GameBoy FAQs

I need more information on X. Can you post it?



 Most all info I have for GameBoy I have posted. Anything I don't

have posted you can possibly get from my 'Links' web page.





Where can I find some programming

information for the GameBoy, GBC, or SGB?



 Check Marc Rawer's GB page on my 'Links' web page.





Do you know where I can find programming or other

info on the GB Printer or GB Camera ? Or have you

heard of anyone interfacing these to a PC ?



 I have no idea & no. It is possible, though, to read the RAM

on the GB Camera and save this to disk using ReadPlus v3.2 or

later software. To do this you need CARTIO hardware with pin 2

of the GB cart connector (on the programmer) connected to ground.

The 30 photos in the resulting .sav file may be viewed with

GB Camera Dump (for win95) or similar programs. 





Can I use the GameBoy-to-Parallel Port cable to download

games or rom images to my GameBoy?



 No. When you turn your GameBoy on, it has no idea that there is

a cable plugged into it. It is the job of custom software on the

GameBoy to make use of this cable. Only GB Basic currently supports

this cable.





Can I use the GameBoy-to-Parallel Port cable to copy

games or rom images to my PC?



 No. When you turn your GameBoy on, it has no idea that there is

a cable plugged into it. It is the job of custom software on the

GameBoy to make use of this cable. Only GB Basic currently supports

this cable.





I want a programmable cartridge for GameBoy

that I can use to try ROMs. Where do I get one?



Bung - Flash carts & cart programmers

Hong Kong distributor for Bung products

Another Hong Kong distributor for Bung products

Belgium distributor for Bung products

USA distributor for Bung products

UK distributor for Bung products





I want to build a simple cartridge and can program

an EPROM myself. How do I go about doing it?



 I'd recommend getting a cartridge for GameBoy that

contains a ROM, RAM, battery-backed SRAM, and MBC1

bank-switching circuits. Replace the ROM with your own

EPROM. Any size EPROM can be used up to a 4Mbit EPROM.

You may not need all of this other stuff but it is the

most versatile and should support anything you wish to do.



 Examples of these cartridges include: Donkey Kong,

Donkey Kong Land, Donkey Kong Land 2, FFL 2, FFL 3,

Kirby Blockball, Kirby Dreamland II, Kirby Star Stacker,

Lucle, Mario's Picross, Metroid II, Mole Mania, Super Mario

Land II: 6 Golden Coins, Super Mario Land III: WarioLand,

World Cup USA 94, Vegas Stakes, Zelda, and others.





Is there a simpler way of connecting an EPROM to GameBoy?

Do you really need all that extra stuff?



 Any EPROM up to 256Kbits may be used alone connected to

the cartridge pins as shown in the GameBoy Power & 

Cartridge Schematic. If you want to use a larger EPROM

then you'll need an MBC1 (proprietary Nintendo part) chip

or an MBC1 Circuit Equivalent in order to

bank-switch larger chips into GameBoy memory space.





Could you give explicit instructions for removing

a ROM from a cartridge and installing an EPROM?



 The problem here is that different cartridges have different

ROMS with different packages and pinouts. I don't have the time

to try to document every possible cartridge and how it should

be modified. Once you remove the old ROM, you can figure out what

most of the pads under that ROM were used for by tracing them

to the cartridge edge connector.





What steps are needed to compile a program to run

on VGB or the real GameBoy?



 The file size must 32768 or a doubling multiple thereof.

(i.e. 32768,65536,131072,262144, or 524288) The complement

byte must be calculated. The checksum should be calculated

for some GB emulators even though the real GameBoy ignores

this value. (You can use RGBFIX.EXE in the RGBDS Assembler

package to calculate all of these.) For an example of all

of these steps, download GB Basic Source Code.





I've heard about a Super Smart Card

programmable cart for GameBoy. Where

can I order one ?



 They are no longer produced by China Coach Limited.





How much power is required by the GameBoy?



 Total current for a cartridge & a full-size GameBoy are

listed below:



     Cartridge       Size   Current



     Tetris        256kbit   57mA

     F1Race          1mbit   61mA

     DoubleDragonII  1mbit   61mA

     WarioLand       4mbit   64mA

     SuperSmartCard  4mbit  105mA





How is the Pocket GameBoy different than GameBoy?



 It's all cosmetic differences. Electrically and software

wise they are identical. Even the game link port is identical

even though it uses a physically smaller connector. With the

proper adapter, you can connect these different systems. The

only place I know of to get this adapter is through Nintendo.





I would like to use the external link port to control

external RS-232 devices or hookup an IBM-PC keyboard

directly.  Do you have info on this?



 The external link port on the GameBoy is a serial port but

it is NOT compatible with any known serial format. Direct

control of the output pins and reading of the input pins also

is not possible on this port because of the design. There are

example circuits on my web pages that show how to do I/O with

this port.





Is it possible to somehow hook up a GameBoy to a TV?



 It is possible and has been done. Many people have seen these

as the demo machines that are often found where GameBoys are sold.

These are no longer made but they were know as Demo Boy II's.

There is no further information available on this device.



 The main problem is that the horizontal sync in the GameBoy is

~9.2KHz where TVs require ~15.7KHz. This lower frequency sync can

possibly overheat & burnout components of a standard TV. So there

is no simple circuit for connecting a GameBoy to a TV.



 No hobbiest has designed any circuit to connect a GB to a TV.

If they have then they certainly haven't shared it.





I'd like to drive the GameBoy LCD with my own electronics.

Do you have any info on how to do this?



 It is possible but complicated. The LCD interface to GameBoy is

very similar to other large screen LCDs in that a CRT controller

is really required. The reason for this is that all 23,040 pixels

(160x144) have to be written or "refreshed" 60 times a second the

same way that a TV has to constantly redraw or else there won't

be any picture. This is required even if what your trying to display

is static and never changes. This is all the info I have at the

moment.





What schematic layout program do you use? I need one.



 If you need a schematic layout program you might tryProtel. They

have a free EasyTrax program for DOS and the demo version of

of their Windows version online. The Windows version doesn't

allow you to save a drawing but you CAN save changes made to

the libraries. I know one person that drew his whole schematic

inside of a library macro.



 I personally use a very old version of Orcad that is DOS based

and a pain to convert to GIF format. Unfortunately it isn't

public domain so I can't share it.





I notice you have many schematics on your web page but

little or no documents on what they are for. Explain?



 The schematics for the GameBoy and Super GameBoy are just for

curiosity sake. There is no other reason they are there. The other

schematics assume that you have some level of engineering background

and that you can figure out how they might or might not be useful

to you.