RS-232, Sensor, MX-850 Cable and IR Pinout Information


Notes About RS-232 Cables:

Many custom installers who use the URC RS-232 Controllers, run into the age old question of “Which pin number is Transmit (TX) and Receiver (RX)?”

When using RS232 it is important to know certain facts before connecting to a component.


  1. Some RS-232 controlled components require a Male DB9, while others require a Female DB9. These cables can be extended up to 30 feet and provide good results up to a 9600 baud rate using a cable of at least 16 gauge two conductor shielded wire.
  1. The TX and RX Pins are labeled from the URC side. When connecting TX from the MSC-400 it should connect to RX on the component side.
  2. Both RS232 Cables included with the MSC-400, RS-232M and RS-232F, are pre-wired to perform the null modem swap for you. IF you make your own cable, make sure to check the component manufacturers specifications for TX, RX and Ground pinouts.
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  • Excelent Help. Thanks Nice People of URC. Love It.!!!!