Revisiting Windows NT 4.0 MIPS on QEMU

(This is a guest post by Antoni Sawicki aka Tenox)

This was previously well covered by Gunkies and Neozeed, however as almost a decade passed, some improvements could be made and annoyances fixed.

Firstly NT MIPS now works in 1280×1024 resolution under QEMU. It previously had issues with mouse tracking, but this is now fixed. So the new image has a higher resolution.

Secondly the old images were made with FAT filesystem which I didn’t like too much. The reason for that is the infamous RISC NT osloader needs to be placed on a FAT partition. Then, if NT is installed on a second NTFS partition the default drive will be D:\, C:\ being the just the osloader drive. This was super annoying in practice. So a common procedure was to just have one FAT partition for both osloader and winnt. I have fixed it by supplying a pre-partitioned disk and specified the second partition for osloader and the first for NT.

Also I only had just a bare/vanilla image with no additional software installed. The new image includes most of the available apps, including IE3, some editors, Reskit and Visual Studio.

Lastly I wanted to figure out all the right settings and flags for qemu as they were discrepancies between different sources and nothing seem to work smoothly. The correct flags seem to be:

qemu-system-mips64el -hda nt4.qcow2 -M magnum -global ds1225y.filename=nvram -L . -rtc "base=1995-07-08T11:12:13,clock=vm" -nic user,model=dp83932

The -rtc flag is not really needed if you are ok with having the current date in the guest.

Thanks to Neozeed for figuring out the network settings! Unfortunately the old/legacy -net nic -net user is no longer working while the new -device doesn’t like dp83932. The documentation was quite helpful.

Thanks to reader Mark for pointing out the correct NVRAM settings! See comments below.

The new image with all the apps preinstalled is here and a plain “vanilla” here.

Curiously this now works right out of the box on QEMU 6.1 and is pretty smooth and stable compared to what it was before. Good job QEMU team and thank you! Just in case I still keep the old binaries for Windows made by Neozeed here.

Update: I built Yori for NT MIPS! You can download here!