Yes its an ESS 1688 IRQ is 2 DMA is 0 Port is 220 but I cant change the port in ESSCFG is there some way to disable the card in the config? I was previously on an old firmware that didnt have soundblaster support. The games ive bern trying to run are Doom and Duke 3D.

NeoG_ wrote on 2025-06-24, 22:56:

I have an ES1869 with a PicoGUS and can run it is SB mode next to the ESS card without lockups - You mentioned the port and IRQ […]
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swisstoni wrote on 2025-06-24, 17:27:

Thanks for the new firmware update which flashed fine. My system has an ESS1688 integrated on the motherboard ive changed the port and IRQ in software so it doesnt clash with the Picogus.

I have an ES1869 with a PicoGUS and can run it is SB mode next to the ESS card without lockups - You mentioned the port and IRQ but what about the DMA? Can you list what resources each card is set to use?

Was it working with the older firmware, which game is it? I can test it on my system as well

swisstoni wrote on 2025-06-24, 17:27:

Also when mounting isos if you have a physical cd drive in your system what drive letter would the iso be?

Drive letters for CD-ROM drives in DOS are controlled by MSCDEX, you supply it multiple /D:<devicename> parameters and they are assigned letters in that order starting with the first free letter. You can also override the drive letter for each drive using /L:<letter> /D:<devicename>

swisstoni wrote on 2025-06-25, 09:33:

Yes its an ESS 1688 IRQ is 2 DMA is 0 Port is 220 but I cant change the port in ESSCFG is there some way to disable the card in the config? I was previously on an old firmware that didnt have soundblaster support. The games ive bern trying to run are Doom and Duke 3D.

A few things - Since you were on single firmware before things have changed slightly. The PicoGUS now has all the firmwares rolled into one package and the default mode is soundblaster+cdrom but you can change this any time using "PGUSINIT /mode something".

E.G. if you were using the MPU401 firmware before, you would use "PGUSINIT /mode mpu". If you want to have the card start in that mode automatically each start/reset, use pgusinit /save to save the current mode to flash and it will default to whatever mode is currently set when you save.

A full list of modes is available here:
https://github.com/polpo/picogus/wiki/Configu … ng-your-PicoGUS

The ES1688 is not a PnP (that I know of) card so it's either set through the BIOS settings if it's integrated onto the motherboard or set via jumpers on the card if it's an ISA card. But it sounds like you just want the PicoGUS to stop responding as a soundblaster on port 220 which you can do by swapping modes as mentioned to disable soundblaster emulation.

Thanks for replying im going to have to look into disabling the ESS as its integrated on the motherboard. Im actually looking to disable the ESS and use the Soundblaster emulation on the Picogus.

NeoG_ wrote on 2025-06-25, 10:40:

A few things - Since you were on single firmware before things have changed slightly. The PicoGUS now has all the firmwares roll […]
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swisstoni wrote on 2025-06-25, 09:33:

Yes its an ESS 1688 IRQ is 2 DMA is 0 Port is 220 but I cant change the port in ESSCFG is there some way to disable the card in the config? I was previously on an old firmware that didnt have soundblaster support. The games ive bern trying to run are Doom and Duke 3D.

A few things - Since you were on single firmware before things have changed slightly. The PicoGUS now has all the firmwares rolled into one package and the default mode is soundblaster+cdrom but you can change this any time using "PGUSINIT /mode something".

E.G. if you were using the MPU401 firmware before, you would use "PGUSINIT /mode mpu". If you want to have the card start in that mode automatically each start/reset, use pgusinit /save to save the current mode to flash and it will default to whatever mode is currently set when you save.

A full list of modes is available here:
https://github.com/polpo/picogus/wiki/Configu … ng-your-PicoGUS

The ES1688 is not a PnP (that I know of) card so it's either set through the BIOS settings if it's integrated onto the motherboard or set via jumpers on the card if it's an ISA card. But it sounds like you just want the PicoGUS to stop responding as a soundblaster on port 220 which you can do by swapping modes as mentioned to disable soundblaster emulation.

polpo wrote on 2025-06-23, 02:39:

Delphius wrote on 2025-06-22, 19:28:

I am curious if there is a guide or script provided for compiling and building a proper uf2 file for picogus? I think I have the main uf2 compiling properly, but it does not seem to be the entire package. Seems I am missing something with the multi firmware support or something. I would like to try my hand at contributing, but feeling a bit stuck just getting a stock firmware compiled.

If you have a build completing you're basically already there. Sorry there's no guide, but once you know what to set it's pretty straightforward. The type of build is controlled by the PROJECT_TYPE CMake variable. To build just a single mode, you can set it to GUS (the default), SB, USB, MPU, PSG, ADLIB, NE2K, or for the full mega multifirmware build set it to MULTIFW . Almost always when I'm developing I use one of the standalone mode builds because the MULTIFW build takes longer to compile and a lot longer to upload to the Pico. I also have a special program target so I can do make program to build and immediately push my code to the Pico that is connected via a Pico debug probe.

If you're curious how the releases are built, it's all done with GitHub actions and controlled by .github/workflows/build.yml. You can see how it calls cmake -DPROJECT_TYPE=MULTIFW to configure a multifw build.

I have compiling working now. The next step was to upgrade my cmake to 3.29.2 which had to be done manually.

I was able to create a simple volume control function for the CD-ROM audio which has fixed the distortion I was getting on some games. I will look for some time to implement this out some more, but I am also wondering if I should break the functions out so they can be used beyond just controlling volume for the CD-ROM audio?

polpo wrote on 2025-06-23, 22:25:

Thanks for the reports!

@polpo Out of curiosity, was there any changes to the GUS emulation at all from V2.x to V3.x? Specifically any changes that might affect left/right channel synchronisation?

In build engine games (Tested DN3D, Blood and Shadow Warrior), the sound FX when centered has a "surround sound" effect. This usually happens when the phase between the left and right channels is inverted or delayed, similar to how Dolby Surround works. Sounds played individually on the left and right channels sound normal. It happens in the setup program as well.

In Terminal Velocity every 30-120 seconds it switches between sounding normal and "surround sound". Doom and Descent seem unaffected. The issue doesn't occur in SB mode (assuming because it's completely mono so no place desync like this could happen), I don't recall it happening in v2.x

You mentioned GUS was very time sensitive, I wonder if there is something happening where the left and right audio streams get play commands at slightly different times

I found that the left/right channel offset in GUS mode for build engine is present with the DOSBox GUS sound core. It's apparent in DOSBox 0.74-3 and DOSBox-X 2025.05.03. I also downgraded to PicoGUS v2.2.0 to confirm no change in GUS mode behaviour, it may even be present on a real GUS but I don't have one to test. SB mode has perfect left/right sync so It's probably going to be best to use SB16 mode for build games when that is available.

Curious if anyone else has experienced a random hard lock in Rise of the Triad (The HUNT Begins and Dark War) in GUS mode between 30sec to 5min of gameplay, it's stable in DOSBox and marked as compatible on the compatibility page so it may be specific to the ALI ApolloV chipset.

NeoG_ wrote on 2025-06-27, 11:25:

I found that the left/right channel offset in GUS mode for build engine is present with the DOSBox GUS sound core. It's apparent in DOSBox 0.74-3 and DOSBox-X 2025.05.03. I also downgraded to PicoGUS v2.2.0 to confirm no change in GUS mode behaviour, it may even be present on a real GUS but I don't have one to test. SB mode has perfect left/right sync so It's probably going to be best to use SB16 mode for build games when that is available.

Try and find a SVN build of regular DOSBox if you can, there were fixes made to GUS interpolation a few years ago that corrected samples being interpolated incorrectly between channels. Supposedly the fork where the code for PicoGUS was taken from didn't have these issues but it doesn't sound like that is true...
The changes for reference: https://sourceforge.net/p/dosbox/code-0/4387/

jmarsh wrote on 2025-06-27, 13:31:

Try and find a SVN build of regular DOSBox if you can, there were fixes made to GUS interpolation a few years ago that corrected samples being interpolated incorrectly between channels. Supposedly the fork where the code for PicoGUS was taken from didn't have these issues but it doesn't sound like that is true...
The changes for reference: https://sourceforge.net/p/dosbox/code-0/4387/

I tried two more DOSBox releases, SVN r4483 and Staging and the behaviour is consistent, with the exception of 0.74-3 where GUS stereo is rendered in mono (I believe that is the channel separation issue that was fixed?), but you can still hear the left/right offset in mono as a fast echo

I made two audio captures from SVN r4483 to see exactly what is happening, the left channel is delayed with GUS but spot on with SB16. It's very consistent which makes me wonder if it's a real GUS artifact from a hack job in the game's sound drivers.

NeoG_ wrote on 2025-06-28, 00:50:

I tried two more DOSBox releases, SVN r4483 and Staging and the behaviour is consistent, with the exception of 0.74-3 where GUS stereo is rendered in mono (I believe that is the channel separation issue that was fixed?), but you can still hear the left/right offset in mono as a fast echo

I made two audio captures from SVN r4483 to see exactly what is happening, the left channel is delayed with GUS but spot on with SB16. It's very consistent which makes me wonder if it's a real GUS artifact from a hack job in the game's sound drivers.

This issue happens on a real GUS in Build engine games. The right channel is just a bit earlier than the left. Attached are screenshots of the start of the Sound FX card test in Duke3D's setup on both a PicoGUS (which has lower amplitude due to the passive mixing in my analog section) and real GUS.

When you first posted about the issue I couldn't think of a way how left/right channels would be out of sync with how the GUS emulation is coded but I wanted to verify against a real GUS just to make sure before replying.

Found time to test out new CDROM feature. Worked flawlessly. I had only minor issue when PicoGUS suddenly switched CD when playing Hexen. I used cheat codes to advance levels and it started to play previous CD audio track in my 3 CDs list. It was fluke because I could not reproduce it afterwards after using it 3-4h stright.
CDROM emulation is nice addon to my Win98/DOS VIA Apollo Pro Tualatin system. MB has build in SBPro 2.0 capability so I can dedicate PicoGUS for sountrack FM/Wavetable/Red Book audio if needed.
PicoGUS doesn't have internal line out header. Would be nice to feed it into cd-in for 2nd sound card for cleaner setups. Maybe I will hard mod my v1.1 card at some point.
Thank you polpo for your effort. Sent you little token of appreciation over Paypal for CDROM feature implementation.

Tested also Descent II. It's speedy enough to play back SVGA prerendered movie scenes.
Sidenote: With eastern Europe background we in 90ies experienced usually "streamlined" 😉 versions of games. So it was first time for me to pay attention to Descent 2 Red Book audio. Oh boy, what a transformative experience!

polpo wrote on 2025-06-28, 01:15:

This issue happens on a real GUS in Build engine games. The right channel is just a bit earlier than the left. Attached are screenshots of the start of the Sound FX card test in Duke3D's setup on both a PicoGUS (which has lower amplitude due to the passive mixing in my analog section) and real GUS.

When you first posted about the issue I couldn't think of a way how left/right channels would be out of sync with how the GUS emulation is coded but I wanted to verify against a real GUS just to make sure before replying.

Thanks for confirming Ian, I guess it goes to show there is no such thing as a perfect experience with old hardware. I also couldn't find the build engine GUS offset cataloged anywhere so I thought I might have been going crazy, you'd think after nearly 30 years someone would have mentioned it.

Now for level 2 of "the offset experience"

Terminal Velocity (V1.2 retail CD) in GUS mode randomly switches between aligned and offset. In this case I couldn't replicate it in DOSBox and it remained aligned the whole time. I confirmed the offset with an audio capture.

Audio capture (WAV): https://drive.google.com/file/d/1FwLKi2LAYV-j … iew?usp=sharing

Phase shift log
00:07 - Music start (Normal)
00:08 - Phase shift/Crackle (Offset)
00:09 - Phase shift (Normal)
00:24 - Level start (Offset)
00:41 - Phase shift/Crackle (Normal)
00:51 - Phase shift (Offset)
01:05 - Phase shift (Normal)
01:21 - Phase shift (Offset)
01:36 - Phase shift (Normal)
01:48 - Phase shift (Offset)
01:56 - Phase shift (Normal)
02:03 - Phase shift (Offset)
02:30 - Phase shift (Normal)
02:33 - Phase shift (Offset)
02:44 - Phase shift (Normal)
02:49 - Phase shift (Offset)

Can anyone test following user scenario - Keep CD image mounted and shut down or restart Windows 98SE.
I my case PC hangs at Win98 logo with "Windows is shutting down" message and never turns off/restarts.

Hey guys - I'm super excited to see the CD-ROM emulation support (especially the audio!)

vutt wrote on 2025-06-28, 08:13:

PicoGUS doesn't have internal line out header. Would be nice to feed it into cd-in for 2nd sound card for cleaner setups. Maybe I will hard mod my v1.1 card at some point.

Is it possible to mod the v2.0 card for line-out to connect a 2nd sound card? I also have a v1.x card but it lacks USB mouse support...

sofakng wrote on 2025-07-02, 00:29:

Hey guys - I'm super excited to see the CD-ROM emulation support (especially the audio!)

vutt wrote on 2025-06-28, 08:13:

PicoGUS doesn't have internal line out header. Would be nice to feed it into cd-in for 2nd sound card for cleaner setups. Maybe I will hard mod my v1.1 card at some point.

Is it possible to mod the v2.0 card for line-out to connect a 2nd sound card? I also have a v1.x card but it lacks USB mouse support...

I could be missing something, but I think you're limited to soldering to the back of the audio out jack. You could just chop one end off a CD audio cable and solder the wires directly.

This would be saving having a short 6 inch audio cable externally between the two cards line out to line in. I'm more of a fan of using a small mixer so you can control volumes when games are running.

Thanks but isn't that amplified output instead of line-out? I'm not too knowledgeable about audio but I thought there was a different between line-out and speaker (amplifier?) out. I think we need line-out to feed into another sound card (or most mixers?)

sofakng wrote on 2025-07-02, 22:37:

Thanks but isn't that amplified output instead of line-out? I'm not too knowledgeable about audio but I thought there was a different between line-out and speaker (amplifier?) out. I think we need line-out to feed into another sound card (or most mixers?)

It's line out, you want to feed it into powered speakers rather than connected headphones directly into it. I have it going directly to the line-in of a Sound Blaster.

sofakng wrote on 2025-07-02, 22:37:

Thanks but isn't that amplified output instead of line-out? I'm not too knowledgeable about audio but I thought there was a different between line-out and speaker (amplifier?) out. I think we need line-out to feed into another sound card (or most mixers?)

The audio jack on the PicoGUS is a line level output so there's no issues running it into other sound cards or line inputs. But the output is lower compared to sound cards of the time so it can be difficult to get it level matched.

I have a general question on a somewhat nuanced subject. I am looking at the ESS1869 XTREME card with the AMD Interwave chip from the guys who did the Orpheus. Do I want the Interwave? Or is a pico Gus really what I want? It seems like the Interwave is just a giant headache; seemingly needing to patch everything. Ultimately I really only want it for GUS specific stuff.

Any light anyone could shed in aiding my decision would be welcome. Also. The one with the Interwave is a $140 USD more. Like you can almost buy 3 picoGus’s for the price.

Bjlled wrote on 2025-07-06, 01:46:

I have a general question on a somewhat nuanced subject. I am looking at the ESS1869 XTREME card with the AMD Interwave chip from the guys who did the Orpheus. Do I want the Interwave? Or is a pico Gus really what I want? It seems like the Interwave is just a giant headache; seemingly needing to patch everything. Ultimately I really only want it for GUS specific stuff.

Any light anyone could shed in aiding my decision would be welcome. Also. The one with the Interwave is a $140 USD more. Like you can almost buy 3 picoGus’s for the price.

I think PicoGUS at the moment mimics the original GF1 by default. It can be made to behave like Interwave by setting "/gus44k 1" though it does have side effects (see pgusinit manual).

The downside at the moment is that PicoGUS' SB mode is only 2.0, though from my testing it's already performing better in some cases compared to a real Creative SB16. I think SBPro support is currently in the works, and if that becomes formal it should have similar features compared to the card you mentioned, though only one mode (SB or GUS) at a time.

LSS10999 wrote on 2025-07-06, 02:23:

The downside at the moment is that PicoGUS' SB mode is only 2.0, though from my testing it's already performing better in some cases compared to a real Creative SB16. I think SBPro support is currently in the works, and if that becomes formal it should have similar features compared to the card you mentioned, though only one mode (SB or GUS) at a time.

I am getting the ESS card. I can get it with or without Interwave GUS PnP. But if GUS PnP is a big hassle; maybe I don’t want it, and would rather have a PicoGus for the regular gravis support. Just trying to figure that out. Something/ anything actually preferred about the Interwave vs the original ?