This is how to not do it: GitHub Don’t get me wrong, it’s absolutely brilliant that Microsoft was able to release a fairly complete (minus DOSSHELL) source code for MS-DOS 4.00 or 4.01 (see below). As much as it was …Continue reading→

A few weeks back I was reminded that the source code to the 386MAX (later Qualitas MAX) memory manager was released in 2022 on github. Back in the 1990s I used primarily EMM386 and QEMM, but I have some experience …Continue reading→

As promised, here is the source code for the Windows 9x VirtualBox display minidriver. For discussion of the source code, see the included readdev.txt file. The code was developed on a Windows 10 host system. For extra credit, I attempted …Continue reading→

So after some furious disassembling, assembling, and linking, things got this far: It took longer than it ought to have because although IDA is great, I couldn’t figure out how to make it work with GW-BASIC’s bizarre segment usage. The …Continue reading→

When I learned that Microsoft released the GW-BASIC source code, I was mildly curious to find out what is or isn’t there. The short answer is that there’s a whole lot, but a lot is also missing. Spelling note: Both …Continue reading→

(This is a guest post by Antoni Sawicki aka Tenox) In a recent blog post I lamented the lack of a good console/cmd/PowerShell text editor for Windows. During the process I made a rather interesting discovery, that in a fact …Continue reading→

I missed this when it was initially announced. The source code for PC-MOS/386 version 5.01 is now available on github under the GPLv3 license. It requires the user to supply Borland C++ 3.1 in order to build, but there are …Continue reading→

While digging into the implementation of Sound Blaster compatibility on PCI cards, I found an unexpected gem. Ensoniq’s U.S. Patent 5,790,837 includes partial source code for the Sound Blaster emulation driver used with the Ensoniq Soundscape VIVO boards, SSINIT.COM. The VIVO boards were …Continue reading→

Note: See also an updated version. Upon reader request, the OS/2 Museum is publishing the source code to the NT video miniport driver for VirtualBox. To recap, this is a NT video miniport which allows 32-bit NT versions to use high-resolution graphics …Continue reading→