If you are connecting to the 5/04 via CH. 0 (serial port), and it has been configured for DF1 (RS-232 null-modem), use the DF1 driver and a 1747-CP3 or a standard null-modem cable. If CH.0 has been configured for DH-485, use the 1747-PIC/AIC+ driver and the same cable(s) listed above. If you are connecting via CH. 1 (DH+), you need a 1784-PCMK card (laptop) or 1784-PKTX card (desktop). You would then use the 1784-KT, KTX, PKTX, PCMK driver in RSLinx.