Search found 226 matches

by Silvester
Fri Dec 04, 2020 9:10 am
Forum: Hardware
Topic: Serial port control question
Replies: 11
Views: 649

Re: Serial port control question

If you have Hermes you can use P20, P23 and P26 as inputs and/or outputs (see Hermes manual).

(IMHO you'd need to buffer them for output, pins are quasi-bidirectional: low is 300ohm to 0V, weak high is 50Kohm to +5V, strong high is 5Kohm to +5V for 272nS when set)
by Silvester
Fri Nov 20, 2020 1:20 pm
Forum: Software & Programming
Topic: MODPlay
Replies: 3
Views: 280

Re: MODPlay

Nice job. When I got my Q40 back in 1999 I was keen to try MOD playback, but the 20000/sec interrupt overhead put me off (IIRC at the time AD1848 chip was cheaper than DAC used :( ). Just received a YM2608 and YM2610 from China (quick 14 day delivery now!). They both contain AY type PSG, FM/OPN and ...
by Silvester
Fri Nov 20, 2020 12:16 pm
Forum: Hardware
Topic: QSound and QPrint Interface
Replies: 74
Views: 12139

Re: QSound and QPrint Interface

Sorry, but why bother? There is no software with which the board needs to be compatible with and any newly built solution should feature at least a real crystal for AY clock and two AY chips IMHO. I only contentplated this, mainly to repair my Qsound board. I have part done a Qsound Schematic, but ...
by Silvester
Tue Nov 10, 2020 4:01 pm
Forum: Hardware
Topic: QSound and QPrint Interface
Replies: 74
Views: 12139

Re: QSound and QPrint Interface

I did a rough schematic of QSound when PCB was posted. From what I saw it uses 750kHz E clock (60/40 duty). The AY data sheets specifies minimum 1MHz and 50/50 duty. But Bumble bees fly... As I wrote the QSound software calculates its frequencies for a 1.5Mhz base clock, so the E signal is only par...
by Silvester
Tue Nov 10, 2020 3:17 pm
Forum: Hardware
Topic: QSound and QPrint Interface
Replies: 74
Views: 12139

Re: QSound and QPrint Interface

mk79 wrote:Does anybody know how the clock for the AY chip is derived? I don't understand this from the posted PCB photos.

I did a rough schematic of QSound when PCB was posted. From what I saw it uses 750kHz E clock (60/40 duty). The AY data sheets specifies minimum 1MHz and 50/50 duty. But Bumble bees fly...
by Silvester
Tue Nov 10, 2020 2:22 pm
Forum: Hardware
Topic: QSound and QPrint Interface
Replies: 74
Views: 12139

Re: QSound and QPrint Interface

If you are one of the lucky ones with a SGC with PAR port...

Edit: I forgot to mention if you invoke AYplayer job without a file it will remove existing player and clear AY chip(s). Also, it will automatically work to a single or double chip interface.
by Silvester
Fri Mar 06, 2020 9:42 am
Forum: QL Emulation
Topic: How do you make a QL emulator?
Replies: 75
Views: 8968

Re: How do you make a QL emulator?

One of the saving graces of using an emulator I was glad of recently was being able to snapshot the QXL.WIN file and immediately recover stuff using a Linux hex editor (text search, cut & paste). I was swapping between an earlier working source file and new version to wring out bugs in some code...
by Silvester
Mon Feb 03, 2020 1:58 pm
Forum: Hardware
Topic: QL Eprom programmer
Replies: 38
Views: 9786

Re: QL Eprom programmer

Be nice to see how he programmed the GALs

Oh, and it would be a pity if all the work he must of done disappears :(
by Silvester
Mon Jan 20, 2020 1:35 pm
Forum: Hardware
Topic: QL-VGA
Replies: 33
Views: 4593

Re: QL-VGA

by Silvester
Fri Jan 17, 2020 9:47 am
Forum: Hardware
Topic: Qimi Mouse, a bit jumpy
Replies: 9
Views: 1179

Re: Qimi Mouse, a bit jumpy

No, still the same! I've had similar problems. The first (sudden movement of pointer to display extremes) was due to a flakey moulded 9D connector on the lead of the mouse - the socket clasps were too weak, so the connection was unreliable. The solution was to cut it off and use soldered socket. Th...