DOS ain't dead

I am interested in seeing ST-DOS ran on a Book8088. I don't have one of those machines myself, so I cannot investigate how it works, but I want to make a bootable USB storage image for it.

Because it does not have other storage I/O than the USB port for USB storage sticks, and it is an XT-class machine so its BIOS probably does not support LBA, I need to know how it detects the geometry of the USB stick. Usually all USB images of modern operating systems only use LBA, because they assume that the BIOS supports it. That's also what the current USB storage image of ST-DOS does.

The FAT filesystem is very dependent on the geometry of the disk, so the problem is that the same filesystem image does not fit all USB storage sticks.

Does the BIOS call int13,8 work normally for the USB drive? In that case it should be possible to write a bootloader that adjusts itself to the geometry that is returned by the BIOS.

> I am interested in seeing ST-DOS ran on a Book8088. I don't have one of
> those machines myself, so I cannot investigate how it works, but I want to
> make a bootable USB storage image for it.
>

Question:
Without one of those machines in your possession...
how do you plan to try any suggestion that anyone might provide ? ;)

---
--
http://glennmcc.org/

Maybe e.g. BOCHS could set user CHS geometry?

---
DOS gives me freedom to unlimited HW access.

> I am interested in seeing ST-DOS ran on a Book8088. I don't have one of
> those machines myself, so I cannot investigate how it works, but I want to
> make a bootable USB storage image for it.
>
> Because it does not have other storage I/O than the USB port for USB
> storage sticks, and it is an XT-class machine so its BIOS probably does not
> support LBA, I need to know how it detects the geometry of the USB stick.
> Usually all USB images of modern operating systems only use LBA, because
> they assume that the BIOS supports it. That's also what the current USB
> storage image of ST-DOS does.
>
> The FAT filesystem is very dependent on the geometry of the disk, so the
> problem is that the same filesystem image does not fit all USB storage
> sticks.
>
> Does the BIOS call int13,8 work normally for the USB drive? In that case it
> should be possible to write a bootloader that adjusts itself to the
> geometry that is returned by the BIOS.

Book8088 boots off a CompactFlash slot with XT-IDE BIOS add-on. You can see comparisons between my Dell 316SX (i386) and the Book8088 here - https://www.bttr-software.de/forum/forum_entry.php...p;page=0&category=all&order=last_answer

I included output from BIOSDRVS.COM that comes with XT-IDE. https://www.xtideuniversalbios.org/binaries/r625/biosdrvs.com

> Book8088 boots off a CompactFlash slot with XT-IDE BIOS add-on. You can
> see comparisons between my Dell 316SX (i386) and the Book8088 here -
> https://www.bttr-software.de/forum/forum_entry.php...p;page=0&category=all&order=last_answer
>
> I included output from BIOSDRVS.COM that comes with XT-IDE.
> https://www.xtideuniversalbios.org/binaries/r625/biosdrvs.com

According to that it seems that Book8088 already supports LBA, so the USB stick image should just work.

> > I included output from BIOSDRVS.COM that comes with XT-IDE.
> > https://www.xtideuniversalbios.org/binaries/r625/biosdrvs.com
>
> According to that it seems that Book8088 already supports LBA, so the USB
> stick image should just work.

As far as I remember, there is a thread here about Book8088 crashing FreeDOS because the XT-IDE BIOS was compiled *without* LBA support and there was a bug in how the main BIOS then reported not having LBA support, which overwrote some important other data in RAM. I hope this got fixed in BIOS updates, but I doubt that they compile XT-IDE with LBA support now?

---
FreeDOS / DOSEMU2 / ...

> > > I included output from BIOSDRVS.COM that comes with XT-IDE.
> > > https://www.xtideuniversalbios.org/binaries/r625/biosdrvs.com
> >
> > According to that it seems that Book8088 already supports LBA, so the
> USB
> > stick image should just work.
>
> As far as I remember, there is a thread here about Book8088 crashing
> FreeDOS because the XT-IDE BIOS was compiled *without* LBA support and
> there was a bug in how the main BIOS then reported not having LBA support,
> which overwrote some important other data in RAM. I hope this got fixed in
> BIOS updates, but I doubt that they compile XT-IDE with LBA support now?

AFAIK, Book8088 still uses a customized https://github.com/skiselev/8088_bios BIOS build which does not support USB boot. I was unable to make it work in a few feeble, naive attempts. I may give it a more concerted try if I have some time later. Not a big concern when I can create working CF cards on another machine. IIRC, the Book8088's CF loads CH375S.SYS from DOS and attempts to mount a USB drive if a compatibly formatted drive is present.

I haven't attempted to update the BIOS either. I think I need to buy another 27C EEPROM chip for such attempts.

> > > I included output from BIOSDRVS.COM that comes with XT-IDE.
> > > https://www.xtideuniversalbios.org/binaries/r625/biosdrvs.com
> >
> > According to that it seems that Book8088 already supports LBA, so the
> USB
> > stick image should just work.
>
> As far as I remember, there is a thread here about Book8088 crashing
> FreeDOS because the XT-IDE BIOS was compiled *without* LBA support and
> there was a bug in how the main BIOS then reported not having LBA support,
> which overwrote some important other data in RAM. I hope this got fixed in
> BIOS updates, but I doubt that they compile XT-IDE with LBA support now?

you may need to buy a flash chip and flash new one from https://github.com/skiselev/8088_bios

>
> you may need to buy a flash chip and flash new one from
> https://github.com/skiselev/8088_bios

That might get Oso2k going.

But the first thing that samwdpckr will need to buy is a Book8088 machine. ;)

---
--
http://glennmcc.org/

> > > > I included output from BIOSDRVS.COM that comes with XT-IDE.
> > > > https://www.xtideuniversalbios.org/binaries/r625/biosdrvs.com
> > >
> > > According to that it seems that Book8088 already supports LBA, so the
> > USB
> > > stick image should just work.
> >
> > As far as I remember, there is a thread here about Book8088 crashing
> > FreeDOS because the XT-IDE BIOS was compiled *without* LBA support and
> > there was a bug in how the main BIOS then reported not having LBA
> support,
> > which overwrote some important other data in RAM. I hope this got fixed
> in
> > BIOS updates, but I doubt that they compile XT-IDE with LBA support now?
>
> AFAIK, Book8088 still uses a customized
> https://github.com/skiselev/8088_bios

yeah, forked from version 0.9.4 which has LBA bug, even book8088 v2 has a newer BIOS but it is still 0.9.4.

> > > > I included output from BIOSDRVS.COM that comes with XT-IDE.
> > > > https://www.xtideuniversalbios.org/binaries/r625/biosdrvs.com
> > >
> > > According to that it seems that Book8088 already supports LBA, so the
> > USB
> > > stick image should just work.
> >
> > As far as I remember, there is a thread here about Book8088 crashing
> > FreeDOS because the XT-IDE BIOS was compiled *without* LBA support and
> > there was a bug in how the main BIOS then reported not having LBA
> support,
> > which overwrote some important other data in RAM. I hope this got fixed
> in
> > BIOS updates, but I doubt that they compile XT-IDE with LBA support now?
>
> you may need to buy a flash chip and flash new one from
> https://github.com/skiselev/8088_bios

and there is another fork which may perform better than above:
https://github.com/jinshin/8088_bios