communicating with the motor drivers to find out the serial numbers, which I can use to identify serial ports on my laptop.

This is easily done installing two serial ports on the PC (example Comm1 and Comm2) and connecting Comm1 to a controller and Comm2 to the other controller.
In this way a command like "send comm1 strind" will only go to a specific controller, and "send comm2 strng) will go to the other controller.