Game Pak

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Available in Nintendo GBA, GBA SP, DS & DS Lite.

Contents

Pinout

32pin cartridge slot. The cartridge bus may be used for both CGB and GBA game paks. In GBA mode, it is used as follows:

Pin Name Dir Description
1 VDD Arrowl.png Power Supply 3.3V DC
2 PHI Arrowl.png System Clock (selectable none, 4.19MHz, 8.38MHz, 16.78MHz)
3 /WR Arrowl.png Write Select
4 /RD Arrowl.png Read Select
5 /CS Arrowl.png ROM Chip Select
6-21 AD0-15 Arrowlr.png lower 16bit Address and/or 16bit ROM-data (see below)
22-29 A16-23 Arrowlr.png upper 8bit ROM-Address or 8bit SRAM-data (see below)
30 /CS2 Arrowl.png SRAM Chip Select
31 /REQ Arrowr.png Interrupt request (/IREQ) or DMA request (/DREQ)
32 GND Arrow.png Ground 0V

Note: Direction is cartridge relative Game Boy.

When accessing game pak SRAM, a 16bit address is output through AD0-AD15, then 8bit of data are transferred through A16-A23.

When accessing game pak ROM, a 24bit address is output through AD0-AD15 and A16-A23, then 16bit of data are transferred through AD0-AD15. The 24bit address is formed from the actual 25bit memory address (byte-steps), divided by two (halfword-steps).

8bit-Gamepak-Switch (GBA, GBA SP only) (not DS) A small switch is located inside of the cartridge slot, the switch is pushed down when an 8bit cartridge is inserted, it is released when a GBA cartridge is inserted (or if no cartridge is inserted). The switch mechanically controls whether VDD3 or VDD5 are output at VDD35; ie. in GBA mode 3V power supply/signals are used for the cartridge slot and link port, while in 8bit mode 5V are used. The current state of the switch can be determined GBA mode via Port 204h (WAITCNT), if (and only if) the switch is pushed, then CGB mode can be activated via Port 000h (DISPCNT.3). The GBA boot procedure in BIOS uses this to detect 8bit carts and to set the GBA into 8bit mode. In 8bit mode, the cartridge bus works much like for GBA SRAM, however, the 8bit /CS signal is expected at Pin 5, while GBA SRAM /CS2 at Pin 30 is interpreted as /RESET signal by the 8bit MBC chip (if any). In practice, this appears to result in 00h being received as data when attempting to read-out 8bit cartridges from inside of GBA mode.

Compatibility

Game Pak type
Original Dual Mode Game Boy Color Only Game Boy Advance Only
Game Boy OK OK - -
Game Boy Pocket OK OK - -
Game Boy Color OK OK OK -
Game Boy Advance / Game Boy Advance SP OK OK OK OK
Nintendo GameCube Game Boy Player OK OK OK OK
Game Boy Micro - - - OK
Nintendo DS / Nintendo DS Lite - - - OK

Size

Original Dual Mode Game Boy Color Only Game Boy Advance Only
Color      
Grey Black Clear
Size 5.8 x 6.5 cm  ? x ? cm

Contributions

Sources