128 KBytes of Flash ROM.
2 KBytes of volatile RAM. The RAM can be made non volatile by adding a 3V battery inside the cart.
The double sided PCB has a gold plated edge connector and is tinned over the rest of its surface. It does *not* have any resist (green paint). This makes life a bit easier for hardware designers who therefore do not risk damaging the PCB while trying to scrape off the resist.
Built in I/O ports
A built in female DB25 connector has 5 Bi-directional lines, 5 Output and 4 Input (all TTL) under user program control.
+5V from the Game Boy is also present but you should use this with great care to avoid damaging either your Game Boy or your GatesBoy™. In any case, you should not draw more than 10 mA.
Program (ROM) Download
The female DB25 connector is also used to program the GatesBoy™ Cartridge via the Parallel Port of an IBM PC.
We wanted to provide developers with the lowest possible startup costs, so we eliminated the need (and cost) of a special programmer to program the cart. All the many features of the GatesBoy™ cart are programmed via the Parallel Port of an IBM PC.
You will need a Parallel Port cable with a 25 pin male connector at
each end. If you want to make your own, connect pins 2-9 and 11-19 at one
end to the same pin numbers at the other end. If all 25 pins are connected
that is also fine.
The download cable is not supplied.
The GatesBoy™ cartridge case is in translucent plastic. There is plenty of empty space in the case to mount your custom hardware. The case is designed with openings for a DB25 connector and a slot for either a SmartMedia card or through which you can pass a ribbon cable to connect to the outside world.
Rapid hardware development
The GatesBoy™ cartridge has an internal bus. Provision is made for mounting a SmartMedia Card connector. and two plug-in Daughter Boards on the main PCB Mother Board.
No SmartMedia Card Interface is supplied with the GatesBoy™ cartridge
However, the Mother Board PCB has provision for mounting a SmartMedia Card connector. In addition, there is a slot in the plastic case designed to take a SmartMedeia Card. One possibility is to use a second 3.3V processor on a Daughter Board in a circuit that you design and build yourself, to interface to a SmartMedia Card.
Rapid software development using free tools
Jeff's GB programming site has an extensive range of software tools ranging from Assemblers, C Compilers, Jeff's GB Basic, Tutorials, Graphic and music utilities. It is also a good source of GB development news and job opportunities.