This repository contains a collection of C language examples for the Thomson MO5, built with the CMOC compiler and related tools.

The project explores different approaches to C development on the MO5, ranging from pure CMOC usage to hybrid and fully home-made C libraries.

All projects are built using Makefiles, available at multiple levels of the repository.

To build and run the programs, you will need:

• DCMOTO emulator
  http://dcmoto.free.fr/emulateur/index.html

• LWTOOLS (6809/6309 cross-development tools)
  https://www.lwtools.ca/

• CMOC (Motorola 6809 C compiler)
  http://gvlsywt.cluster051.hosting.ovh.net/dev/cmoc.html

⚠️ Note: Some of these websites use HTTP instead of HTTPS.
They are well-known and trusted resources in the retro-computing community.

.
├── Makefile                  # Root Makefile (builds everything)
├── tools/
│   └── BootFloppyDisk/       # BootFloppyDisk tools
├── cmoc-native/
│   ├── Makefile              # Builds all samples
│   ├── key_reader/
│   │   ├── Makefile
│   │   └── src/
│   │       └── main.c
│   └── what_is_your_name/
│       ├── Makefile
│       └── src/
│           └── main.c
├── cmoc-hybrid/
│   ├── Makefile              # Builds all samples
│   ├── libs/
│   ├── key_reader/
│   │   ├── Makefile
│   │   └── src/
│   │       └── main.c
│   ├── what_is_your_name/
│   │   ├── Makefile
│   │   └── src/
│   │       └── main.c
│   └── fusee/
│       ├── Makefile
│       └── src/
│           └── main.c
├── home-made/
│   ├── Makefile              # Builds all samples
│   ├── libs/
│   ├── key_reader/
│   │   ├── Makefile
│   │   └── src/
│   │       └── main.c
│   └── what_is_your_name/
│       ├── Makefile
│       └── src/
│           └── main.c
└── graphic/
    ├── Makefile              # Builds all samples
    ├── libs/
    ├── display_text/
    │   ├── Makefile
    │   └── src/
    │       └── main.c
    └── hello_word/
        ├── Makefile
        └── src/
            └── main.c

The root Makefile can automatically install BootFloppyDisk, which is required to generate bootable disk images for the Thomson MO5.

To install the tools:

make install

This will:

• Clone the BootFloppyDisk repository
• Build the required tools
• Generate BOOTMO.BIN, used during disk image creation

make

Each main directory contains its own Makefile, allowing you to build only the samples inside that directory.

Example:

cd cmoc-native
make

Each sample directory has its own Makefile and a single entry point located in src/main.c.

Example:

cd cmoc-native/key_reader
make

Clean everything from the root:

make clean

Or clean at directory or sample level using the corresponding Makefile.

• Uses only cmoc.h
• No standard C libraries
• Pure CMOC examples

• Uses cmoc.h
• Adds custom libraries to extend missing C features
• Partial implementations of stdio.h and ctype.h

Libraries are located in cmoc-hybrid/libs.

• Does not use cmoc.h
• Fully home-made implementations of stdio.h, ctype.h and string.h

Libraries are located in home-made/libs.

• Use cmoc.h
• Explore graphic features

Each directory (cmoc-native, cmoc-hybrid, home-made) contains the same two sample projects.

• Prompts the user to enter their name
• Displays:

Hello [entered name]

• Waits for a key press
• Displays the character code of the pressed key

• move a rocket (A caracter)
• fuel management

• Explore C programming on the Thomson MO5
• Compare multiple development approaches:
  • CMOC-only
  • CMOC + extended libraries
  • Fully custom C runtime
• Provide small, clear, and educational examples

Detailed explanations about the development environment and toolchain setup used in this project are available on my blog:

• Toolchain and environment setup (DCMOTO, LWTOOLS, CMOC, BootFloppyDisk):
  https://thlg057.github.io/mo5-blog/en/days/day-1-setup/

This article explains step by step how to install and configure the tools required to build and run the examples provided in this repository.

• BootFloppyDisk tools by OlivierP-To8
• Thomson MO5 community and documentation