Table of Contents
Procedures for Assembling and Installing non-banked CPM3 for Simple80
The CP/M3 distribution files are compressed with arj.exe. Upload cpm3.arj to Simple80 using XMODEM:
xmodem cpm3.arj /r
decompress with unarj.com:
unarj e cpm3
CP/M3 is now installed on the CF disk.
To install the CPM3 loader, send CPMLDR.HEX in Simple80 monitor and type 'c3' command to install CPM3 loader in track 0 of CF disk. To boot CPM3, type 'b3' command in Simple80 monitor.
Rebuilding CP/M 3 BIOS
There are two programs associated with CP/M3 BIOS, cbios3 and scb. ZMAC is the Z80 assembler for assembling cbios3 and scb. The commands are:
zmac –rel cbios3
zmac –rel scb
The resulting relocatable outputs, cbios3.rel and scb.rel are uploaded to Simple80 via XMODEMl
xmodem cbios3.rel /r
xmodem scb.rel /r
link bios3[os]=cbios3,scb ← create updated BIOS3.SPR
Generate an updated cpm3.sys using gencpm.com
gencpm:
- set to no banked
- N to double allocation vector
- N to hashing for drive A/B/C/D
- Y to overlay data buffer and directory buffer for A/B/C/D
- also share buffers with drive A
Rebuilding CPMLDR
CPMLDR is a barebone disk operating system specifically for loading CP/M. Like CP/M, it also needs a corresponding BIOS to interface to specific hardware. The BIOS is 'ldrbios'. Here is the process of rebuilding CPMLDR with an updated ldrbios:
assemble ldrbios with zmac,
zmac –rel ldrbios
xmodem ldrbios.rel to CP/M environment
xmodem ldrbios.rel /r
Then link ldrbios with cpmldr to higher address such as 0x1100 to avoid conflicting with loading CP/M's CCP
link cpmldr[l1100]=cpmldr,ldrbios
xmodem the resulting cpmldr.com to PC
xmodem cpmldr.com /s
convert it to Intel hex format with offset of 0x1100
bin2hex /o0x1100 cpmldr.com cpmldr.hex
Send cpmldr.hex to Simple80 and use monitor command 'c3' to install cpmldr.