Running Commander Keen 4 CGA from 360k floppy disks
Commander keen 4, 5, and 6 will run (crawl) on as little as a 4.77mhz 8088 with 640k, but the software assumes you have at least a 720k floppy drive.
Well, it is possible to run Keen 4 CGA from two 5.25" 360k floppy disks, and the first one can be bootable. It requires a dual floppy drive system, but no hard drive is required.
The easy way:
Make a bootable DOS 3.3 system disk using SYS or FORMAT. Make sure to add command.com and append.com to this disk. Those should be the only two DOS files besides the hidden system files on the disk.
Create an autoexec.bat file that includes the line
"APPEND B:\"
Optionally, add the keen executable to the next line in the autoexec.bat, for example:
"KEEN4C -nowait"
copy all the following keen files to this disk:
audio.ck4
config.ck4
gamemaps.ck4
keen4c.exe
Copy the following file to a second floppy disk:
Cgagraph.ck4
That's it, just keep the first floppy in drive A:, the second floppy in drive B: and boot the computer. When keen4c on drive A: looks for the cgagraph file, DOS will force it to look in the B: drive.
The hard way, that may be desirable for different DOS version that to not have APPEND.
Make a bootable DOS system disk using SYS or FORMAT. Make sure to add command.com if not already present. You should not need any additional DOS files.
Optionally, add the keen executable to the autoexec.bat, for example:
"KEEN4C -nowait"
use UNLZEXE to uncompact the KEEN4C.EXE file
use a hex editor to change the reference to "CGAGRAPH.CK4" to "B:\CGAGR.CK4"
copy all the following keen files to this disk:
audio.ck4
config.ck4
gamemaps.ck4
keen4c.exe - this is your modified copy
Copy the following file to a second floppy disk:
cgagraph.ck4
rename this copy of "CGAGRAPH.CK4" to "B:\CGAGR.CK4"
Now, just keep the first floppy in drive A:, the second floppy in drive B: and boot the computer. When keen4c on drive A: looks for the cgagraph file, it will look for the file on drive B: instead.
This copy will always look for the file in drive B:, so do not try to use this modified executable on a hard drive.
It looks like the same should work for Keen 6 CGA.
Keen 5 CGA won't quite fit. The CGA graphics file is a bit too large. However it may be possible to squeeze it in using a 10-sector floppy disk format, that formats a 360k disk with a capacity of 400k to 420k.
The EGA/VGA versions are much larger, and won't fit. I don't think disk compression would help, as compression drivers might not leave enough free RAM to run keen.
Well, it is possible to run Keen 4 CGA from two 5.25" 360k floppy disks, and the first one can be bootable. It requires a dual floppy drive system, but no hard drive is required.
The easy way:
Make a bootable DOS 3.3 system disk using SYS or FORMAT. Make sure to add command.com and append.com to this disk. Those should be the only two DOS files besides the hidden system files on the disk.
Create an autoexec.bat file that includes the line
"APPEND B:\"
Optionally, add the keen executable to the next line in the autoexec.bat, for example:
"KEEN4C -nowait"
copy all the following keen files to this disk:
audio.ck4
config.ck4
gamemaps.ck4
keen4c.exe
Copy the following file to a second floppy disk:
Cgagraph.ck4
That's it, just keep the first floppy in drive A:, the second floppy in drive B: and boot the computer. When keen4c on drive A: looks for the cgagraph file, DOS will force it to look in the B: drive.
The hard way, that may be desirable for different DOS version that to not have APPEND.
Make a bootable DOS system disk using SYS or FORMAT. Make sure to add command.com if not already present. You should not need any additional DOS files.
Optionally, add the keen executable to the autoexec.bat, for example:
"KEEN4C -nowait"
use UNLZEXE to uncompact the KEEN4C.EXE file
use a hex editor to change the reference to "CGAGRAPH.CK4" to "B:\CGAGR.CK4"
copy all the following keen files to this disk:
audio.ck4
config.ck4
gamemaps.ck4
keen4c.exe - this is your modified copy
Copy the following file to a second floppy disk:
cgagraph.ck4
rename this copy of "CGAGRAPH.CK4" to "B:\CGAGR.CK4"
Now, just keep the first floppy in drive A:, the second floppy in drive B: and boot the computer. When keen4c on drive A: looks for the cgagraph file, it will look for the file on drive B: instead.
This copy will always look for the file in drive B:, so do not try to use this modified executable on a hard drive.
It looks like the same should work for Keen 6 CGA.
Keen 5 CGA won't quite fit. The CGA graphics file is a bit too large. However it may be possible to squeeze it in using a 10-sector floppy disk format, that formats a 360k disk with a capacity of 400k to 420k.
The EGA/VGA versions are much larger, and won't fit. I don't think disk compression would help, as compression drivers might not leave enough free RAM to run keen.