VOGONS


Reply 20 of 26, by Tronix

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After a year, a small update here. A user from one russian old-hardware forum trace the new PCB and recently I soldered it. Started checking without an amplifier:
P90713-200103.jpg

Digital f***n 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, as is done in many sound cards:
P90811-125954.jpg

The interference is all gone! The sound immediately improved and became clear. Finaly, replace 78L05 TO-220 package with TO-92 and mount ampliefier. Sound quality still good without noise. Waiting for variable 10k resistor....
P90901-075436.jpg

Last edited by Tronix on 2019-09-23, 04:02. Edited 1 time in total.

Reply 21 of 26, by digger

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Great job!

We can't have enough retro sound card projects going on. 😀 I'll continue following your progress with great interest.

Reply 22 of 26, by Fagear

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Tronix hello. I've implemented your circuit in "CMS" debug block for FMonster.
I can send you blank debug board if you are interested.

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New BIG soundcard: FMonster.
Covox Sound Master replica
Innovation SSI-2001 replica & DuoSID.
My audio/video collection.

Reply 23 of 26, by maxtherabbit

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Tronix wrote on 2019-09-22, 19:16:
After a year, a small update here. A user from one russian old-hardware forum trace the new PCB and recently I soldered it. Star […]
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After a year, a small update here. A user from one russian old-hardware forum trace the new PCB and recently I soldered it. Started checking without an amplifier:
P90713-200103.jpg

Digital f***n 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, as is done in many sound cards:
P90811-125954.jpg

The interference is all gone! The sound immediately improved and became clear. Finaly, replace 78L05 TO-220 package with TO-92 and mount ampliefier. Sound quality still good without noise. Waiting for variable 10k resistor....
P90901-075436.jpg

Is this project still alive? Are the EDA files for the board shared publicly somewhere?

Reply 24 of 26, by Tronix

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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 _test_ 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). 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.

Reply 25 of 26, by Tronix

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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

Reply 26 of 26, by digger

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Tronix wrote on 2021-02-27, 15:02:

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

Wow! Nice work. And that's a clever trick to use SoftMPU as a way to get many more games to output music through a CMS/Game Blaster.

Has this also been done yet for the Innovation SSI-2001 card? (It's a PC sound card with a Commodore SID chip that saw very little support in games back in the day, even less than CMS.)