Carbonboy,
are you sure that it is an SLC5/05 ?
The AIC is used for DH485 type of network.
The SLC5/05 CPU has an Ethernet port (ch1) and a serial port (ch0).
The SLC5/03 CPU has a DH485 port (ch1) and a serial port (ch0).
It is possible to set up the serial port on either model to use the DH485 protocol, but it is most common to use the DF1 protocol.
If ch0 is set up for DF1 protocol, all you need for programming your SLC5/05 or SLC5/03 is a 9-pin nullmodem cable.
Description of cable:
pin 5 to pin 5
pin 2 to pin 3
pin 3 to pin 2
Of course, if you do have an SLC5/05, then you can also connect to it via ethernet.