The Sinclair QL Forum

Also worth a good look :

http://www.kbdbabel.org/

This pdf has some great info for ps/2 / AT keyboard and how it works: https://stardot.org.uk/forums/download/file.php?id=16103&sid=ee455101baf4ad5f2400aa442fe09dab This is from the following article: https://stardot.org.uk/forums/viewtopic.php?t=9461 Attempting to get a PS/2 keyboard from origin...

Not sure - but with a 150pf capacitor in there it was quasi stable, with 47pf it is rock solid with repeatable results. 2nd back of memory was down to pin14 on the D1 RAM not being soldered - time for another eye test - but 2 joints out of a couple of hundred isn't bad. ordered a new reset switch (d...

Thank you Vitaliy, Not sure what value I put in there - it was a low value - but I will make sure it is 47Pf. I also need to replace my reset switch as the original QL one I've used is not playing well, they are such a poor design. What switch part did you use in your design for the reset switch? Da...

Thanks Marcus - I am using a 'D' variant at 15ns - I have some 'A' variants at 25ns coming my way in the next few days - I will try again. Symptoms with the D are a bit odd! 1488 chip got a bit warm - but it could be a bad one - running tests without that in place Memory detected by Minerva on power...

Has anyone programmed a GAL 16V8 with the JED code that was published (I think it's in the distribution and also on Dilwyns site too).

I noted the comment about using a slower GAL - got some on order - but was interested if anyone had done this and what was the result ?

I would probably start with an existing PS/2 keyboard and see if the micro in it could work with the QL matrix as it already does the job of scanning keys. Especially if you have the sourcecode, that sounds like a good idea. Or get in touch with those QLers who already worked on similar projects. I...

I was coming at that from the other direction - taking a PS/2 feed and the column inputs from existing IPC to generate 8 bit 'scanned key code' - it sort of worked, but was easily confused by keystroke combos that have to be taken into account, and virtually all the extra goodies from the ps/2 keybo...

unless you go entirely 3.3v, but then you sacrifice any compatibility with original hardware

The hardest thing here is trying to find those keyboard tail connectors - those particular sizes seem the hardest to source... TME in Poland have them. https://www.tme.eu/en/katalog/connectors-ffc-fpc-2-54mm_112938/?visible_params=412%2C2%2C6%2C135%2C419%2C413%2C11%2C1247%2C22%2C32%2C425%2C2555&...