I have a few IBM POS customer pole displays. They are 2x20 and are fluorescent and the part number is 61P5766. They have a four pin jack that is labeled 4 which I assume means it plugs into port 4 on the pos computer.I believe this display is used on the IBM 4694 POS system. I don't know if it uses RS-232 or RS-485. I have a few LTC485 tranceivers if it does use a RS-485 interface. I would like to be able to drive these displays from a PIC microcontroller or even a serial port on a PC but I have no idea what is required to communicate with it. I would greatly appreciate anyone having information on the interface, protocol and initialization.
Thank You, Bob