GOSiERRA is a patch that will fix AUDBLAST.DRV and SNDBLAST.DRV drivers of Sierra DOS Realmode games so they will work with faster computers (like Pentium II class and higher). Released on 30.12.2002 Written and © by Martin Kiewitz

ZIP GOSiERRA 3 (ZIP File) [38.3 KB]

This software is 'e-mail ware'. This means, if you use it, please send me an e-mail or a greeting card. I just want to see, how much people are using it.


(search for Sierra, under a Dec.16 entry). From the Readme file:

First, there were great games by a company called Sierra. They were running stable and well. Then, there were new computers. Their CPUs ran faster. The problem was, that Sierra was able to develop great games, but unable to CODE GOOD SOUND DRIVERS for them.

I bought several Sierra games some time ago. Sometime in 2000, I wanted to play them again. Well, what did I see ? A nice exception. I booted DOS and slowed down my computer by disabling CPU cache. Now they worked again, but the actual gameplay was way-too-slow. Some time passed and I debugged the actual games and their driver-code. The funny thing was, that the only BIG bug was in the Init routine. Everything else went smooth without modification.

This 'Init' routine contains some code as:
- Send commands to soundcard
- wait for response

The bug was, that they delayed the 'wait for response' part in a really idiotic manner. This part is dependent on the speed of the machine, so if it executes the commands too fast, the routine will think that there was no response.

First, I patched the bug with my own code in ONE driver. Well, using this driver on some games didn't work, (great design ;-p) I wrote the patch generic, so it applied itself to any occurrence of code that is similar to the one I found.

Now another funny part: I found several different sound drivers, where the code I patched was exchanged with different code. Guess what.


Thanx to Sierra by the way ;-)

Sierra released replacement drivers, which were 'bugfixed' in the same great... I would call it Microsoft... manner.

Well, I put all those patches together into one magic program. I called it GOSiERRA and released it to the Internet...

[...1 Year passed...]

This is GOSiERRA v2. It implements the ability to patch Dynamix-games as well. So the whole Sierra game palette can be patched now. (Real-Mode only)

[...another year passed...]

This is GOSiERRA v3. It fixes my "guessing" about how the Dynamix driver format works into the real thing. It also supports a new "type" of driver that is used in some *very rare* Sierra CD versions like Willy Beamish CD (thx to Andrey Molchanov).


I got plenty of mails. Really often 'Betrayal At Krondor' was the cause.

I tried to debug that one before. I thought Dynamix games would not use the same Sierra drivers, because they didn't have them in the normal form of AUDBLAST.DRV or SNDBLAST.DRV. Well, I was wrong. I coolant debug 'Betrayal At Krondor' because the game needs too much memory. 2 days before, I found another game, that uses the same Dynamix-styled way. It is my all-time-favorite 'The Incredible Machine'. Now I noticed several funny things. First of all, every Dynamix game has THE SAME BUGGY drivers, but they put them all together in their RESOURCE-files. The real crazy part begins, when one wants to extract them. Dynamix thought it would be clever to COMPRESS them. <lol>

Now, after some hours of really pain-in-the-ass work, I got my own unpack-algo to work. Dynamix code is typical C code. And they did some workarounds for bugs in their code. It's really sad. My unpack-algo is about 400 bytes (!), theirs is about 10 times the size and REALLY slow and damn-hard to debug.



Well. I got the thing working 2 days ago. Then I had the problem, that the mouse didn't work anymore, when using SoundBlaster. On Internal Speaker sound, everything went smooth. So I thought, it would have to do with my patch. Till now. :) I really love Dynamix.

The glitch was in the IRQ probing. It gets some interrupts and restores them afterwards. Well... it tries to restore them correctly.

Some idiot just put in some command too late, so the IRQs are disabled on the wrong IRQ-Enable-Port. Which means, they will often disable HDD-controller... and well... keyboard and PS/2 port as well :)

The really crazy thing about it, is that the whole thing is working PERFECTLY under WinDOS. Why ? Because WinDOS. doesn't really have an accurate VDM and ignores IRQ-settings. OS/2 reacts on mouse-IRQ, but does ignore keyboard-IRQ (well, guess why).

This gets wired, if you see the performance. Under bare DOS *nothing* works anymore (no keyboard, no mouse), under OS/2 just mouse isn't working and under WinDOS. everything works. :-)

Now I fixed that ugly bug as well and added the patch information to GOSiERRA. It will automatically remove this bug, if it is found within any driver to be patched.


First, you have to check, if it's a Dynamix game. Just look for AUDBLAST.DRV or SNDBLAST.DRV. If any of those files is existent and is bigger than 100 bytes, it's a normal Sierra game.

In either way, copy gosierra.exe into the game directory.

Execute it using 'gosierra dynamix' in command line prompt.

Execute it using 'gosierra' or 'gosierra [driver-name]'.

After successful patching (you should get a corresponding message), you may delete gosierra.exe, because it's not needed anymore.


There are several ways to contact me. Just try 'kiewitz@netlabs.org'.

My official homepage is at: http://www.ecomstation.ru/kiewitzsoft/

I'm dedicating GOSiERRA to my father.


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