Lab - DOS 6.22

For a DOS 6.22 lab environment one could have a system configuration allowing for maximum 32 MB XMS and no EMS memory in order to compensate for the inherent limited conventional memory. Nevertheless, this strategy seems useless for Microsoft ® COBOL 4.5 since it lacks the ability to take of XMS as XCOBOL in Microsoft ® COBOL 5.0.

The example below considers a Virtual PC environment:

DOS 6.22 with over 600 KB of free conventional RAM

 A sample CONFIG.SYS could be:

DOS=HIGH,UMB

FILES=100
BUFFERS=16
LASTDRIVE=Z

SHELL=C:\DOS\COMMAND.COM /E:512 /P

DEVICE=C:\VPC\VMADD386.SYS
DEVICE=C:\DOS\HIMEM.SYS /TESTMEM:OFF
DEVICE=C:\DOS\EMM386.EXE 512 RAM I=A000-B7FF

DEVICEHIGH=C:\DOS\RAMDRIVE.SYS 16384 512 /E

A sample AUTOEXEC.BAT could be:

LH C:\VPC\IDLE.COM
LH C:\VPC\FSHARE.EXE > NULL
LH C:\DOS\SMARTDRV.EXE /U /N
LH C:\DOS\DOSKEY /INSERT

PROMPT $P$G
PATH C:\DOS
SET DIRCMD=/OGNE

IF EXIST D:\NUL MD D:\TMP
IF EXIST D:\TMP\NUL SET TMP=D:\TMP

... insert the COBOL environment variables here ...

Note how I was able to get 612 KB of free conventional memory!
In particular, the 512 RAM in EMM386.EXE is essential to XCOBOL.
At this point one should be able to successfully invoke the compiler.

XCOBOL 5.0 running on DOS 6.22