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veovis
September 24th, 2017, 05:40 AM
Greetings,

I have been interested in the Creative CMS or Game Blaster cards for quite some time but since the cards are fairly rare I haven't been able to obtain one. I stumbled across the work by Tronix described here (http://www.vcfed.org/forum/showthread.php?47363-Creative-Music-System-(CMS)-Game-Blaster-compatible-replica) and saw that he had some success at building a clone of the CMS card.

Tronix had problems with a large amount of noise making it into the output of his card but this was likely due to the lack of a good ground plane and separation of the audio from the digital signals.

Since I haven't been able to find an actual CMS card I decided to build my own based on the work by Tronix and the Sergey's auto detection circuit. In the end, I modified Sergey's auto detection circuit because it allowed the card to respond to addresses that it really shouldn't respond to. While I was at it, I added a jumper to set the card's IO address anywhere from 210 through 260 like the original creative card.

I decided to use the same TEA2025 amplifier that Creative used on the Game Blaster cards. Based on the pictures of the card that I was able to find, it looks like the amplifier on Creative's card is very similar to the reference example in the TEA2025 datasheet so I used the capacitor values from the datasheet.

The result is what I hope is an accurate sounding clone that should have nearly 100% compatibility with the CMS / Game Blaster. Due to the problems that Tronix experienced, I decided to go straight to a 2 layer PCB design and tried to keep the analog signals as far as possible from the digital lines.

I got my prototype PCBs back from the fab last week and built one of them this weekend. The card is detected by the Creative testcard utility and the audio output appears to be quite good. There is a little bit of background noise in the output when the card is not playing but it is not objectionable. In fact the noise level is about the same as the background noise level of the Sound Blaster 16 that I have in the same system.

40935

One problem I encountered was I didn't have a 10k dual audio taper pot that was short enough to fit through the bracket once the card is installed in an ISA slot. So, I soldered 4 resistors in it's place to create a fixed output that is somewhere around line level. It looks a bit odd because the PCB footprint is for a pot but it works!

I think I may actually leave it that way because that way I can run the output of my clone card into the line in of another audio card to have both CMS and Sound Blaster support in the same system coming out the same set of speakers. I currently have my card set to address 220 and a SB 16 set to address 240 which appears to work fairly well.

I don't have a real CMS or Game Blaster card to compare to so I don't know how accurate the sound output is but it sounds pretty good to me.

Here are some quick recordings I made:

Creative Demo (https://soundcloud.com/user-532036888/creative-demo?in=user-532036888/sets/mus-1099-prototype)
Monkey Island (https://soundcloud.com/user-532036888/monkey-island?in=user-532036888/sets/mus-1099-prototype)



Compatibility appears to be very good. So far the card has worked in everything I have tried including Bubble Bobble which I understand doesn't normally work when using a Sound Blaster with the CMS chips.

The board layout and Eagle project files for my prototype is available here (https://github.com/gemedetpaps/MUS-1099) if anyone is interested.

Trixter
September 25th, 2017, 09:18 AM
Great project, and thanks for making the files and layout available!

veovis
September 25th, 2017, 09:32 AM
Great project, and thanks for making the files and layout available!

No problem, I think it is important to make things like this available so that the hardware can live on in one form or another.

Be warned, I am not an electronics expert by any means - just a hobbyist and I am sure my project files and PCB design reflect that. I am just pleased that the card actually works and so far I haven't found any major problems with it.

Scali
September 25th, 2017, 09:34 AM
I take it you had to order a certain minimum number of PCBs?
In which case, are you interested in selling a few to people such as myself, who may want to build their own clone (I already built the Lo-Tech Tandy card)?
Alternatively, I'd also be interested in one if you assemble it yourself.

PeterNC
September 25th, 2017, 10:19 AM
Looks great! I updated Wikipedia.

veovis
September 25th, 2017, 10:29 AM
I take it you had to order a certain minimum number of PCBs?
In which case, are you interested in selling a few to people such as myself, who may want to build their own clone (I already built the Lo-Tech Tandy card)?
Alternatively, I'd also be interested in one if you assemble it yourself.

I had to order 10 PCBs and I believe the fab sent me 12 or 13 boards so I certainly do have some spares that I can sell if people are interested.

Not sure what shipping will be to The Netherlands - I will have to get an estimate and get back to you.

All components are through-hole so the boards are quite easy to assemble. I used a socket for all ICs except for the amp because the datasheet specifically advises against using a socket for some reason (probably noise levels.)

I should have enough 74 series logic chips to build a few more boards but I don't have any more SAA1099 chips at the moment and I will need to find a pot that will fit on an ISA card for the volume control.

If there is enough interest in bare boards or assembled cards I am certainly willing to entertain the idea of doing a larger order of PCBs and components.

Scali
September 26th, 2017, 06:19 AM
Excellent... if you could put together a Bill-of-Materials, I suppose I could order everything required from eg mouser.com, except for the SAA1099 chips, which I can probably get off Ebay or such (it's where I got the SN76489/SN76496 chips for the Tandy card as well, cost next to nothing, from China).

veovis
September 26th, 2017, 07:55 AM
A brief parts list is available on Github (https://github.com/gemedetpaps/MUS-1099/blob/master/Parts.txt)

Mouser should have everything except for the TEA2025 amplifier and the SAA1099 chips. I got most of my parts from Tayda Electronics and the exact audio jack I used is available at http://www.taydaelectronics.com/3-5mm-low-profile-stereo-audio-jack.html although most any 3.5mm jack should work as long as the PCB footprint matches.

The TEA2025 and SAA1099 both should be available from multiple Chinese sellers. I got my SAA1099 chips from UTsource (https://www.utsource.net/) since in my experience they tend to use proper ESD-safe packaging and their prices are usually close to other Chinese sellers but of course eBay is an option as well. They probably have the TEA2025 as well although I got that from Tayda.

If you buy from UTSource, make sure the seller is listed as "UTSOURCE" because they do list items from other sellers on their website.

If anyone wants any of my spare PCBs, send me a PM. I am willing to sell them for $10 per board plus shipping (should be about $5 for those in the USA, more elsewhere.)

smbaker
September 26th, 2017, 04:39 PM
I may be interested in a bare PCB if you decide to sell just the PCBs. I like building things, and have a pile of existing 74XX chips from other projects.

chulofiasco
September 27th, 2017, 05:27 AM
I'd like a board and bits kit to assemble. It's relaxing.. lol

Xacalite
October 2nd, 2017, 05:27 PM
Nice project, indeed.
BTW: what software is there with CMS/GB support? I know of the following:

the stuff which came with the card, notably the *.cms files player
100 games listed in MobyGames: 99 from 1987-1992, and the modern Paku Paku
MIDI driver for Warcraft II (and maybe for other games using the same sound system)

Anything else? MIDI driver for Windows? Any demos?
And is it possible to tweak CMS to work as a DAC?
In the docs for GLX 2.12 I found "Future enhancements : SoundBlaster Stereo Support (that's not SB Pro, no typing error !)" - which would suggest using the CMS chips, but looks like it's never actually been made.

veovis
October 3rd, 2017, 02:19 AM
I don't think their are any Windows drivers or applications that use the CMS but Tronix has built a Miles Sound System driver for the CMS that allows it to be used in most games that use Miles audio (Warcraft II included). You can find more about it at this thread (http://www.vcfed.org/forum/showthread.php?47363-Creative-Music-System-(CMS)-Game-Blaster-compatible-replica&p=368871#post368871)

I doubt you will have much success using the CMS as a DAC - it really isn't designed for that. Creative has 2 demos that I know of that use the CMS and several song disks. Outside of that, support is mainly limited to the 100 or so games that support it.

However, for those games that do support it I find the CMS audio to be quite enjoyable - especially in games such as Silpheed and Thexder Firehawk. Yes, these games support the MT-32 and sound great with it, but the CMS soundtrack is closer to the PC-88 originals and is far more fitting in my opinion - it definitely has its own charm to it and is quite different from Adlib music.

Trixter
October 3rd, 2017, 07:25 AM
And is it possible to tweak CMS to work as a DAC?


Yes. I have an idea of how to do this; it's done the same way as it is on most platforms, where you trick a channel into producing a level waveform and then bit-bang the volume register. I believe I have code to do this, and if not, I think the Activision omnimusic driver played sampled audio through a CMS so I could disassemble that and poke around.

Speaking of which, here's a great write-up of games that support digitized audio on chips that were not designed for it: http://nerdlypleasures.blogspot.com/2014/07/pushing-limits-pc-sound-chip-digitized.html

Also, any games that used the omnimusic driver might play digitized audio on CMS. Confirmed list of games:

Activision's F-14 Tomcat
Activision's Ghostbusters II
Activision's Shanghai II: Dragon's Eye
Capstone's Bill and Ted's Excellent Adventure
Capstone's Trump Castle II
Infocom's BattleTech: The Crescent Hawks' Revenge
Interplay's Lord of the Rings: Vol. 1
Sega's Joe Montana Football

Unconfirmed list (I found "omnimusic" in the executables but never tested it):

./1992/LeatherGoddessesofPhobos_2_GasPumpGirlsMeetthePuls atingInconveniencefromPlanetX_1992__Activision_Inc .__Adventure_/MADE.EXE
./1992/Rodney'sFunscreen_1992__Activision_Inc.__Education al_/RODNEYS.EXE
./1991/TrumpCastleIIv1.1_1991__CapstoneSoftware__Simulati on_/TC2.EXE
./1991/Lots_o_$lot$_1991__CapstoneSoftware__Simulation_Ad don_/TC2.EXE
./1991/StarTrek_25Anniversary_Demo__1991__InterplayProduc tions_Inc.__Adventure_/DEMO1.EXE
./1991/StarTrek_25Anniversary_Demo__1991__InterplayProduc tions_Inc.__Adventure_/DEMO2.EXE

Finally, Tongue of the Fatman acts like it uses the omnimusic driver but I couldn't confirm that.


In the docs for GLX 2.12 I found "Future enhancements : SoundBlaster Stereo Support (that's not SB Pro, no typing error !)" - which would suggest using the CMS chips, but looks like it's never actually been made.

There was no later version of GLX, so that was never done. But yes, bit-banging the CMS chips, one channel for right and another for left, would have indeed worked. This would have required a lot more CPU power though, and the output quality would have been worse.

Trixter
October 7th, 2017, 12:50 PM
I doubt you will have much success using the CMS as a DAC - it really isn't designed for that.

Neither was the Adlib, but there are a few games that use it well as a DAC, such as Stunt Driver (in fact, the game runs faster if you choose Adlib instead of Sound Blaster, since it uses the Sound Blaster's byte-at-a-time DAC mode instead of DMA).


it definitely has its own charm to it and is quite different from Adlib music.

Being stereo definitely helps.

Two of the best CMS soundtracks I've heard are Times of Lore and Qix.

Scali
November 1st, 2017, 02:40 PM
One thing I'd like to ask about the parts list:
What tolerance % is recommended for the resistors?
I see you used light blue ones on your card, they are 1%?

veovis
November 2nd, 2017, 02:15 AM
5% resistors should be fine since that is what Creative appears to have used on the original cards.

I used 1% resistors on mine but that was simply because it is what I had in stock. There is nothing in the design that actually requires a high level of precision.

Scali
November 8th, 2017, 08:34 AM
Okay, I got most of the parts.
TEA2025 and SAA1099 are still underway. Also, I haven't managed to source a fitting volume pot yet.
I just put all the ICs and the resistor network on one of the cards. For the SAA1099s I used two sockets. I also put the 3.5mm jack on. It fits, but mine only has 3 of the 5 pins. The other 2 holes don't seem to be connected to anything on the PCB. Next stint will be the caps and resistors. Then I'll have to wait for the remaining parts to come in.

veovis
November 8th, 2017, 08:59 AM
The footprint for the 3.5mm jack has extra holes because the jack I used happened to have a built-in switch which is not used in this case. The jack you have should work fine unless the pinout of the jack happens to be different (which is doubtful, pinouts for these types of jacks appear to be pretty standard.)

When I designed the PCB I used a footprint for a volume pot that I thought would fit. However when I ordered the pot I discovered it was too tall to fit. I think a Bourns PTD90 series like the one at Mouser (https://www.mouser.com/ProductDetail/Bourns/PTD902-1025K-A103/?qs=sGAEpiMZZMtC25l1F4XBU4LIzrlRxKBZ%252bXQhywF%2f Fas%3d) will fit the PCB footprint and be short enough for an ISA slot but I haven't purchased one to test yet.

Scali
November 10th, 2017, 01:35 AM
The footprint for the 3.5mm jack has extra holes because the jack I used happened to have a built-in switch which is not used in this case. The jack you have should work fine unless the pinout of the jack happens to be different (which is doubtful, pinouts for these types of jacks appear to be pretty standard.)

Yea, there were a ton of different jack pinouts, and for this particular pinout, there were 6 models:
3, 4 and 5 pins, and of each variation, either with a threaded jack or not.
I got the 3-pin version, because the extra pins appeared to be for switching. I didn't think they'd actually leave off the pins though. I thought they'd still be on the jack body for extra support. But there's just two holes in the casing where the pins would be.
No big issue.


When I designed the PCB I used a footprint for a volume pot that I thought would fit. However when I ordered the pot I discovered it was too tall to fit. I think a Bourns PTD90 series like the one at Mouser (https://www.mouser.com/ProductDetail/Bourns/PTD902-1025K-A103/?qs=sGAEpiMZZMtC25l1F4XBU4LIzrlRxKBZ%252bXQhywF%2f Fas%3d) will fit the PCB footprint and be short enough for an ISA slot but I haven't purchased one to test yet.

I'm afraid not. I have a few Bourns PTD902 of 1k:
https://nl.mouser.com/Search/ProductDetail.aspx?R=PTD902-1015K-A102virtualkey65210000virtualkey652-PTD902-1015KA102
They should be the same size as the 10k ones. These have a far smaller pinout than the PCB footprint.
Perhaps an alternative is to get a chassis-mounted version of such smaller pots, mount it in the ISA bracket, and then run wires to the PCB.

Scali
November 24th, 2017, 09:51 AM
I'm happy to report that my SAA1099s and TEA2025s finally arrived. I put one card together, with some resistors to substitute for the missing volume pot.
I did a quick test, and it seemed to work! I started Leisure Suit Larry 3, and I could hear the music. It was very loud, noisy and distorted, but that's probably because my resistor-hack for the volume wasn't a very good one :)

I'll have to shop around for a proper pot, and then I can properly test it. Currently I'm not sure if the distortion came from the amp, speakers, or from the card itself.

Scali
December 7th, 2017, 12:42 PM
I've managed to install a 10k pot on it, hanging from a few wires. It's not pretty, but I can control the volume, and the distortion was probably coming from the speakers and/or the amp being too loud.
Initially I was missing some sounds, it seems, but I swapped the SAA1099s for some others, and now it seems perfect!
So either I have a dodgy SAA1099, or it wasn't seated in the socket properly. I'll have to do some more testing, but I want a pot that fits properly first :) I ordered some online, they should arrive any day now. Hopefully these will fit :)

veovis
December 7th, 2017, 01:30 PM
Glad you were able to get the card working and the distortion issues under control. If your SAA1099s came from eBay it is possible that they were pulled from other devices and it is certainly possible to end up with a bad chip that way - or it could just be a bad connection in the socket or a questionable solder joint somewhere as well.

Hopefully you can find a pot that fits within the height constraints of an ISA card/slot. If I had it to do over again, I would have made sure I had an appropriate sized pot on hand before getting the boards made.

Scali
December 8th, 2017, 07:07 AM
Well, the pots I got were indeed too high, so I ended up mounting them in reverse. Sadly, this also reverses the audio taper, so they're really touchy at low volume now. If I just went with linear I wouldn't have had that problem, heh.
Nevertheless, it works:

https://youtu.be/kxWg1z-yBl0

And yea, those Bourns PTD90 series would probably have been the perfect size. Perhaps you could update the PCB schematic so that the pinout matches to them? Then if anyone orders another batch, that problem is solved.

One thing I wonder though: where the heck did Creative and others get those 'dial' type pots they used on the Game/Sound Blaster cards? I could not find any of those anywhere.

Scali
December 9th, 2017, 05:12 AM
I did a bit of a hack, which turned out ok:
I took a smaller pot, used the front-middle pin through the PCB, and bent all the others so that they could be soldered on top of the PCB.
The result is actually quite nice, and the pot is now accessible from the back of the PC :)
42397
This is what I would recommend others to do as well.

Trixter
December 9th, 2017, 07:44 AM
Very nice!

Is the output stereo? Can't tell from the video.

veovis
December 9th, 2017, 08:57 AM
The output from the card is in stereo. It should be just like the original Creative card unless Creative did something odd like swap the left and right channels or something like that.

Scali
December 9th, 2017, 09:54 AM
Very nice!

Thanks! Veovis did a nice job on the PCB!


Is the output stereo? Can't tell from the video.

It sure is!
I am currently trying to code a routine to play PCM samples. If that works, you can get stereo digital playback from any SB 1.x/2.0 :)

Trixter
December 10th, 2017, 09:29 AM
I am currently trying to code a routine to play PCM samples. If that works, you can get stereo digital playback from any SB 1.x/2.0 :)

If you're successful, we should contact the author of Galaxy Player and try to get him to release the source so that we can complete it based on his promise.

Scali
December 16th, 2017, 10:30 AM
I have discovered some 'interesting' behaviour:
With the Game Blaster clone, my IBM Music Feature Card could no longer be detected.
Now, I know the detection routine for the IMFC works by writing a value to a latched register on the card, and reading it back to see if it 'stuck'.
So I tried doing that manually. I noticed that if I wrote 'FF' to it, it read back as '7F'. So apparently the top bit got 'eaten' somehow.

Now, the IMFC has a base address of 2A20, and this particular register is at 2A21h.
My Game Blaster clone was set to a base address of 220h, so it would use the range 220h-224h. If the card does not fully decode the address, then it may 'mirror' itself in the 2A20h-2A24h range as well. So it may be interfering with the IMFC, causing the issue I had.

So first I pulled the Game Blaster, and the IMFC was detected properly again: writing and reading FF was no problem.
Then I reconfigured the Game Blaster to a base address of 210h, and put it back in. Writing and reading FF was no problem... however, the second test is to write and read 0.
Doing this yielded 'E5' when reading back.

Any thoughts on this? I mean, is this actually a bug, or is the original Game Blaster designed like this? And do we want to fix this, or simply accept that it is what it is?
It would seem that most cards are in the 200-3FFh range of ports. The IMFC is actually the only card I've ever encountered to have an address like 2A20h (using 14 bits rather than just 10). Perhaps most cards treat any address bits above the 10th bit as 'don't care'?
There may be many other cards that have the same issues.

veovis
December 16th, 2017, 12:09 PM
What you are seeing does make sense. My clone only decodes up to A9 which allows for address up to 0x3FF which I believe is the official upper bound for expansion card IO addresses for IBM 5150 and 5160 PCs at least.

I didn't realize that decoding the other address lines may be necessary - especially since the few address decoding examples I could find only went up to A9. Decoding the other address bits would probably require adding a few more logic chips.

I don't think I have ever encountered a card that went beyond 0x399 before. It would be interesting if someone with an original Game Blaster or CMS could look at their card and see if the address lines above A9 (A10 through A19) are connected to anything. I would be surprised if they are but who knows.

Kazblox
December 16th, 2017, 03:21 PM
The Compaq Portable III uses I/O ports past 0x399 in order to configure the internal CGA daughterboard.

Scali
December 17th, 2017, 04:17 AM
What you are seeing does make sense. My clone only decodes up to A9 which allows for address up to 0x3FF which I believe is the official upper bound for expansion card IO addresses for IBM 5150 and 5160 PCs at least.

Yes, I've just looked through the manual of the 5150 here: http://minuszerodegrees.net/manuals/IBM_5150_Technical_Reference_6025005_AUG81.pdf
Eg on the Game Adapter part, they say that only A0-A9 are used (page 2-119).
They clarify that the card responds to IO addresses x'201', so that would be exactly what the Game Blaster clone does.
If you look eg at the Asynchronous Communications Adapter, the table on page 2-125 also only lists A0-A9.

A bit strange then, that IBM/Yamaha chose to use the address range of 2A20/2A30 for the Music Feature Card. It came out in 1987, and was at least meant to be used in 5160s, possibly 5150s as well.


I don't think I have ever encountered a card that went beyond 0x399 before. It would be interesting if someone with an original Game Blaster or CMS could look at their card and see if the address lines above A9 (A10 through A19) are connected to anything. I would be surprised if they are but who knows.

I agree. In fact, I have a Sound Blaster Pro 2.0. It would not surprise me if this card also clashed with the IBM Music Feature Card if I configure it to 220h. I will test that out sometime.

By the way, what I said above:

Then I reconfigured the Game Blaster to a base address of 210h, and put it back in. Writing and reading FF was no problem... however, the second test is to write and read 0.
Doing this yielded 'E5' when reading back.

I think this was my mistake. My detection routine did not reset the card first, so reading back the register was returning an error code, I believe.
I added a reset to my routine, and now it detects the card properly (writing and reading FF first, then writing and reading 0). I've tried it with the Game Blaster jumper in every position, from 210h to 260h, and only at 220h it didn't detect it.

Cloudschatze
December 18th, 2017, 10:31 AM
In fact, I have a Sound Blaster Pro 2.0. It would not surprise me if this card also clashed with the IBM Music Feature Card if I configure it to 220h. I will test that out sometime.

Ran into this issue some ten years ago. The limited address decoding of any Sound Blaster prior to the SB16 does result in conflict with an IMFC at 2A20h. Where I'd hoped to use a SBPro2 in a system with an IMFC, I ended-up having to use an AWE32 instead.

Scali
December 18th, 2017, 10:58 AM
Ran into this issue some ten years ago. The limited address decoding of any Sound Blaster prior to the SB16 does result in conflict with an IMFC at 2A20h. Where I'd hoped to use a SBPro2 in a system with an IMFC, I ended-up having to use an AWE32 instead.

Okay, thanks for confirming my suspicions! So it is safe to assume that the real Game Blaster works the same as well.

Why could you not use the SBPro2 at another address though? Is there a lot of software that is hardwired to 220h?
I used to have a GUS and an SBPro2 in a single system. The SBPro2 was at 220h and the GUS at 240h. I ran into some GUS software that was hardwired to 220h, so I ended up wiring up a switch to the base address jumpers on both cards. With a flick of the switch I could swap 220h and 240h on both cards. Then a simple batch-file would modify the BLASTER and other env settings, and re-run the GUS init software, and you were good to go.
I never actually tried to use the SBPro2 at 240h though. It was mainly reconfigured to 240h to get out of the way of the GUS when required.

Cloudschatze
December 18th, 2017, 12:24 PM
Several older titles/drivers are hard-coded for 220h. I imagine most of those could be patched though. The bigger issue was that I already had a Game Blaster card sitting at 240h in the same build. :)

Nowadays, a better solution might be to just patch Sierra's IMF drivers to operate at the alternate 2A30h address.

CarlosTex
January 7th, 2018, 05:11 AM
Patching Sierra's driver shouldn't be too hard, but i don't have an IMFC to try. It would be nice to also patch Music Construction Set for IMFC and the IMFC demonstration software.

I've made my 2018 year resolution to finally get an IMFC but that will be quite an ordeal.

I'm a bit disappointed to know the IMFC has trouble working with non PnP Sound Blasters but i'm not surprised. In fact, the original dual OPL2 Pro Audio Spectrum exhibits the same behaviour with SB, SBPro and non PnP SB16 ir other non-PnP SB clones. One of those cards installed and MVSOUND.SYS just fails to find the PAS.

My solution was to use a YMF-719E card. I would ask Scali and Cloudschatze to try any OPL3-SA card with the IMFC. To work with the Gameblaster patching might be the only solution.

About the Tandy Sound card: i tried it on my 286 and 386 and the card just works at the default C0h address. It didn't on my socket 7 PC but it has been working in all early AT systems i put it in.

Scali
January 7th, 2018, 05:36 AM
About the Tandy Sound card: i tried it on my 286 and 386 and the card just works at the default C0h address. It didn't on my socket 7 PC but it has been working in all early AT systems i put it in.

Well, the problem is not that the card won't work. The problem is that the writes to the C0h register also go to the second DMA controller. If any software would ever try to use the second DMA controller, it will probably break (worst thing would be if you used a 16-bit HDD controller, and your data would get corrupted).
You may be able to 'get away with it', because hardly anything ever uses the second DMA controller (most HDDs use CPU polling instead of DMA, I think 16-bit sample transfers to SB16 or newer is the main use of the second DMA controller in practice).

So the DMA controller may be in a totally confused state, but since nobody actually expects it to transfer any data, you don't notice.

CarlosTex
January 9th, 2018, 01:24 PM
Well that's the point, i doubt that using the lo tech Tandy Sound card on a 286,386 will present any problem, unless someone is using some special hardware that requires high DMA. Maybe problems will arise only with 486 and up with VLB and PCI controllers. I haven't tried on my 486 yet but IMO Tandy Sound is more suited to XT and 286.

In any case it is obvious why Tandy 1000 TL's are still XT class systems instead of AT, and also why Tandy had to change the address for the 3 voice chip.

What i see in all this is a complete lack of consistency in IBM's designs.

Scali
January 15th, 2018, 02:15 AM
In any case it is obvious why Tandy 1000 TL's are still XT class systems instead of AT, and also why Tandy had to change the address for the 3 voice chip.

Yea, and IBM's XT/286 is actually an AT class system... what a mess :)
I think Tandy did a good job of integrating PC and PCjr features though.


What i see in all this is a complete lack of consistency in IBM's designs.

Indeed, that was also the conclusion after debugging some issues on my PCjr: https://scalibq.wordpress.com/2018/01/06/more-pcjr-incompatibilities/
It's a miracle that all these PCs work as well as they do, really.

soviet9922
November 19th, 2018, 01:01 PM
Someone have an extra PCB from this project that like to sell ?

ZoomPicard
January 19th, 2019, 06:44 PM
I have put together what I think are the correct components for this build:
https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=1d22359016

At this point I can't confirm that these are all 100% correct, just my first stab at it. If anyone has any comments let me know

There are three parts I am ordering from UTSource. Sadly direct from UTSource they will only sell TEA2025 in packs of 10 so I am trying to buy from an alternative on that site (See Screenshot)

50716

I will report on my progress once everything has arrived and I have put the board together

Product Cost total including the PCB which I got from Ebay here:
https://www.ebay.com.au/itm/PCB-MUS1099-ISA-8-bit-sound-card/382704656883

Is around $103 AUS ($73 USD) for myself living in Australia. I am sure US based it would around $50-70 USD

ZoomPicard
February 4th, 2019, 01:42 AM
Warning don't order the whole mouser project above!

Actually discovered a few issues once I had ordered this from mouser

I would recommend before you order using that project you remove the surface mount versions of the following two chips and replace with straight through pin hole ones (DIP):
74LS138 x 2
74LS374 x 1

Since I live in Australia I have sourced both of these from a local supply instead

Also the audio connector is wrong in that order.
The guy who put the PCB board together decided to go with a really strange stereo audio which has 5 pin(!) connection to the PCB. Not that common to find vs a 3 pin version.

I finally sourced the type I needed from eBay
51041

Take a look at the top of the unit and it will have a weird spring based design inside with a transparent top

UTSource also failed me on finding a TEA2025 amplifier chip. They contacted me to say they could not find any TEA2025 16DIP only surface mount ones!

I cancelled that part but I am still waiting for them to send me:
74LS245
SAA1099 x 2

I went on eBay and purchased the requried TEA2025 16 DIP instead

Getting all the parts for this project is some what of a challenge as many of them simply don't want to sell DIP chips only the surface mount versions, something that will get increasingly difficult as time goes by