2063-Z80-cpm

A BIOS and build scripts for installing CP/M 2.2 on an SD card for the Z80 Retro! board.

How to Avoid Spoilers!

Starting on 20220304 you can avoid any spoilers while watching my YouTube video playlist that discusses this project by clicking on the Releases/tags link in github and locate the tag that matches the datecode in each video. (Specifically the datecode in the video itself, not the dates that YouTube posts about when the videos are uploaded etc.)

Note that I use datacodes that look like this: YYYYMMDD.n

Sorry I did not think of this before.

SD Card Preparation

A discussion of how to partition an SD card for the Retro! board can be found in ./README-SD.md

Boot a Hello World! app from the SD card

See the code in ./hello to create a program that will load and run from the SD card.

Where to download CP/M

The Unofficial CP/M Web site contains:

• source code of various CP/M releases:
  • We want the link that says: CP/M 2,2 ASM SOURCE code
• Application program binaries that can run on the Retro!
  • We want the link that says: CP/M 2.2 BINARY distribution disk for the Xerox 1800 system

See ./cpm22 for details on downloading and preparing the files for assembly.

Build and install CP/M

See ./retro for details on assembling and installing CP/M onto an SD card.

Resource Links

• Individual manual booklets (for the purists):

  • Introduction to CPM Features and Facilities
  • CP/M 2.0 Guide for CP/M 1.4 Users
  • ED (A Text Editor)
  • DDT (Dynamic Debugging Tool)
  • ASM (An 8080 Assembler)
  • CP/M 2.0 Interface Guide
  • CP/M 2.0 System Alteration Guide
  • CP/M 2.2 System Alteration Guide

• One big book of all the above manuals

  • CP/M 2.x Operating System Manual

• The Unofficial CP/M Web site

• Genuine Internet hearsay evidence that suggests that CP/M can be used in for personal use!

  • http://www.gaby.de/faq.htm#5

• The PC parallel printer interface port pinout and signal meanings

  • https://bixolonusa.com/wp-content/uploads/2016/06/parallel.pdf

• The Humongous CP/M Software Archives

  • http://cpmarchives.classiccmp.org/

• Good stuff from someone writing a BIOS for a retro project with a nice story about what can happen if you don't carefully read the Alteration Guide first!

  • http://cpuville.com/Code/CPM-on-a-new-computer.html

• A discussion of CP/M internal basics

  • https://obsolescence.wixsite.com/obsolescence/cpm-internals

• A simulator that looks impressive:

  • https://www.autometer.de/unix4fun/z80pack/#documentation