I remember asking Gemini000 about the DOSBox Tandy emulation when he did a Tandy video. He said that it sounds just like the real thing.

A tandy sound card would be awesome! I like the idea, but no clue how to implement it 😒

Isn't it essentially the Sega Master System's sound chip with some glue logic?

http://en.wikipedia.org/wiki/Texas_Instruments_SN76489

(Though it appears that Sega's implementation was slightly different.)

http://queststudios.com/smf/index.php/topic,2264.0.html

Suggests it might not be so easy, apparently the Tandy sound chip uses an IO port that conflicts with 16-bit DMA on 386 and above.

But someone also mentioned you could write a TSR to get around that?

I had a Tandy 1000TX wayyyy back which had the Tandy sound along with a 286. But the TX was a 286 on an XT platform so I guess that's why it worked?

Beg-pardon, that should have been "386 and above", a critical typo! 😖

The user BlueMax at QuestStudios mentions that his system is a 1000RSX, which is a 386SX 25MHz.

retro games 100 wrote:

Could it be done? Not owning a PC jr or Tandy machine, is there any other way of experiencing that Tandy sound, other than software emulation on a modern machine?

Wouldn't you also have to use software to bring a modern machine down to PC Jr or Tandy speeds? Not to mention there's the problem of replicating the Tandy graphics hardware. Recreating the sound hardware seems rather pointless if you have to recreate most of the rest of the computer to actually run Tandy/PC Jr software as it once did.

Besides, were there really that many games that made use of that sound hardware?

Jorpho wrote:

retro games 100 wrote:

Could it be done? Not owning a PC jr or Tandy machine, is there any other way of experiencing that Tandy sound, other than software emulation on a modern machine?

Wouldn't you also have to use software to bring a modern machine down to PC Jr or Tandy speeds? Not to mention there's the problem of replicating the Tandy graphics hardware. Recreating the sound hardware seems rather pointless if you have to recreate most of the rest of the computer to actually run Tandy/PC Jr software as it once did.

Besides, were there really that many games that made use of that sound hardware?

In my o.p., when I said "...on a modern machine?", I didn't mean that the "Tandy clone device" would reside in it.

I've only just realised that there are two types of Tandy sound. There's a 3-voice speaker system, and also something called a Tandy DAC, which seems to be similar to a covox device. How does a 3-voice speaker system work, roughly? What does it look like? - does it look similar to a PC "beep" speaker?

retro games 100 wrote:

Could it be done? Not owning a PC jr or Tandy machine, is there any other way of experiencing that Tandy sound, other than software emulation on a modern machine? IMHO, I think a project like this would be more important, than for instance attempting to make an Ad Lib clone card. However, it may be impossible, which would be inconvenient. 😉

It MIGHT be doable, however there is a caveat... a big one... many games that utilized Tandy sound also expect to do the Tandy enhanced CGA graphics mode which is exclusive to Tandy 1000 machines and no graphics card ever supported this special enhanced CGA graphics mode either, it was Tandy exclusive. The Tandy 1000RLX utilized VGA and the later Tandy games supported VGA along with Tandy Sound, however by then AdLib and Soundblaster were the industry standard.

The drivers for it would have to somehow trick the "enhanced CGA" games to think it's tapping into actual Tandy graphics hardware before the sound will even work, if it'll even work which is doubtful because of other factors which I seem to have forgotten at the moment.

EDIT: Seems that, Great Hierophant, below, has outlined the "other factors" which I mentioned.

I see. Are all of the various Tandy 1000 models fully backwards compatible? For instance, if you were to test a more modern Tandy 1000 model, for example the RLX or RSX, would it play really ancient Tandy games OK, using its VGA output? Would its VGA output be able to display the older Tandy "enhanced CGA" graphics OK, or would there be problems?

Honestly, this may be more trouble than its worth.

Most games expect one of several Tandy-specific things :

Tandy sound to be located at I/O 60H. True AT systems have the 2nd DMA controller at that I/O. All the 286 based Tandy 1000s, including the TX, TL, TL/2, TL/3, RLX do not have 16-bit ISA slots or a 2nd DMA controller. The RSX (1991) and later machines relocated it to 1F0H if I recall correctly. But most games only support 60H.

Tandy graphics, which no graphics card has ever supported. Some games also use IRQ 2 to detect vertical blank, which can cause conflicts.

BIOS signature, usually by finding the ASCII "TANDY" in it.

Ah, I see. Excellent advice - much appreciated. So it looks highly unlikely that a "3rd party" Tandy sound clone component card could be made to work successfully with the games that look for Tandy specific hardware. Oh well.

If I find an old Tandy 1000 machine, I wonder if I can buy one of those EGA to VGA converter gadgets found on ebay, and make it send the output to my VGA LCD?

retro games 100 wrote:

Ah, I see. Excellent advice - much appreciated. So it looks highly unlikely that a "3rd party" Tandy sound clone component card could be made to work successfully with the games that look for Tandy specific hardware. Oh well.

If I find an old Tandy 1000 machine, I wonder if I can buy one of those EGA to VGA converter gadgets found on ebay, and make it send the output to my VGA LCD?

You would be better off buying a VGA card that can work in an 8-bit slot, just don't buy a 1000/A/HD/EX/HX. Those EGA to VGA converters convert analog signals and CGA/TGA/EGA are digital signals.

Port 60h is the keyboard interface 😉

0xC0 is the conflicting DMA controller.

Could you not write a driver to intercept all of these various calls accordingly; that is, one to redirect audio to a card, one to emulate BIOS strings, one to juggle address incompatibilities and one to emulate the graphics mode and render it to a VGA screen? Or you could possibly emulate some of the hardware in an FGPA?

Sorry if this sounds preposterous, I'm a noob when it comes to what you can do with the hardware 😵

RichB93 wrote:

Could you not write a driver to intercept all of these various calls accordingly; that is, one to redirect audio to a card, one to emulate BIOS strings, one to juggle address incompatibilities and one to emulate the graphics mode and render it to a VGA screen? Or you could possibly emulate some of the hardware in an FGPA?

Why, exactly, would you go through that kind of trouble when you can just use DOSBox?

I don't know who would (I certainly wouldn't) but it's an idea 🤣

Maybe have a look at http://www.oldskool.org/pc/tand-em/

h-a-l-9000 wrote:

Maybe have a look at http://www.oldskool.org/pc/tand-em/

I would like to try this, but the instructions tell you to dump a .ROM file from an actual Tandy 1000 machine. Unfortunately, I don't have one. I searched online and I see that I am too late to acquire a .ROM file from demonlord's "retrograde station" website, because that website no longer contains any Tandy .ROM downloads.