How do I add a custom PID to the ftdi_sio  Linux COM port driver?

On your  Linux system,  open a terminal window and login as root (or use sudo). Enter the following:modprobe ftdi_sio  <ret> / echo VVVV PPPP > /sys/bus/usb-serial/drivers/ftdi_sio/new_id <ret> / …where VVVV is the USB Vendor ID (0403 for FTDI) and PPPP is the custom Product ID. Plug in the FTDI  device programmed with the desired PID,  and enter: dmesg | grep FTDI <ret> You should see confirmation that the device is recognized and assigned a COM port.This PID assignment will remain until the Linux system is rebooted.