The serial programming cable is an accessory for the Terxon MX. With the serial programming cable, you can easily connect your PC to the Terxon MX in order to configure the alarm system. The connection is made to the serial interface (COM port) of your PC or laptop. If no serial port is available, you can also use the USB adapter for Terxon MX (AZ5107) to connect the serial programming cable. The software required for programming can be downloaded free of charge from our website.