A simple converter can be sourced online, but the only thing he could find locally that was even close was a USB to RS-232 converter. He used that component to craft his own USB to RS-485 bridge.

It allow to send requests, either to get data, or send orders to the PLI. The RS-232 cable comes with the PLI, but you will probably need a USB to RS-232 adaptator. This projects uses this ...