Allen Bradley serial port utliizes their DF1 serial protocol. Scadapack serial ports use modbus rtu serial protocol. Telepace is a ladder programming package for Scadapack units made by control microsystems. You do not state which Allen Bradley plc you are using. I assume one of the RSlogix (5,500 or 5000) packages will work to program it. If you have an ifix software package, it runs a driver to get data from the plc. If it is connected to a serial port on the Scadpack, I would assume the ifix MBR driver (serial modbus rtu) is being used. In order for you to connect any device to a serial connection on the Allen Bradley, Scadapack or ifix workstation, it will have to talk the specific protocol native to that device. And either you device or the plc will need to be programmed to transfer data.