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==== Table of Contents ====

[[#procedures_for_assembling_and_installing_non-banked_cpm3_for_simple80|Procedures for Assembling and Installing non-banked CPM3 for Simple80]]

[[#rebuilding_cp_m_3_bios|Rebuilding CP/M 3 BIOS]]

[[#rebuilding_cpmldr|Rebuilding CPMLDR]]

====== 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.

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==== Rebuilding CP/M 3 BIOS ====

There are two programs associated with CP/M3 BIOS, cbios3 and scb. [[http://48k.ca/zmac.html|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

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==== 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.