From my notes when I tested Aureal Vortex AU8820B2 and AU8830: it uses asp4dos.com TSR that doesn't require any presence of xEMM386/V86. It load's settings from vortex.ini placed in Windows directory so it probably needs Windows to configure resources. Under DOS there's no wavetable but FM only and it sounds very shitty. It worked better under Win98 where also wavetable can be used by loading soundfont to RAM.

yes bad fm and need an ini made by windows driver. but what is fasinating about this old driver is that can work on any chipset that has pci slot without any ems! my thoughts are if this driver reversed engineered a lot can be found and made a new better sbemu.

I guess that it use some assistance of specific HW in aureal soundchip so it would't help to other soundcards... Yes it would be nice if author of the driver could put this abandonware on github to let see what magic they did...
Also ymf72x/74x dsdma.exe source would be interesting as it implements its own DPMI server but probably the same is now done with HDPMI/VDPMI...

asp4dos.com is just ~35KB, easy to disassemble. I even started, got as far as parsing parameters but couldnt quickly find any magic happening so gave up. Since its not setting any trapping it must be using DDMA.

Cacodemon345 wrote on 2026-04-26, 18:22:

Hi crazii,

Is TinySoundFont planned to be added to SBEMU? I used it in my VSBHDASF project successfully for emulation of MPU-401 output as I do not have any serial ports on any of my PCs. VSBHDA merged my TinySoundFont implementation in my fork and I haven't heard of serious issues otherwise.

(It does use floating-point math, but I presume SBEMU has the ability to handle floating-point save/restore operations correctly.)

Yes, sure. Thanks for your excellent work. I will pick a time to merge your code. It'll also be good if there's anyone who can help me to do that 😁

SBEMU doesn't use float-points in HW interrupts, but it has code to save FP states on software interrupts (driver-reset / configuration changes etc.), because the driver init routine in MPXPlay has FP operations. I think it won't be a problem.

rasz_pl wrote on 2026-04-27, 19:01:

asp4dos.com is just ~35KB, easy to disassemble. I even started, got as far as parsing parameters but couldnt quickly find any magic happening so gave up. Since its not setting any trapping it must be using DDMA.

any finding will be good. by theory about this is if we can use something they use so we can use it. and have sbemu without any ems just like aureal, with sb16 emulation and better fm and compatible with many hda chipsets

Afaik supporting DDMA should allow SBEMU to work with no IO port trapping. But it might not be worth the effort considering how limited chipset DDMA support was, looks like it ended at some early Athlon chipsets https://dosdays.co.uk/topics/pci_sound_cards_in_dos.php https://docs.google.com/spreadsheets/d/1cvhr6 … dit?gid=0#gid=0

im no programmer. i dont know how asp4dos.com is made. but is a fact that is provides sbrpo emulation on evey chipset without ems. the secret behind that compatibility is worth investigating. my humble opinion thats all

f1etch wrote on 2023-06-09, 11:47:

Having issues with Audigy card. As soon as SBEMU loads I get a contant "white noise" sound from the Audigy. Tried with Audigy (SB0090) and Audigy 2 ZS (SB0350) and get same result.

I know this is a pretty ancient post but I was having the same problem with my Audigy 2 ZS, while onboard audio worked fine (enabling it in the bios) but I wanted to run everything through the Audigy and not have to disable onboard AC97 when I wanted to use Windows etc.

I think this more of a problem with Jemmex and the motherboard I'm using, but it might help others. SBEMU and VSBHDA were both buzzing/hissing when started and no other audio would work. In config.sys I have to set:

1DEVICE=JEMMEX.EXE NOE820

No buzzing/hissing anymore.

https://youtu.be/ZAtM3plfUdA

Update:
the EMS 4.0 functions is now added, but the function 5Bh (alternate map register set), 5C (prepare EMS HW for warm boot), 5D (enable/disable OS/E Function Set) is not implemented, those mostly are used by OS (e.g. win3.x/win9x) and maybe implemented in the future along with GEMMIS. I only test 2 games, ALADDIN and LEMMING2. MSCDEX /E also tested. here's a list of programs that uses EMS https://www.vogonswiki.com/index.php/List_of_ … hat_require_EMS. I may find another time to test more.

My Thinkpad T540p only have 64K (+4K used by VDPMI) uma available, with USB support on, and LAN option ROM off. So when EMS is enabled, there is no UMB. I have to add more option to make some UMB for some drivers, e.g. DOSKEY and CTMOUSE.

Changes:

1.
/EMS option, default value=0, valid value [0-8]
/EMS equals /EMS=1, which enables EMS with default amount: 4M, /EMS=0 disables EMS, /EMS=[2-8] set amount in MB. EMS4.0 support up to 32M EMS memory but I don't think it's really needed.

2.
/MV option, default value=b000, valid value [b000-b700]. it is a specialized option for Ixxxx-B7FFF. only works when EMS enabled.
this include the monochrome video buffer. enabled by default. set /MV=0 to disable it. or /MV=b600 to include B600-B7FF. I'm considering a Ixxxx-xxxx option like EMM386, but not very sure.

3.
/EMSX option, default value=0, valid value [0-8]
this is similar to /EMS, and also set page frame to be F000, inspired by QEMM386. I don't know how QEMM does it but its idea is good. you only need either /EMS or /EMSX, not both. this option use the BIOS ROM area as page frame so that it saves the 64K for UMB. this option may have bugs, at least as I tested, it's OK for Aladdin and Lemming2.
In short, /EMSX gives you EMS without losing any of the UMB you had.

4.
Fix Lemmings2 startup freeze, not EMS related, but probably FAT32/DOS/BIOS related.

5.
Disable the "VM timing" feature, as it previously has bug and not working as expected, so it just appears OK but after I fixed that bug, the music becomes slow. disabled and may be used in debug mode.

EDIT: 6.
Fix incorrect DPMI client RM stack pointer that corrupts UMB.

Extra notes: with EMS enabled, a VDS might be needed, but as I tested for Lemmings2, without VDS it uses the page-mapped EMS address directly for DMA (while DMA controller require a physical address), I think without VDS it assumes a physical EMS board, not a emulator like EMM386 - and that works with SBEMU by chance - whether to add VDS remains undetermined.

now with /MV enabled by default, and set /EMSX, I have 96K UMB, which gives a relief.

My next plan is to integrate TSF features, after doing some clean ups. There is no exact date when I'm gonna start it yet.

Just pushed the adaption of SBEMU to VDPMI to a new branch, although the branch may have some commits behind the main branch.
the QEMM and HDPMI dependency, are removed, Virtual PIC is also removed. because VDPMI has its own virtualization. the virtual DMA will be removed in the future.

https://github.com/crazii/SBEMU/tree/vdpmi

crazii wrote on Yesterday, 11:40:

Just pushed the adaption of SBEMU to VDPMI to a new branch, although the branch may have some commits behind the main branch.
the QEMM and HDPMI dependency, are removed, Virtual PIC is also removed. because VDPMI has its own virtualization. the virtual DMA will be removed in the future.

https://github.com/crazii/SBEMU/tree/vdpmi

Thanks, crazii.

So am I right in understanding that VDPMI is intended to replace both HDPMI and any EMM solutions? So it will be used instead of Jemm or QEMM too?

Wondering this since you mention both EMS functionality as well as possibly supporting GEMMIS, as well as the fact that VDPMI would still have to support real mode games somehow, which I assume would mean that it would have to function as the V86 monitor as well, right?

But does that mean that it would not be able to coexist with any (other) EMM manager either?

crazii wrote on 2026-05-09, 16:11:

Update:
the EMS 4.0 functions is now added, but the function 5Bh (alternate map register set), 5C (prepare EMS HW for warm boot), 5D (enable/disable OS/E Function Set) is not implemented, those mostly are used by OS (e.g. win3.x/win9x) and maybe implemented in the future along with GEMMIS...

Hi, @crazii,
Does this mean, that this new fork of SBEMU in its future versions could possibly remove its dependency of HimemX memory manager? AFAK @Baron von Riedesel strongly denies the need of GEMMIS API implementation.