Well well well. That is a blast from the past. I used to work at Videcom and have just talked to the designer of this unit. Unfortunately she cannot remember exactly how it worked. If you can post a photo of it (not here, this isn't a binary group) I can email this on and see if it jogs any memories. But my best guess is that you'll need to get hold of the manual or to talk to someone that remembers using it. Incidentally, where did you pick this up?
Picked it up on Ebay, it's a huge beast (mostly power supply). Interestingly I had a peek inside and the Eprom on the mainboard has an Elan sticker over the Window. Whether the two companies merged at some point I don't know - they both seem defunct now though.
Can't get it to talk to the PC via the serial port tried post of the common baud,parity, stop bit and handshake options in Hyperterm), the unit goes through a rather attractive self test on power up so if nothing else I have a heavyweight Christmas decoration.
Can you beg/borrow/steal an RS232 tester to plug into it, to see what lines it's lighting up? Since getting one of these little gadgets, RS232 unresponsiveness hasn't been a problem for me since I've always been able to find out whether Rx and Tx are reversed, or if hardware flow control is being a pain, or if (as was once the case) it's synchronous RS232! It's Just a bi-colour LED on each line so you can see what is driving what.
If you're in the London area, I can come over with my RS232 tester! :-)
The photo does bring back memories. This unit was originally just built to copy EPROMs, and it seems that (with the evidence of the Elan sticker) the programmer has undergone some further work (to make it hook up to a PC) since the original engineer worked on it.
The unit was made to duplicate EPROMs back in the days when Videcom actually manufactured terminals used (mainly) in airport check-in systems. Videcom stopped making real hardware several years ago. Their 'sister' company Access Keyboards
were probably the users of this programming equipment. Both companies still exist, and you could try an email to them. You never know, someone might still remember this unit.