Working configs for HDOS on Virtual H89?

[Andrew Warkentin]

Hi everyone. I'm new to the group. I'm currently working on a virtual OS museum in the form of a Linux VM with various emulators and OS images along with a custom launcher (I'm planning to release it in the next month or so), and I'm going to include a few H8/H89 images.

I've tried various configurations (with both H17 and H37) for both the Java and C++ versions of Virtual H89, but have been completely unable to boot any version of HDOS in either. No matter what configuration I've used I haven't been able to get so much as a boot prompt out of HDOS. CP/M on the other hand seems to work fine in both though. Does anybody here have a working configuration for HDOS on either the C++ or Java version?

I have been able to get 3.02 booting in MAME, but MAME doesn't seem to emulate the H17 so I can't use it to run older pre-H37 versions. I've also got Dave Dunfield's old DOS-based emulator with its included HDOS 1.6 image running in DOSbox, but I would like to replace that with something a bit more modern if possible (if the only emulator for a particular platform is DOS-based I'll use it, but if there's something more modern I will generally use that instead).

[Joseph Travis]

If you're using original images, HDOS requires you to press the space bar a few times to auto-detect the baud rate before it completes the boot process.

Joe

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[Mark Garlanger]

Hi Andrew,

   Welcome to the group, that sounds like a great project. As Joe mentioned, if you are using images of the original distribution disks, after the initial Boot command, it will seem to hang. It is waiting for the user to press the space bar a few times, which allows HDOS to use the error flags of the 8250 serial port to match up the CPU board's baud rate with the rate used by the terminal board. 

  Are you going to allow the users to change, the disk image? The situation with hard-sectored disk image formats is a bit messy between H8D and H17 and I need cleanup how VirtualH89 is handling disk images. 

  You are correct in that MAME does not support the H17. There is some missing functionality in the core floppy disk code that makes it hard to add support for the H17. But if you are just wanting to have the software available, I can help get some of the software from h8d images on to either images for the h37, or even the MMS 8" drives. The MMS controller supports up to 4 5.25" and 4 8" drives connected at the same time. So a huge collection of software could be made available without requiring the user to change disk images.

Mark 

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[Andrew Warkentin]

On Saturday, February 14, 2026 at 4:40:25 p.m. UTC-7 Mark Garlanger wrote:

   Welcome to the group, that sounds like a great project. As Joe mentioned, if you are using images of the original distribution disks, after the initial Boot command, it will seem to hang. It is waiting for the user to press the space bar a few times, which allows HDOS to use the error flags of the 8250 serial port to match up the CPU board's baud rate with the rate used by the terminal board. 

Thanks. That gets it to boot. Not sure why the Dunfield emulator doesn't need it.

 

  Are you going to allow the users to change, the disk image? The situation with hard-sectored disk image formats is a bit messy between H8D and H17 and I need cleanup how VirtualH89 is handling disk images. 

  You are correct in that MAME does not support the H17. There is some missing functionality in the core floppy disk code that makes it hard to add support for the H17. But if you are just wanting to have the software available, I can help get some of the software from h8d images on to either images for the h37, or even the MMS 8" drives. The MMS controller supports up to 4 5.25" and 4 8" drives connected at the same time. So a huge collection of software could be made available without requiring the user to change disk images.

That would be appreciated (I would of course give you credit for creating the images; the launcher displays a field for that), although I'm probably going to use the Java implementation of Virtual H89 since that has a file selector for changing disks. It would be nice to have either hard disk or large floppy images with a bunch of applications regardless though.