mirror of
https://github.com/SEPPDROID/Digital-Research-Source-Code.git
synced 2025-10-26 09:54:20 +00:00
59 lines
2.3 KiB
TeX
59 lines
2.3 KiB
TeX
D I G I T A L R E S E A R C H
|
||
|
||
P. O. Box 579, Pacific Grove, CA 93950, (408) 649-3896
|
||
|
||
|
||
*** MP/M 1.0 ***
|
||
|
||
Application Note #01
|
||
|
||
|
||
Integrating a custom LDRBIOS into MPMLDR.COM
|
||
--------------------------------------------
|
||
|
||
|
||
The MP/M 1.0 loader resides in a file named MPMLDR.COM. This
|
||
loader contains a BIOS called the LDRBIOS org'd at 1700H. MP/M is
|
||
distributed with an MPMLDR.COM that is configured for a four drive
|
||
single density or mixed double/single Intel MDS-800. This MPMLDR.COM
|
||
can be configured for a different hardware environment by coding
|
||
a LDRBIOS as described in section 3.1 of the "MP/M User's Guide".
|
||
|
||
The following steps can be used to integrate a custom LDRBIOS
|
||
into the MPMLDR.COM:
|
||
|
||
1.) Obtain access to CP/M version 1.4 or 2.0 and prepare the
|
||
LDRBIOS.HEX file.
|
||
|
||
2.) Read the MPMLDR.COM file into memory using either DDT
|
||
or SID.
|
||
|
||
A>DDT MPMLDR.COM
|
||
DDT VERS 2.0
|
||
NEXT PC
|
||
1A00 0100
|
||
|
||
3.) Using the input command ('I') specify that the LDRBIOS.HEX
|
||
file is to be read in and then read ('R') in the file. The effect
|
||
of this operation is to overlay the BIOS portion of the MP/M
|
||
loader.
|
||
|
||
-ILDRBIOS.HEX
|
||
-R
|
||
NEXT PC
|
||
1A00 0000
|
||
|
||
4.) Return to the CP/M console command processor (CCP) by
|
||
executing a jump to location zero.
|
||
|
||
-G0
|
||
|
||
5.) Write the updated memory image onto a disk file using
|
||
the CP/M 'SAVE' command. The 'X' placed in front of the file
|
||
name is used simply to designate an experimental version, preserving
|
||
the orginal.
|
||
|
||
A>SAVE 26 XMPMLDR.COM
|
||
|
||
6.) Test XMPMLDR.COM and then rename it to MPMLDR.COM.
|
||
|