Hi,

This is v0.5 of pcm, a PC eMulator.  There are many shortcomings, but
it already boots MSDOS and DRDOS.  You really need to have X going,
though there is a half-baked tty interface for text-based programs.

To compile the pcm source, make sure the Makefile has the right paths
to the X includes/libraries and do a make.  If you don't have X up,
you might try the tty target instead (and have a look at the pcm.tty
script).  On startup, pcm reads a file called .pcmrc in the current
directory.  It contains information on mapping the bios, keyboard and
floppy disks.  Lines with '#' as their first character are ignored.

BIOS: The bios source is in pcmbios.asm.  Use the real-mode assembler
provided (rasm) to assemble it.  The bios is liberally sprinkled with
special escapes to the emulator.  My goal is to work toward reducing
these as much as possible.  Specify the bios file in .pcmrc.  E.g.,
"bios pcmbios.bin"

VIDEO: This needs more work.  Currently only things that go through
BIOS int 10 make it to the screen.  The scrolling and cursor update
occasionally leaves little artifacts around as well.  At least CLS
works.  BTW, I am an X novice so if you see something in window.c that
is stupid and you can do better, please dive right in.

KEYBOARD: The keyboard interface directly maps X keycodes into PC scan
codes.  You need to setup a key definition file that specifies this
mapping.  There are example files for apollo, dec and sun keyboards.
There is also a perl script (new.keys) which may be useful in
generating new key files.  Specify the keyboard in .pcmrc.  E.g.,
"keys sun.keys"

FLOPPY: Up to 4 floppies are supported.  Right now only 720k, 360k
1.2m and 1.44m are included. Other types are straightforward to add
(look in main.c).  Specify these in .pcmrc. E.g., "floppy boot.dsk
360k".  Floppies are assigned in the order seen in .pcmrc.  You must
assign at least the boot floppy (A:).  Since network drives are not
yet implemented, you need to use mtools to transfer files to the
floppy images.

For other miscellaneous info, see the file "notes".

Good Luck

Gary Beihl (gary.beihl@columbiasc.ncr.com)  28 April 1992