Re: Minix 1.1 with QEMU

[Will Senn]

On 9/23/20 11:53 AM, Philippe Mathieu-Daudé wrote:

> Hi Will,
>
> On 9/23/20 6:45 PM, Will Senn wrote:
> > Long time user, first time poster :)
> >
> > So, I'd like to be able to run Minix 1.1 on my Macbook Pro mid-2012
> > w/16gb RAM (MacOS 10.14.6 Mojave). Qemu will run pretty ancient OS'es
> > such as DOS 2.0, which I use all of the time. However, I'm having some
> > difficulty getting Minix to run. I am able to boot the first floppy, but
> > when I change to the second floppy, the system freezes and I can't tell
> > what is going on. Here's what I did to get this far:
> >
> > brew install qemu
> >
> > qemu-system-i386 --version
> > QEMU emulator version 5.1.0
> >
> > mkdir ~/workspaces/retro-workspace/minix-1.1
> > cd ~/workspaces/retro-workspace/minix-1.1
> > aria2c
> > http://download.minix3.org/previous-versions/bzipped/Intel-1.1.tar.bz2
> > tar xvjf Intel-1.1.tar.bz2
> > cp Intel-1.1/floppy_disk1 ./Disk01.img
> > cp Intel-1.1/floppy_disk2 ./Disk02.img
> > cp Intel-1.1/floppy_disk3 ./Disk03.img
> > cp Intel-1.1/floppy_disk4 ./Disk04.img
> >
> >
> > qemu-system-i386 -drive
> > file=Disk01.img,format=raw,if=floppy,media=disk,readonly=off,index=0,snapshot=on
> > \
> >   -boot a \
> >   -no-fd-bootchk \
> >   -monitor telnet::2222,server,nowait -serial mon:stdio
> >
> > Qemu boots to the Minix 1.1 Boot screen and says to swap to floppy 2, so
> > in the monitor:
> > change floppy0 Disk02.img raw
> >
> > I press l (el) and it scans the disk, lists the files on the disk and
> > reports no errors, but when I press =, it does a carriage return and
> > just sits there. I'm pretty sure this is the Minix going bye bye and not
> > necessarily QEMU, but I'm wondering if there is a way to see what QEMU
> > thinks it is doing or if it is what's hung? Usually, at this point,
> > Minix reads the disk contents into a Ramdisk and boots Minix.
> >
> > Food for thought... Minix expects to run on an IBM PC (5150), IBM PC XT
> > (5160), or compatible, and therefore the I/O is written for whatever
> > floppy controller was extant at that time (I'm guessing here), so if
> > that's different than modern day floppies, I suppose this could cause
> > the problem I'm experiencing here. Is there a way to see the floppy
> > controller activity in QEMU? Similarly, I gather it expects a CGA
> > compatible monitor (EGA/VGA, etc should be fine).
> >       
> Can you try adding '-machine isapc', which is closer to the 5150?
>
> > I appreciate your help on this.
> >
> > Minix 1.1 works 'ok' in 86Box and other IBM PC emulations, so I know the
> > floppies are fine.
> >
> > Thanks!
> >
> > Will
> >
> >
> >
> > -- 
> > GPG Fingerprint: 68F4 B3BD 1730 555A 4462  7D45 3EAA 5B6D A982 BAAF
> >
> >       
>     
    Phillipe,
      
      My new incantation is:
      
      qemu-system-i386 -machine isapc -drive
file=Disk01.img,format=raw,if=floppy,media=disk,readonly=off,index=0,snapshot=on  
      -boot a   -no-fd-bootchk   -monitor telnet::2222,server,nowait
      -serial mon:stdio
      
      with the same outcome :(. Thanks for the suggestion, I'll keep it
      in mind for other projects.
      
      Will
    
-- 
GPG Fingerprint: 68F4 B3BD 1730 555A 4462  7D45 3EAA 5B6D A982 BAAF