DSC PC-Link Connector pinout diagram @ pinouts Connect it so that the red wire is directly beside the 'SO' printed on the circuit board. You will also need the DSC software. This will not work with just a ordinary comm. program. Wire colors at the header are immaterial since the PC-LINK is sold as a small circuit board with a female header, and any other implementation could use arbitrary15/19(19) Communication Tutorial - PC-Link - DLS5 Wiki - dlshelp The PC-Link connection method is a way of directly connecting to the panel using a physical cable (available through your distributor) from the panel’s 4 pin PC-Link header directly on board to a serial port on your computer or by using a USB-to-Serial adapter (Recommended model: Keyspan USA19HS).