This is a patch from Volker Ruppert <Volker.Ruppert@t-online.de>, who
comments: "The fdisk command reports an unusable second harddisk if the cdrom
is enabled. This patch helps, but I don't know if it is the right way."
> I have inspected the header of output file and several sample MIDI files. I
> have found two different bytes in the header. After I have changed this
> bytes Winamp could play the output file, but it showed a track time of
> 0:00. The Windows Media Player still doesn't like the file.
posted to bochs-developers on Wed, 29 Aug 2001 00:08:45 +0100
David Haslam wrote:
> I have been looking at the keyboard problem with Minix, which for
> those that haven't tried Minix results in every key press giving the
> response: ^@
>
> I am aware of the comments in the changelog that suggest removing 2
> keyboard ACKs in iodev/keyboard.cc, but this is a bit of a hack,
> (which is presumably why it was never incorporated).
>
> The problem seems to be that the Minix keyboard driver doesn't obey
> the rules, and Bochs doesn't model the 8042 accurately. When issuing
> commands to set the LEDs, Minix polls the 8042 output data register
> waiting for an ACK even though the OBF flag isn't set.
>
> Bochs returns zero under these circumstances, which seems to
> trigger obscure behaviour that messes up the Minix internal
> keyboard queue. I don't fully understand why Minix breaks, but I
> think the fact that the ACK generates an interrupt, and Minix treats
> it as a scan code also has something to do with it.
>
> In any case, I believe, the fix is for Bochs to return the output
> buffer contents, regardless of whether the OBF flag (called outb in
> Bochs) is set.
>
> I expect the real hardware allows the register to be read at anytime,
> and with this fix we are modelling the behaviour of the hardware more
> accurately.
>
> I have tested it with Minix 2.0.0. Also DOS 6.22 still works after this fix.
> Does anyone think this will break anything else?
>
> This diff is against the latest CVS of iodev/keyboard.cc, version 1.29
> The last part of the diff is a minor fix to an unrelated debug print.
Fixed a "feature" in pc_system.cc with setting timers to small values
that can cause bochs to hang.
Significantly improved the performance of the new PIT.
It's probably ready to become the default now.
Added a preliminary implementation of the slowdown timer
that Bryce and I had talked about.
Also added a hack to keep the OpenBSD timer problem from filling the log.
The new PIT seems to work, but until some
enhancements are made to the way the timers
and devices.cc work, it'll be slower than
the old one.
