I haven't, but the problem described of the ISA BUS speed being too high is real. I guess it would be better to tweak this design and just feed the correct clock to the AY chips via a separate oscillator. I'm assuming it is a TTL clock signal.

I would imagine root42 would have done it by now, or maybe it's in his plans to do so.

That is one very, very basic board 😉

It's just begging for either a standalone oscillator or a configurable divider to allow it to run safely at 8MHz ISA bus.

According to the Hackaday writeup: " adding support for it in software and emulators is trivial". I've seen PicoMEM can emulate it, but Given Bank Street Music Writer isn't exactly on everybody's must-have list, anybody seen any software that has been modified to use it yet?

Only thing I don’t like is the chips standard I/O port is at port 300 and 302 (second AY chip). Port 300 is a common choice for hosting a second MPU-401 interface.

However patching software seems trivial indeed so port 302 (first) and 304 (second) would be a safe choice.

Also this board is an excellent candidate for a AIL 2 driver, with 6 voices it will sound much more complete than Tandy can do with only 3. Just cut out rhythm channel notes cause those won’t translate well into psg chips, and will for certain make the tunes sound well…out of tune.

matze79 wrote on 2025-09-13, 08:46:

did anyone try to build this Clone Board ?

https://github.com/Board-Folk/Mindscape_Music_Board

I didn't just try to build it, I built it, but mine is still untested and it still needs a bracket.
However, if you are looking for an emulator, I added Mindscape Music Board emulation code to PCem some time ago.
There is also a matching new code path in https://github.com/planet-x3/px3_ose/tree/obscure-hw to effectively redirect Tandy sound to the MMB.

Alright. Testing done.
The output is quite noisy, but the card works fine, overall.
I briefly switched the system to 7.16 MHz and 9.54 MHz mode and there were still no glitches, except for the expected higher pitch, but I do not want to risk damaging the PSG chips, so I quickly switched back to 4.77 MHz.

Modifying the card for a constant PSG clock speed turned out to be trivial:
You merely need to remove the 74LS74 clock divider flip-flop (U2) from its socket, bridge positions 6 and 8 and insert an appropriate CMOS oscillator with a frequency not too far away from 2.39 MHz.
This is apparently at least good enough for a turbo XT.

carlostex wrote on 2025-09-15, 17:11:

Only thing I don’t like is the chips standard I/O port is at port 300 and 302 (second AY chip). Port 300 is a common choice for hosting a second MPU-401 interface.

However patching software seems trivial indeed so port 302 (first) and 304 (second) would be a safe choice.

Also this board is an excellent candidate for a AIL 2 driver, with 6 voices it will sound much more complete than Tandy can do with only 3. Just cut out rhythm channel notes cause those won’t translate well into psg chips, and will for certain make the tunes sound well…out of tune.

I would then rather set the DIP switches for port 220h, which is the base port the Covox Sound Master normally uses.

Benedikt wrote on 2025-09-16, 16:41:

Modifying the card for a constant PSG clock speed turned out to be trivial:
You merely need to remove the 74LS74 clock divider flip-flop (U2) from its socket, bridge positions 6 and 8 and insert an appropriate CMOS oscillator with a frequency not too far away from 2.39 MHz.
This is apparently at least good enough for a turbo XT.

Good job, this is very useful information for clones in the future.

Benedikt wrote on 2025-09-16, 16:41:

I would then rather set the DIP switches for port 220h, which is the base port the Covox Sound Master normally uses.

Which options are available via the DIP switch? I would rather then not place it at 220h, unless no one wants to use a Sound Blaster Pro card, as sending PSG data to a port where an OPL chip is present will make the OPL squeal so much ears will want to commit suicide. This is the reason why I patched most CMS games to live in port 210h instead, so it could co-exist peacefully with a Sound Blaster Pro class card.

Best option would be, IMO, port 2C0h, as that is one of the available selections for the Covox Sound Master too. A Tandy card, will in that case be using port 1E0h, which is the default port used by Tandy for their VGA Tandy PC's with PSSJ.

carlostex wrote on 2025-09-16, 17:41:

Which options are available via the DIP switch? I would rather then not place it at 220h, unless no one wants to use a Sound Blaster Pro card, as sending PSG data to a port where an OPL chip is present will make the OPL squeal so much ears will want to commit suicide. This is the reason why I patched most CMS games to live in port 210h instead, so it could co-exist peacefully with a Sound Blaster Pro class card.

Best option would be, IMO, port 2C0h, as that is one of the available selections for the Covox Sound Master too. A Tandy card, will in that case be using port 1E0h, which is the default port used by Tandy for their VGA Tandy PC's with PSSJ.

The Mindscape Music Board is exceptionally flexible in that regard:
The DIP switch lets you freely choose the base address bits A2 to A9, i.e. you can theoretically set any arbitrary base address from 0 to 3fch in increments of 4.

I just patched the Ultima 6 driver for port 2F0h. I did it for 2F0h as it was tehe only way i could try on the PicoMEM. Port 300h is taken on my system. Sound does play...but result is far from ideal, feels like is playing only 90% right. But PicoMEM is emulation so i don't know where the problem might be.

@Benedikt
Can you set your Mindscape clone to port 2F0h and try? Just rename the file extension to DRV. Use the install program to choose Covox Sound Master, you can choose any port, it won't matter as i hardcoded the thing. So save your original file too.

EDIT: I should have tried the original driver first before patching, i just tried the original driver and changed the config to 2f0 and it worked the same. I thought it needed patching because Ian Romanick (from Youtube channel Tales of Weird stuff) said he tried to change the config file for port 300 and that did not work. I guess the program probably finds the 3 character and rejects the config. However it accepts 2F0h just fine.

I don't currently have an Ultima VI copy handy, but you could grab a CI build of PCem from the Actions tab of the GitHub repository and try it yourself.
My Mindscape Music Board emulation should be very accurate, except that it is hardwired to the correct clock speed.

By the way: When I said that the clock speed mod was trivial, this is what I meant:

carlostex wrote on 2025-09-15, 17:11:

Only thing I don’t like is the chips standard I/O port is at port 300 and 302 (second AY chip). Port 300 is a common choice for hosting a second MPU-401 interface.

Or for an Ethernet NIC...

Still, unfortunate address choices are common on very old sound solutions (Tandy...)

Benedikt wrote on 2025-09-17, 09:23:

I don't currently have an Ultima VI copy handy, but you could grab a CI build of PCem from the Actions tab of the GitHub repository and try it yourself.
My Mindscape Music Board emulation should be very accurate, except that it is hardwired to the correct clock speed.

OK, Ultima 6 involved? I'm in - will order hardware this evening 😉

By the way: When I said that the clock speed mod was trivial, this is what I meant:

oscillator_mod.jpg

That really is trivial, and helps a lot as my slowest XT is a bit too turbo for the original card.