The Sinclair QL Forum

tofro wrote:Afaik it was one single interface, providing the sound through an AY chip and in addition had a parallel printer port. It did advertise a printer buffer, but whether that was using QL main memory or came with its own buffer, I do not know.

Tobias

Yes, one board. And I do not believe, that Jochen has re-invented the wheel, so my have taken a few things, TT has managed for PAR on an SQB.

One version of the AY sound chip has a parallel port, so it is likely the chip was used to provide both functions with some help from glue "TTL" logic chips.

Mark

Any updates Paul?

Short: No
Long:
I am currently waiting for a Qsound from Derek.
When he finds the time to send it to me I will analyse it and begin thinking about possibilities for a reconstruction.
I have no answer from the copyright owner.
I have no hints that any Qsound compatible software might exist.
Any help or hint is welcome.
kind regards Paul

I know about the very past times, that Andreas has a very long way....

Gah! Fingers crossed!

Paul,

IMHO by far the best place for new sound board is ROM port. To prevent access to sound chip conflicting with internal QL-SD etc you could use the same trick Miracle did with their hard disk interface. Use discriminator circuit which only pages in when 8 consecutive fast reads are done. Miracle use MOVEM.L $0,A0-A1, anything else is rejected. See my circuit http://www.dilwyn.me.uk/docs/hardware/QLperip.zip

Since any access to sound chip will be done under poll task it shouldn't upset QL-SD. As long as $FEE0-$FFFF is avoided for QL-SD hardware, sound chip could be written by reading $C000-$C100 (register/data ports) when paged in.

Shared access to sound chip should be through driver. Best driven using Music Tracker style commands (ie. envelopes/ornaments predefined) so just require note data sent. The driver could also have access to library of sounds (zaps/explosions/etc) which would just need command byte sent to driver channel. QSound used strings of data like ZX PLAY; a bit cumbersome and limiting (echoed by QLWorld review of QSound Jan 1987).

I wouldn't bother with firmware in EPROM, it would hinder development. Once the hardware is done it would be trivial to write background AY play routine and simple register access (through poll task). The driver could come later (even a full Tracker).

The old sound chips are now very cheap from China (NOS). It'd be good to have QL sound with both an AY-3-891x and SAA1099. Both can also do crude 4-bit sample playback, but if you use AY-3-8910 the two 8 bit ports could do stereo DAC (albeit hogging CPU for small samples).

Windows/Linux libraries exist for sound chips so the emulators could (in theory) support same driver.

Perhaps of limited interest but here's a device independent MIDI file player.

You can even open a PIPE to basic and drive your own sound chip or BEEPer. With the MNET driver you can even play a real instrument.

I have seen that somebody bought a QSOUND interface from TTurner35 in michigan via Ebay on 20.12.2016.
Is the buyer here somewhere and willing to contact me?
If anybody else has a QSOUND, no matter if working or not, I would like to borrow it for a short period of time, maybe two weeks, in order to take the schematic and read the ROM content.

Kind regards
Paul

I have purchased the QSound/QPrint interface. I will be happy to assist.