The Sinclair QL Forum

The computers in the days of the Transputer could only ever be the simple VDU like human interface. Having seen in Linux, when I was looking for a graphics driver, there are capabilities to program GPUs I can't see the point in experimenting with 4 Picos when there are thousands of CPUs on a GPU. No...

A little thought for Christmas. I always wanted a Transputer, Even if I had to learn Occam to program it. :D The penny just dropped why the transputer was effectively taken out of the hands of the common people apart from its commercial bashing capability of the Intel and AMD complex chips. Back in ...

mk79 wrote: ↑Wed Dec 14, 2022 8:33 amSMSQ/E I didn't know it was pronounces "sam-squee"

I thought that was right. What is it called then?
Perhaps smmslashqey?

I am assuming you're measuring when the QL is idle and no program running. Then the only thing I can imagine is that you're seeing when the QL polls the 8049 for keys - That should happen every 1/50s or multiples of that and would keep the 8049 busy for a short time. But "a few seconds" i...

Then I would suggest not replacing the entire 8049 to avoid headaches, and continue your early plan with the keyboard with the same matrix layout as a QL. Now Tofro has made me realise the key scanning is working & I have done the code for the PIC I shall continue to fit it to the two QL matrix...

Plenty of info in the QL Service Manual, QL manual (KEYROW, BEEP), QDOS Technical Guide (trap #1 D0=$11 lists the supported/used commands), 8049 QL firmware disassembly, Mister QL sources (for ZX8302-8049 communication). You just described my problem & why I just lost the will to live. It would...

Without a membrane plugged in, I doubt you can measure anything useful (Except on Pin 9, as that is the only one without a diode.) Thanks for pointing out pin 9 has no diode and I am a dipstick for measuring floating pins. :lol: I have the scope the other side of the diodes so the 8049 can't really...

tofro wrote: ↑Mon Dec 12, 2022 12:28 pmPin 1, 2, 9 of what?

The 9 pin scan lines of the QL keyboard matrix without the membrane plugged in.

Since I had no pointers to the required info I stuck a scope on the key scan signals and it looks like my QL is dying of old age. :( Here are pictures of pin 1,2 & 9 where 9 is the only one that looks like what I would expect. The key scanning looks duff to me any comments? Note the order of the...

More stupid questions that someone can probably answer off the top of their head. How long does a QL keyboard key have to be present to register and how long is a scan line on for? All this is so I can get a simple serial or SPI link from the above keyboard to QL.