QL Soundcard?

[vanpeebles]

Speaking as someone who knows nothing about making hardware has anyone thought of creating some kind of QL soundcard (or even just an AY chip)? The sound in QL games is none exsistant so it would be pretty cool to have like a plug in soundchip (rom socket?) and some special versions of games.

[Dave]

*grins* I'm struggling right now with getting the video working properly on my 16-bit QL prototype, but adding an AY-3-8910 and simple address decoder would be trivial. I'll poke at it and see what I can come up with.

If anyone else gives me a schematic, I'll design the boards and produce them as an open source project.

[thorsinclair]

16 Bit QL prototype? Any further info on this or did I just miss sth?

[Mr_Navigator]

16 Bit QL prototype? Any further info on this or did I just miss sth?

ah look at Dave's other posts for a slightly clearer idea

[Dave]

It's not a formal "project" as such, but I am playing with a 68EC000 and some old QL components. I have the CPU and memory talking, and the ROMs load, but there is a video issue. The output is garbage - 95% working garbage, but garbage nonetheless.

If I can get to where I have a working QL minus sound, serial, microdrives, etc, I'll publish the schematics and make it into a shared, open project where we can add things in and maybe get to a simple, cheap replacement QL board that just happens to give a reasonable speed boost, like a gold card does.

Just playing with components and ideas...

[RWAP]

I agree - using the AY-3-8910 is not necessarily a good solution as the chips are not that easy to obtain (unless you go for Chinese clones). I have used the YM2149 instead in a couple of projects for the ZX81, but if possible, it would be better to use a different controller, maybe with more than 2 output channels, so you can have surround sound!

[Dave]

*laughs*

Personally, I have no use for sound generating chips, though I do have use for sound reproducing chips that are little more than an R-2R ladder, to convert samples. For that, no sound chip is required, really, in a minimalist system.

The problem there begins with many different systems running at different speeds. Then you start to desire a subsystem to read in the sample and play it out at a known rate, e.g. 48 kHz.

To me, the sensible Sinclairism would be to spoon the sound into the video system - to have sounds read and reproduced as part of the video interrupt cycle.

This does, of course, have the downside of making the QL slower and slower the more channels you want to play. I believe after about three channels, the QL would start going backwards.

[Dave]

Too much?