[André Sarmento] needed to connect a computer to an RS-485 bus. 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.

Did it have a little adapter in the box? There was a time when if you bought a USB mouse, in the box was ... it may well have come with an adapter for a 9-pin RS232 serial port.

The DSX-USB Communications Interface is a simple yet rugged USB converter. This port powered device connects to any 2.0 USB Port through the supplied cable. The module provides an RS-232 output ...