Dec 082017
Use the 64k above 640 for 704k under DOS.
File DOSMEM.ZIP from The Programmer’s Corner in
Category Utilities for DOS and Windows Machines
Use the 64k above 640 for 704k under DOS.
File Name File Size Zip Size Zip Type
CONFIG.SYS 159 109 deflated
DOSMEM.ASM 6316 1668 deflated
DOSMEM.SYS 551 507 deflated
README.DOC 8256 1882 deflated

Download File DOSMEM.ZIP Here

Contents of the README.DOC file

This device driver will make the extra 64k accessable to
Dos. Bringing the DOS top limit to 720k. I use this to activate the 64k
at boot-up. Below is what CHKDSK finds as far as memory. I have included
the source code so that any improvements you make please let me know what
and why you made what ever changes you did. This is released into the
public domain to use modify and most of all learn from. If you incounter
any problems please let me know but don't blame ME!!! The type of system
that I know for sure it works on is MINE!!!. I have a true BLUE PC-XT
with four banks of 256k memory chips and the U44 Module has been changed
to allow this modification to the main motherboard. The U44 chip is
available from ...... CY ATKINSON
5218 Running Bear Drive
San Jose, CA 95136

One other thing this is my BIOS chip in my PC-XT is dated
Nov.8,1982. The IBM part # is 1501512 for this level of BIOS. The
section below is what CHKDSK see's as far as memory is concerned. This
was done by useing the command "P:CHKDSK>CHKDSK.DOC" try this command
on what ever drive you want to it will work on a floppy to be safe.

Volume HD12 HDRVP created Jul 3, 1988 6:17p

13,045,760 Bytes Total Disk Space
0 Bytes in 1 Hidden Files
45,056 Bytes in 10 Directories
7,929,856 Bytes in 339 User Files
4,096 Bytes Per Cluster
5,070,848 Bytes Available on Disk

720,896 Bytes Total Memory
611,264 Bytes Free

If you use the utility and give it the command
"PMAP>PMAP.DOC" you can also create your own for your system. Below
is what mine looks like so you can see that use over 100k of memory
resident and still have 611,264 left for DOS applications, also I
am running under IBM DOS 3.2.

pmap 1.32 Copyright (C) 1986-1988 by The Cove Software Group/C.J.Dunford

Addr Program Parent Parameters Han Blks Size Vectors
---- ------- -------- --------------- --- ---- ------- -------
1164 command command 1 2 6256 22 23 24 2E FC
130B fastk command /S/P/4 0 2 1168 09 1C
1356 graphics command ?? 0 2 1424 05 EF
13B1 regain command REGAIN.PRO 0 2 19056 21 F4
185A cache-em command /H 0 2 10112 13 19
Total conventional free memory 2 611472
Largest conventional free block 611424
Next program will load at 1AD4

Expanded memory summary:

Block Size Name
----- ------- ----
0 0
1 1114112
2 720896
3 262144
Free 0
Total 2097152
Page frame segment: CC00h

From The No Games BBS
320 Meg Online at 300,1200,2400 & 9600
Using the U.S.Courier HST 9600 Modem
1-919-364-7378 24 Hrs Aday

I have included a example of my config.sys file the dosmem command
must be the first line in your config.sys file because it does a double
boot but don't worry this is not a trojan if the memory is not available
then DOSMEM will tell you so and continue on.
The command line is "DEVICE=DOSMEM.SYS 704".

Please if you make any changes please let me know you can reach my
board any time of day at 1 919 364-7378.

JeFfReY BaRnEs SYSOP of the NoGames
1 919 364-7378.....HST 9600

 December 8, 2017  Add comments

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