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 Clone This Repo

Since incorporating the use of submodules, the process of 'getting everything' requires a command that will recursively download all of the parts like this:

git clone --recurse-submodules https://github.com/Z80-Retro/2063-Z80-cpm.git

or, if you use ssh (useful if you want to push changes to a repo to make a pull request):

git clone --recurse-submodules [email protected]:Z80-Retro/2063-Z80-cpm.git

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

After the clarification of the Digital Research Inc. license in 2022 on the use and distribution of CP/M, all of the files needed to build and run CP/M on the Retro have been made available on github in the Z80-Retro/cpm-2.2 repo.

The CP/M source, utilities, and manuals were collected from the The Unofficial CP/M Web site in 2023:

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

Build and install CP/M

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

Resource Links

• CP/M Manuals

• Individual manual booklets (for the purists):

• The Unofficial CP/M Web site

• 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