ubox MSX lib

This is a set of libraries and tools to make MSX games using the C programming language.

There are three main components:

• ubox: thin wrapper around MSX 1 BIOS, focusing on Screen 2 and 32K cartridge ROMs.
• spman: a simple sprite and pattern manager with flickering support.
• mplayer: a wrapper around Arkos 2 AKM player, supporting music and priority based one channel sound effects.

There are also some utilities (e.g. compression), and tools to process data and help you building your games.

The aim is making MSX games in C, without writing Z80 assembler or having a deep knowledge of the system.

Requirements

• GNU Make (others may work)
• a POSIX compatible environment

The SDCC compiler is also needed. Check the following table for some hints on compatibility.

If you want to build the example you will also need:

• python 3
• pillow
• GCC (only the C compiler)
• Disark, one of the tools distributed with Arkos Tracker 2 (download from Arkos Tracker 2 website)

On Windows 10, there are reports of successful builds using:

• latest version of Cygwin64 with package for gcc-core 10.2.0-1
• SDCC 4.0.0
• python 3.9.1

If you want to build the docs you will also need:

• pandoc
• python 3
• pygments
• pandocfilters

Building

To build the libraries run:

make

After a successful build, the libraries should be in ./lib.

The include files are ready to use in ./include.

Add those directories in SDCC's search path and you are ready to go.

Note: make is expected to be run from the root of the repo. The PATH env variable will be set automatically.

Running tests

There are tests that can be run with make test.

Building the example

An example game is included with the libraries and it can be built with:

make game

After a successful build, the game ROM should be in ./bin.

CAS support

Although the focus is cartridge ROMs, CAS files (and audio) is still one of the cheapest ways of loading homebrew games on a real MSX.

Optionally, is possible to generate a CAS file of the example game running:

make game-cas

After a successful build, the game CAS should be in ./bin.

The CAS support has some limitations:

• It requires 32K of extra RAM.
• The compressed ROM must be less than 24576 bytes.
• The loader uses the BIOS, so it won't be fast.
• Machines with disk must have it disabled (by pressing shift on boot), to have more memory available.

Despite these limitations, it is worth considering releasing your game in CAS format as well as cartridge ROM.

Building the docs

The documentation is available at usebox.net, so this is optional.

To build the docs run:

make docs

The reference in HTML format will be generated in ./docs.

Contributing

All contributions are welcome.

If you think you have found a bug, please submit a bug report providing some information:

• What was expected to happen
• What actually happens
• How to reproduce the issue

Some advice if you want to make a successful contribution:

• Be cordial
• Get early feedback, specially when working on a large contribution
• Contributions always require a pull request and a review
• Check the TODO for ideas!

Formatting

This project uses Black to format the Python code, and this is checked in CI.

Before submitting any code to review, ensure you have installed Black 22.1.0 and run:

black .

Authors

This was mostly written by Juan J. Martinez during the development of Night Knight and Uchūsen Gamma.

Other contributors:

• Pedro de Medeiros
• Your name here?

Copying

This software is distributed under MIT license, unless stated otherwise.

See COPYING file.

TL;DR: the only condition is that you are required to preserve the copyright and license notices. Licensed works, modifications, and larger works may be distributed under different terms and without source code; this includes any game made with the help of this software.

Credit is appreciated, but is not a legal requirement. For example: you can add to the game's documentation a note like "This game uses ubox MSX lib".

There are some third party tools included here for convenience and are covered by their own license or are public domain.