Hi,

These instructions explain how to install DOS 6.22 from floppy disks into 
a hard disk image using plex86.  I thought I would post this in case it
might be useful to someone else.


1) Compile plex86 according to the README distributed with the source
code.

2) Create a hard disk image. This information comes from the bochs
documentation.

   Size  Cyl  Heads Sectors/Track Sectors
   --------------------------------------
   10MB  306  4     17            20808
   20MB  615  4     17            41820
   30MB  615  6     17            62730
   46MB  940  6     17            95880
   62MB  940  8     17            127840
   112MB 900  15    17            229500
   126MB 256  16    63            258048
   483MB 1024 15    63            967680
   504MB 1024 16    63            1032192

Use the dd command to create the image:

   dd if=/dev/zero of=mydisk bs=512 count=Sectors

where mydisk is the filename to contain the image, and Sectors is the
sectors from the table above.  So to create a 483MB disk image you would
execute:

   dd if=/dev/zero of=486M.DOS bs=512 count=967680


3) Create a plex86 configuration file.  Here is an example file that works
for installing DOS 6.22 from floppys:

####################################################################
# This is an example plex86 configuration file
####################################################################


####################################################################
# Memory settings
####################################################################

# number of megabytes for vm
memory = 16


####################################################################
# Plugins
####################################################################

plugin = ./plugins/bochs/plugin-bochs.so
bochs-opt boot: a
bochs-opt floppya: 1_44="/dev/fd0", status=inserted
bochs-opt diskc: file="../483M.W98", cyl=940, heads=8, spt=17
bochs-opt cdromd: dev=/"dev/cdrom", status=inserted
bochs-opt keyboard_serial_delay: 200
bochs-opt floppy_command_delay: 500
bochs-opt vga_update_interval: 300000
bochs-opt mouse: enabled=0
bochs-opt private_colormap: enabled=0
bochs-opt i440fxsupport: enabled=1
bochs-opt newharddrivesupport: enabled=1
bochs-opt ips: 1000000
bochs-opt time0: 938581955
bochs-init


# Replay IO events from a previous run.  For now this let's us
# program the VGA adapter, without booting via the BIOS.
plugin = ./plugins/misc/replay_io.so file=../misc/vga_io.log

# The system BIOS
load-rom file=../bios/BIOS-plex86-2000_0817a address=0xf0000

# The VGA BIOS
load-rom file=../bios/VGABIOS-elpin-2.40 address=0xc0000

####################################################################
# Debugging settings
####################################################################

# syntax for disassembly
db_syntax = at&t


####################################################################
# VM tweaks            
####################################################################
  
# Maximum depth that the scan-before-execute code will try
# to recursively prescan code in the current code page, by
# following intra-page branches.
prescan_depth = 3
#prescan_depth = 1


####################################################################
# end of config file
####################################################################

4) Next, make sure that you have read/write access to your floppy
device.  You can do this either by running plex86 as root, or setting up
proper permissions on the device.  I just ran plex86 as root.  You do not
have to mount the floppy disk.

5) Make sure the floppy disk is not write protected.  I found that if the
boot disk is not writeable, plex86 won't boot the disk for some reason.

6) Load the kernel module by running the misc/load_module.sh script.

7) Put the DOS 6.22 boot disk in the floppy drive and type the following:

cd user
./plex86 -f ../conf/myconfig

where myconfig is the name of your configuration file.

8) Sit back and relax.  This will take a while.  On my Celeron 466, it
took 1-2 hours to install.

Next I'll try to install Windows 98.

Mike


Reply via email to