Prez wrote on 2025-11-17, 19:59:

So i'm not wrong, maybe you just have to MOVE the actual resistor below its actual place and it would be okay ?

Since it's a pull-down resistor it might have a pretty high value like 4.7k ohms, because a pull-down at low resistance is really not common and is very likely bad practise.

I'm going to try out this modification soon too, I like my Tecra 8200 especially since it can do pixel perfect integer scaling of VGA res, but it's not very compatible with DOS games so far.

Thank you very much for sharing this with well detailed pictures and info theeuwke 😀

theeuwke wrote on 2025-11-11, 09:52:

I'm also an owner of the Tecra 8200 Laptop, with the same issue - not beeing able to remap IRQ 11, and stuck with INT#. […]
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I'm also an owner of the Tecra 8200 Laptop, with the same issue - not beeing able to remap IRQ 11, and stuck with INT#.

So I took my chances and opened up the laptop and inspected the YMF754-B:
On the YMF754
PIN 46: SERIRQ#
PIN 47: PCGNT#
PIN 48: PCREQ#

Measuring on the ICH2 side is difficult because of the package, and you'll need to disassemble the whole laptop to get beneath it.

So the problem with the Tecra, is that only PCGNT/PCREQ are connected to the ICH2-M southbrigde (for DMA), but SERIRQ# is pulled down and disconnected from the southbridge. I took the gamble, and removed the pull down and soldered a 0 Ohm (perhaps 22 ohm was safer) to the 'connection through' pads simular to the PCREQ/PCGNT - these are also connected via 0 Ohm resistors.

So far no issues, and - IRQ5 now works with S-DMA!

I also modified Phils setupds.exe ICH2 version, because the PCI-ISA Bridge PCIID is a bit different on the ICH2-M, but I don't think it make a difference.

Hi everyone !
It works perfectly ! At the first reboot, everything is fine, i choose IRQ 7 for myself and everything is okay ! Doom, Prince Of Persia, Descent, Arkanoid 2, etc etc etc.
Amazing find, thank you so much !! I will update the thread title 😀

Best regards
Philippe Dubois

Prez wrote on 2020-06-18, 12:10:

Hi all ! […]
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Hi all !

I'm a good user of Vogons so i did some research, but didn't find answers for my problem.
I own a Toshiba Satellite Pro SP4270 wich has a Yamaha YMF744 and everything is perfect with drivers found here or at PhilsComputer Lab :
- Sounds with soundblaster pro settings in DOS
- OPL3 in DOS
- XG wavetable under W98SE and still OPL and SB Pro sounds

So its a nealry perfect labptop for MS-DOS gaming !

But i just got a Toshiba Tecra 8200 with a Yamaha YMF754, a bit more sexier machine. So, i tried at once the drivers i used on the 4270, but they don't work. No sound at all. When launching setupds /s , it tells me everything is using IRQ 5, but nothing works.

I went on trying to understand what are the 'big' differences between the SP4270 and the Tecra 8200 , I discovered they useda different chipset. The Tecra 8200 is based upon an Intel ICH2-M 81815 it seems, so i used the modified setupds.exe for Intel ICH2 and it does produce a slightly different result, i got music working under DOS (OPL) but still no SB sound at all. Setupds now tells me that it is IRQ11 which is used, and it seems i cannot change that (?).

If anyone can help me to understand, it would be great, thanks !

Best regards,
Philippe Dubois

Hi Prez

I have a Toshiba Satellite 4200 (I think its the 4260), so it has the same yamaha sound chip as yours. I want to get it working well in DOS and I note you reference the laptop is working well using drivers from PhilsComputerLab.

Do you have any installation / configuration advice? as there isn't much info on this model of laptop.

I've downloaded the dos drivers (which include DSDMA, SETUPDS, YMFIRQ, LOADTSR etc). what do I need to include in autoexec.bat / config.sys?

Thanks
Matt

MrBooble wrote on 2025-12-29, 16:19:

Do you have any installation / configuration advice? as there isn't much info on this model of laptop.

I've downloaded the dos drivers (which include DSDMA, SETUPDS, YMFIRQ, LOADTSR etc). what do I need to include in autoexec.bat / config.sys?

I have Toshiba Satellite Pro 4280XDVD, everything works Aladdin, Doom2, MK, Prince of Persia etc. my settings in autoexec.bat:

SET BLASTER=A220 I7 D1 T4
LH C:\DOS\AUDIO\YMF744\SETUPDS.EXE /S

You must use setupds.exe version 3.11

DS.INI file contain next lines:

LEGEN=1
SBIO=0
SBIRQ=1
SBDMA=1
MPUIO=1
MPUIRQ=4
JOYIO=4
INTAIRQ=11
IRQMODE=2
DMAMODE=0
FIRSTTRY=0
SLAVEBASE=0
SLAVEADDR=8000
LEGMAS=77
VOICE=77
FM=77
MASTER=0
MONO=0
PCBEEP=0
PHONE=8
MIC=d
LINE=808
CD=808
VIDEO=808
AUX=808
PCM=808
SBFILE=YMH8.WAV
NAFILE=YMH16.WAV
FMFILE=YMH.MID

Wow, cool stuff @theeuwke thanks

Looks like, i need to do some soldering 😀

MAZter wrote on 2025-12-31, 19:09:

I have Toshiba Satellite Pro 4280XDVD, everything works Aladdin, Doom2, MK, Prince of Persia etc. my settings in autoexec.bat: […]
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MrBooble wrote on 2025-12-29, 16:19:

Do you have any installation / configuration advice? as there isn't much info on this model of laptop.

I've downloaded the dos drivers (which include DSDMA, SETUPDS, YMFIRQ, LOADTSR etc). what do I need to include in autoexec.bat / config.sys?

I have Toshiba Satellite Pro 4280XDVD, everything works Aladdin, Doom2, MK, Prince of Persia etc. my settings in autoexec.bat:

SET BLASTER=A220 I7 D1 T4
LH C:\DOS\AUDIO\YMF744\SETUPDS.EXE /S

You must use setupds.exe version 3.11

DS.INI file contain next lines:

LEGEN=1
SBIO=0
SBIRQ=1
SBDMA=1
MPUIO=1
MPUIRQ=4
JOYIO=4
INTAIRQ=11
IRQMODE=2
DMAMODE=0
FIRSTTRY=0
SLAVEBASE=0
SLAVEADDR=8000
LEGMAS=77
VOICE=77
FM=77
MASTER=0
MONO=0
PCBEEP=0
PHONE=8
MIC=d
LINE=808
CD=808
VIDEO=808
AUX=808
PCM=808
SBFILE=YMH8.WAV
NAFILE=YMH16.WAV
FMFILE=YMH.MID

The attachment 2025-12-31 13.57.38.jpg is no longer available

Thank you! Much appreciated

Prez wrote on 2025-12-29, 13:12:

Hi everyone ! It works perfectly ! At the first reboot, everything is fine, i choose IRQ 7 for myself and everything is okay ! D […]
Show full quote

theeuwke wrote on 2025-11-11, 09:52:

I'm also an owner of the Tecra 8200 Laptop, with the same issue - not beeing able to remap IRQ 11, and stuck with INT#. […]
Show full quote

I'm also an owner of the Tecra 8200 Laptop, with the same issue - not beeing able to remap IRQ 11, and stuck with INT#.

So I took my chances and opened up the laptop and inspected the YMF754-B:
On the YMF754
PIN 46: SERIRQ#
PIN 47: PCGNT#
PIN 48: PCREQ#

Measuring on the ICH2 side is difficult because of the package, and you'll need to disassemble the whole laptop to get beneath it.

So the problem with the Tecra, is that only PCGNT/PCREQ are connected to the ICH2-M southbrigde (for DMA), but SERIRQ# is pulled down and disconnected from the southbridge. I took the gamble, and removed the pull down and soldered a 0 Ohm (perhaps 22 ohm was safer) to the 'connection through' pads simular to the PCREQ/PCGNT - these are also connected via 0 Ohm resistors.

So far no issues, and - IRQ5 now works with S-DMA!

I also modified Phils setupds.exe ICH2 version, because the PCI-ISA Bridge PCIID is a bit different on the ICH2-M, but I don't think it make a difference.

Hi everyone !
It works perfectly ! At the first reboot, everything is fine, i choose IRQ 7 for myself and everything is okay ! Doom, Prince Of Persia, Descent, Arkanoid 2, etc etc etc.
Amazing find, thank you so much !! I will update the thread title 😀

Best regards
Philippe Dubois

I tested the pull-down resistor off of the board and it's 10k, so definitely need a low value resistor rather than just moving that existing resistor.

I think the size is 0402? I was able to find a 33 ohm 0603 resistor on a parts board and bodge that across diagonally to connect it up which seems to be working great! I said DOS audio was working in Windows 98 in previous posts but I recall there was something really not working well - now it's working far better with games like Wolf3D working without issue. Though in Windows 98, disabling the IR device freed up enough resources for the legacy audio of the DS-XG to function correctly.
Gonna have to try out DOS soon to see how compatibility is, I know there were a bunch of games I did want to play that weren't working before so pretty much stuck to Windows / DirectX gaming on this one.

There's enough room that potentially the mod could be done without removing the mainboard from the chassis - which was the big hassle of the modification, gotta pull the mainboard, pull all parts off and then pull the PCMCIA slots to get full room to work. I'm thinking I could just take off the top case and be careful with the soldering iron poking it into the limited space 😀 There's enough room between the chassis and the PCMCIA board to potentially remove the original pull-down resistor and put the new resistor on just below it.

----
edit
Okay so, this has definitely made a difference! On the one I've done the modification on, it needs to use the ICH2 setupds.exe, IRQ5 doesn't work but IRQ7 works with these settings:

With this set up, I can now get sound working in games like Sim City 2000, which previously failed with any setting I could try.

On the one I have not done the modification on with the same setup, it says it can't detect anything on IRQ5 or 7 and I can't get SB audio working in real DOS. Gonna upgrade this one soon 😁