GameBoy Page

options random home screenshot http://www.cs.umd.edu/users/fms/GameBoy/ (World Wide Web Directory, ~04/1995)
Other archives: chipfun

What is GameBoy?

Frequently Asked Questions:

  1. Are there any GameBoy emulators for the personal computers?
    YES, there is a GameBoy-look-alike emulator for the Commodore Amiga called ToyBoy. This emulator can be obtained via FTP from WUARCHIVE or any other AmiNet site.

    [#] Gameboy68000.lha from WUARCHIVE

    Unfortunately, this package is incomplete amd HAS NOTHING TO DO with the real GameBoy. It was stolen from a UK-based company called Argonaut which does hardware and software development for Nintendo. According to Argonaut's managing director Jez San, ToyBoy was an in-house emulator written to see how difficult it would be to program GameBoy games. Since its authors knew nothing about internals of the real GameBoy when they were writing the emulator, ToyBoy is completely incompatible with GameBoy.

  2. Is it possible to build a backlight into GameBoy?
    NO, it is impossible to make a backlight for the reflective LCD. Nevertheless, it is possible to put a light source inside GameBoy so that it will be above the screen. Don't forget that opening GameBoy will void the warranty though.

  3. Are there any game copiers for GameBoy?
    No stand-alone game copiers are known. Nevertheless, there seem to be GameBoy adaptors for MultiGameDoctorII, MultiGameHunter, SuperWildCard and SuperComPro. Also, there is a device allowing to play games stored on credit card-like magnetic cards which is produced in Japan and isn't sold in U.S.

  4. MultiGame cartridges for GameBoy:
    Yes, these cartridges are at least half-illegal because their producers violate copyright law.
    Yes, these things exist for GameBoy. At present time, there are four kinds of them: 48in1, 64in1, 86in1 and 105in1 (although there were rumors about 200in1 and even 1500in1 cartridges. The latter is said to be 15-20 cm long).
    They all seem to contain the same basic set of games most of which are either old Nintendo products (like Alleyway or Tennis) or low-quality games from other companies with a couple of good games added. Number of games in such a cartridge is actually SMALLER than the number written on the box because some games are present in two or three copies (with a number of lives and other things changed). For example, 64in1 cartridge contains only about 48 DISTINCT games. At least 27 of them can be classified as "logic" or "strategy" games. There were many requests to list games multigame cartridges contain. So, here is a list of games how it appears in a menu of a 105in1 cartridge. Other multigame cartridges contain subset of games listed below. Notice the large number of japanese titles and repetitions. There are also some titles which actually correspond to the same game.

  5. Using GameGenie with multigame cartridges:
    No, GameGenie DOES NOT WORK with multigame cartridges.

  6. GameBoy clones:
    There seem to be several GameBoy clones produced in Asia. Two of them are called Sunny and WonderBoy. The only difference is the name printed on the case. This information was supplied by Simon Lai.

  7. Japanese cartridges:
    These are cartridges which are not available in U.S., although you can find them if you are lucky. Following descriptions of japanese cartridges were prepared by Mark Kaufman.
    Parodius [TYPE:Shooter PRODUCER:Konami]
    This is the legendary Japanese shooter to which all others are compared. It is awesome, huge, creative, challenging and fun, fun, fun.
    Twinbee [TYPE:Shooter PRODUCER:Konami]
    Another Japanese cart that should be sold over here. It's better than 90% of all GB games.

  8. Where to get parts to repair GameBoy?
    Mark Kaufman found address of the company selling replacement parts for GameBoy [as well as Sega AC adapters and Atari parts]. Here is their phone number and a list of GameBoy parts they carry:

    MCM Electronics
    TOLL-FREE: 1-800-543-4330
    FAX: 1-513-434-6959
    VOICE: 1-513-434-0031
    M-F: 7AM-8PM EST Sat: 9AM-6PM EST

  9. Some time ago, there was a preview of a 3D vectored game for GB called "Lunar Chase" in Nintendo Power magazine. What happened with this game?
    According to Nintendo, the game was cancelled :(. This information was obtained from Nintendo hotline [1-800-255-3700 in USA].

  10. What is SuperGameBoy?
    The add-on is a cartridge that goes into the game slot. The center has a hole for Game Boy games that allow you to play any game ever created for the GB.
    The SGB allows you to customize games by adding up to 256 colors to sprites. As GameBoys are square and TVs are not, you can create your own border or use pre-installed ones. Borders include: people watching you play as they would a movie, Lemmings trolling around the screen and more. The SGB does not allow you to play Game Link modes of games.
    Future GB games will be programmed with a color palette so you won't have to add colors to the game.
    Spokane, WA (March 15, 1994)

GameGenie Information:

  1. How it works?
    GameGenie allows you to substitute some of the codes in the cartridge ROM with your own codes. For example, you can substitute the default number of lives with your own number. GameBoy GameGenie allows to substitute up to three codes.

  2. Where to get the codes?
    GameBoy GameGenie codes are available through anonymous FTP at
    [#] ftp.netcom.com in directory /pub/vidgames/gamegenie.

  3. What is the meaning of the digits in GameGenie code for GameBoy?
    (all digits are in hexadecimal system)
    GameBoy GameGenie Code: DD2-103-??? It is suspected that the last three digits represent the ROM paging register, but no information is available.

    Example: 3D2-ABF-3BE - Set 3Dh (DEC A command) at address F2ABh

    Some commonly used Z80 instructions with their codes:

    Here, you can also get a
    [#] Complete list of Z80 instructions

  4. Hidden messages in GB GameGenie:
    Press following buttons at the Code Entry Screen:
    1. U D L R
    2. B A L R [SELECT]
    3. U U A B A D D
    4. R U D U L U D U
    5. B A B R L D U
    6. A A A A B B B [START]
    7. R L R L D D U U
    8. A B A B A A [SELECT]
    9. A L L A B R R B
    Taken from Game Player Magazine, May 1994.

  5. CodeMasters' address and phone number:
    Codemasters
    Lower Farm House,
    Southam,
    Warwickshire.
    CV33 0DL
    UK
    Phone: +44 926 814132
    I didn't try calling them. If you get any additional information from CodeMasters, please, email it to me

  6. Why some GameGenie codes don't work?
    Some games exist in several different versions. Although these versions look exactly the same, the actual program codes differ. Therefore, while some GameGenie codes work with one version of the cartridge, they aren't guaranteed to work with other versions.

GameBoy Hardware:

Information about GameBoy's hardware is extremely hard to find. Most of it is incomplete, uncertain and vague. If you have any information [especially about things listed in "Unanswered Questions" section], PLEASE, email it to fms@wam.umd.edu.
  1. GameBoy connector pinouts [not complete]:
    PICTURE

  2. GameBoy circuitry [not complete]:
    PICTURE

  3. GameBoy memory map [speculation]:
    FFFFh ---------------------- Gameboy peripherals Cartridge address frame is filled C000h ---------------------- by 32kB of ROM in small cartridges. In large [>32kB] cartridges it has 16K of internal RAM following structure: READ WRITE 8000h -----------------------------------------------+------------------- | Paged ROM bank | 8kB battery-backed | RAM (if paged in) 4000h - Cartridge address ---------------------------+------------------- frame | Bottom 16kB of ROM +------------------- | Paging Register 0000h -----------------------------------------------+------------------- Paging Register has 5 bits - D0-D4 which represent 32 16kB banks of memory. Bank 0 is battery-backed RAM.

  4. Addresses of GameBoy I/O ports:
    This section was deleted after it appeared that none of information listed in it matches the game disassemblies done by Peter Knight. New section will be done as soon as I get information from him. For now, it appears that all GB I/O ports are located at memory adresses between FF00h and FFFFh.

  5. GameBoy CPU:
    As it appears, the CPU used in GameBoy is not exactly Z80. Some of Z80 instructions and registers are missing. Peter Knight estimates that about 20% of Z80 instructions have been altered.

  6. US Patents related to GameBoy:

People who contributed to this page:

UNANSWERED QUESTIONS:

If you have any information about GameBoy, feel free to send me email to fms@wam.umd.edu.
  1. Meaning of the last three digits of GameGenie code?
  2. Memory Map of GameBoy?
  3. Pinouts of the GameBoy cartridges?
  4. Programming sprites, sound, screen scrolling, serial port?
  5. Connecting GameBoy to TV?
  6. GameGenie codes not listed in the official updates?
  7. Game cheats and passwords?
  8. GameBoy emulators?
  9. Game Copiers for GameBoy?
  10. "Generic" cartridges allowing to use reprogrammable ROM plugged into a socket or even a static RAM?
  11. Pinouts of GameBoy's serial port?
  12. Ports' addresses and their usage?
  13. etc. etc. etc.
Maintained by Marat Fayzullin [fms@wam.umd.edu]