Communicating with 1756-RIO

Current system is PLC5/40 communicating with computer optimizer via KT card over channel 1B in adaptor mode. 1B configured for N39:0 thru N39:7 as discrete transfer output source and N39:8 thru N39:15 as discrete transfer input source.
PLC status info is passed to optimizer via N39:0 thru N39:7 and optimizer solution data is passed to PLC via N39:8 thru N39:15.
We are converting this system to a ControlLogix L72 and plan on using a 1756-RIO in adapter mode to communicate with the optimizer. I am unclear on how to configure the 1756-RIO to accomplish this task.

Is this a 1784-KTS, or an ordinary 1784-KT ?

Those cards go way back to the early 1980's and the most popular ones were the 1784-KT Series B (8-bit ISA style) and 1784-KTX (16-bit ISA style), then later the 1784-PKTX Series A and B (5V PCI, then Universal PCI).

The 1784-KTS was a RIO scanner version of the 1784-KTX.

If the Optimizer is really looking at the PLC-5 channel 1B as a RIO adapter, it will have a Rack/Group/Slot and Rack Size definition as well as integer data files associated with it.

My guess is that the PLC-5 is emulating one "Logical Rack" of 8 words. It's probably considered "Rack 0, Group 0".

Ken, you are correct. The PLC5, channel 1B is configured for Rack 1 Group 0 Full rack with N39:0 used for the discrete transfer output source and N39:8 as the discrete transfer input source.

Data placed in N39:0 thru N39:7 is read by the optimizer computer. The optimizer computer then writes the solution data into N39:8 thru N39:15 (8 input words and 8 output words).

What I want to know is can the 1756-RIO perform this task. I am trying to avoid the very expensive re-write of the communications software for the optimizer. Not certain but I think that the computer is using the old 1784 series not sure if it is KTX or KTS. I would hate to leave the old PLC5 processor in the system just to handle comm's but you do what you have to do