Creative Music System (CMS) / Game Blaster compatible replica

[Trixter]

So, beta-version of Miles CMS.ADV driver in attachment (with source code).

Basically I noticed all the same bugs you did and fixed them back in October.

Catching up on CMS support -- were later versions of this code ever released?

 

[Al Kossow]

Hello,

I read about Creative Music System (CMS) / Game Blaster at Great Hierophant blog. This sound card based on two Philips SAA1099 chips and looks easy to duplicate.

Unfortunately, they are a popular chip and forgeries abound, as Eric discovered recently
https://twitter.com/TubeTimeUS/status/1041859996902875137

 

[Trixter]

Forgeries, or just remarked? Eric's thread was confusing because, if they're fakes, why do they produce sound as normal?

 

[Al Kossow]

Forgeries, or just remarked?

Apparently, remarked.

 

[Tronix]

Catching up on CMS support -- were later versions of this code ever released?

I myself do not remember well. Probably the latest version is here : https://www.vogons.org/viewtopic.php?f=24&t=43553 (attachments at first post). Still very simple, without noise and envelope generators usage. Unfortunately, I am not good in MIDI-synth programming, sorry.

One user from the russian old-hardware forum trace the new PCB and recently I soldered it:


Digital noise still present, because SAA1099 has an open-collector PWM output, which we pull-up to +5V power rail and collect all the interference. So, i make new +5V analog path with help 78L05 linear regulator from +12V:


The interference is all gone! The sound immediately improved and became clear. Finaly replace TO-220 package with TO-92

 

[mfaircloth]

Are the changes in the above pics all that are needed? I've seen a pic online that also shows a resistor and a jumper wire on the back of the board as well.

 

[Thermalwrong]

I myself do not remember well. Probably the latest version is here : https://www.vogons.org/viewtopic.php?f=24&t=43553 (attachments at first post). Still very simple, without noise and envelope generators usage. Unfortunately, I am not good in MIDI-synth programming, sorry.

One user from the russian old-hardware forum trace the new PCB and recently I soldered it:


Digital noise still present, because SAA1099 has an open-collector PWM output, which we pull-up to +5V power rail and collect all the interference. So, i make new +5V analog path with help 78L05 linear regulator from +12V:


The interference is all gone! The sound immediately improved and became clear. Finaly replace TO-220 package with TO-92

Thank you for the pictures and the explanation, I have the same card and it's working great now :D
Using a TO-92 regulator like your last picture.

 

[Tronix]

Recently I thought - that if i take the source codes of SoftMPU, modify them a little so that there is internal processing of midi commands and output of frequency and octave to the hardware port of cms. I thought this would allow games like Doom or Duke3d to run with "general midi" device selected in the settings. So, here we are: https://github.com/Tronix286/softmpu - pre-alpha _experimental_ version of SoftMPU/CMS.

Run with such options:

softmpu.exe /mpu:330 /output:cms

This seems to work in most cases only with real-mode DOS games/applications. For example, it work with PX midi player with genmidi.adv driver, LOTUS game (terrible sound), Monkey Island with Roland (MONKEY.EXE r). Unfortunately, DOS4GW Doom and Duke3d can not initialize MPU401 port. As far as I understand, the problem is in the SoftMPU itself and I don't know what to do about it.

While playing with SoftMPU, I found one typo in the sources of Miles CMS drivers from first post. In CMS.INC procedure CmsSound() mixed voice_n and voice variable, only the voice_n variable should be used. So, new Miles CMS drivers (.ADV and .MDI) in attachment.

 

[Tronix]

I added auto detect for CMS port (210h - 260h) to Miles drivers and SoftMPU/CMS. Also i fix another stupied typo in SPKR.INC. And I create repo for Miles drivers, so no need ZIP archives anymore. You can download last version from:
https://github.com/Tronix286/AIL2
https://github.com/Tronix286/softmpu