I recently installed VisiON on my newly-acquired IBM PS/2 Model 30, which has an 8 bit ISA architecture and should be fully XT-compatible. The 20MB hard drive is formatted with two partitions (!) so I can have FAT 12, which VisiON needs. I was also lucky enough to have an old 25 pin serial mouse, which works perfectly in VisiON. So you'd think all was well and it should work! Well, it does work perfectly until I touch the keyboard. Then the entire system freezes. I can tour round every part of VisiON, starting up programs, minimising them, and closing them, and I can scroll through all the text windows, as long as I only ever use the mouse, never the keyboard. Even if I exit from VisiON using the mouse and get back into DOS, the problem remains. If I touch the keyboard the system freezes instantly. However if I avoid VisiON when booting up and go straight to GEM Desktop instead, there is no problem and the keyboard is working OK. Also, all other DOS programs run OK as long as VisiON has not been loaded and then closed. Might it even be a problem with IBM PC DOS 5.0?

Hi

I don't know the program - VisiOn, but you mention indirectly - requirements of XT compatibility.

Its been too long since I worked on an XT system or latter AT systems, but I remember keyboards used to have a compatibility switch. ie you selected AT or XT, I think you could change this on the fly, but its all a distant memory for me. Most swithches were underneath.

Hope you still have an older type keyboard around to see what I mean.

Hi anenefan,
yes, I have an XT keyboard with the X/A switch, but the IBM PS/2 works perfectly in DOS with the cheap plastic modern keyboard I put on it, so it probably isn't that. VisiON is an early Windows-style interface for DOS, released in 1983. The only part of the software that's XT specific is the Graph program. I suspect it's to do with hardware and driver conflicts. Apparently VisiON has it's own keyboard controller driver, which causes a problem with that of DOS, or so it would seem. I just wondered if anyone else had tried out VisiON on an PS/2 8086 system and found similar problems.

Hi

Many programs worked closer with the keyboard controller chip than others esp to capture special key sequences. I know your keyboard would work mostly, but I was interested in how the xt mode keyboard performed in VisiON.

I dug around a bit on the net and found this informative link.
Keyboard data link

Pc-Guide simpler explanation

Hi Anenefan,
I've looked at these two pages, and they are a little too technically intense for me at this time of night, but I shall try the XT keyboard soon (the PS/2 is currently shelved until further notice) and see how it performs. I also wondered if there may have been BIOS settings in the PS/2 that could specify keyboard controller usage... but I have no idea how to program the BIOS on a PS/2.

I've tried the XT keyboard through a DIN - PS/2 adapter and set at XT it said "keyboard error" on boot up. Set to AT the system refused to recognise the F1 key (the clock isn't set and requires me to press F1 at boot up), so I couldn't test it further. The F1 key may be stuck as it is an old keyboard and when I got it only half the keys worked. But I found another cheap modern keyboard and tried it, with the same results. If I go into DOS Edit, I can type perfectly, but if I go into VisiON, the whole system freezes the instant I touch a key. So the XT keyboard will not work on a PS/2. Oh well, it was worth a try!
It must be just yet another typical 1980s hardware / software incompatibility!