arcade-galaga: A VHDL repository from OpenGateware

Namco Galaga Compatible Gateware IP Core

This Implementation of a compatible Galaga arcade hardware in HDL is the work of Dar.

Overview

Galaga is a single-screen shoot-em-up in which the player controls a 'Fighter' spaceship and must defend the home planet against the on-coming hordes of alien invaders called "Galagans". The Fighter can only move left and right along the bottom of the screen.

Galagans fly onto the screen in a variety of formations before forming troop lines at the top of the screen. Once all troop lines are formed the Galagans separate and start attacking the player's Fighter in ones, twos and threes. The top-line Boss Galaga need to be shot twice before they are destroyed.

The Boss Galaga has a tractor beam that can capture the player's Fighter. A captured Fighter changes color from white to red and stays with that particular Boss until it is destroyed. The Fighter can be retrieved by destroying the Boss that captured it, but players must be careful not to destroy the captured Fighter itself, or that Fighter is lost. A rescued Fighter changes color back to white and links up with the player's current Fighter, doubling its fire power.

Technical specifications

Main CPU: Zilog Z80 @ 3.72 MHz
Graphics CPU: Zilog Z80 @ 3.72 MHz
Sound CPU: Zilog Z80 @ 3.72 MHz
Sound Chip: Fujitsu MB8843 and MB8844 @ 1.536 MHz
Resolution: 288×224, 16 colors
Display Box: 384×264 @ 6.144 MHz
Aspect Ratio: 9:7
Orientation: Vertical (90º)

Compatible Platforms

Analogue Pocket

Compatible Games

ROMs NOT INCLUDED: By using this gateware you agree to provide your own roms.

MAME

Game	Region	Status
Galaga (Namco)	JPN	✅
Galaga (Namco rev. B)	JPN	✅
Galaga (Midway set 1)	USA	✅
Galaga (Midway set 1 with Fast Shoot Hack)	USA	✅
Gatsbee (Uchida)	UNK	✅
Nebulous Bee (Unknown)	UNK	❌

HBMAME (HomeBrew MAME)

Game	Status
Galaga (Enduring Freedom)	✅
Galaga (Fast shoot)	✅
Galaga Ghost (Set 1)	✅
Galaga Ghost (Set 2 - 2002-11-28)	✅
Galagalaxian	✅
Galapede (Fast Shoot)	✅
Vector Galaga Fast Shoot	✅
Vector Galaga Midway	✅
Vector Galaga	✅

ROM Instructions

Download ORCA (Open ROM Conversion Assistant)
Download the ROM Recipes and extract to your computer.
Copy the required MAME .zip files into the roms folder.
Inside the tools execute the script related to your system.
1. Windows: right click make_roms.ps1 and select Run with Powershell
2. Linux and MacOS: run script make_roms.sh.
After the convertion is completed, copy the Assets folder to the Root of your SD Card.
Optional: A .sha1 file is included to verify if the hash of the ROMs are valid. (eg: sha1sum -c checklist.sha1)

Note: Make sure your .rom files are in the Assets/galaga/common directory.

Status of Features

WARNING: This repository is in active development. There are no guarantees about stability. Breaking changes might occur until a stable release is made and announced.

Dip Switches
Pause
Hi-Score Save

Known Issues

A bug in the sound CPU program. During initialization, it enables NMI before clearing RAM, but the NMI handler doesn't save the registers, so it cannot interrupt program execution. If the NMI happens before the LDIR that clears RAM has finished, the program will crash.1
Nebulous Bee is stuck at the service screen

Credits and acknowledgment

Powered by Open-Source Software

This project borrowed and use code from several other projects. A great thanks to their efforts!

Modules	Copyright/Developer
Data Loader	2022 (c) Adam Gastineau
Galaga HDL	2016 (c) Dar
Pause Handler	2021 (c) Jim Gregory
T80	2001 (c) Daniel Wallner

Legal Notices

The authors and contributors or any of its maintainers are in no way associated with or endorsed by Bandai Namco Entertainment Inc.

opengateware/arcade-galaga