MiniBus™ Digital Databus System The Software Proprietary software is part of the system. To anyone familiar with Windows, it's fairly intuitive. It provides a broad array of switching options. You will need a RS232 to RS-485 standard converter cable assembly to connect computer to PDM. The software also programs the outputs: 1. One switch controls one output 2. One switch controls multiple outputs 3. Multiple switches control the same output.