Checking back in. Finally got the opportunity to plug into the controller. Not much luck though. Any operations in visilogic to try to upload or even things like get hardware info, etc return an error. Watching from info mode, COM1 does switch to PCOM, 9600,n,8,1 whenever the laptop is trying to talk to it, but apparently is not responding in kind. The cable seems to be good, as I can see MODBUS traffic in realterm. Is this bland error the expected behavior if the PLC is locked down?
Again, thanks for any assistance.