The Nintendo GameCube Memory Card slot is a 12-pin proprietary connector introduced with the GameCube console in 2001. It uses Nintendo’s EXI (External Interface) bus — a proprietary serial protocol distinct from standard SPI — operating at clock speeds up to 27 MHz. Cards store game save data in flash memory with a capacity of 512 KB (4 Mbit), organised into 8 KB erasable sectors and 128-byte writable pages. Two memory card slots (Slot A and Slot B) are present on the console, each with an independent SENSE line pair that detects card insertion.
| Pin | Name | Description |
|---|---|---|
| 1 | Sense | Connects to pin 12 |
| 2 | GND | Ground |
| 3 | INT | |
| 4 | 3.3v | |
| 5 | MOSI | Data In |
| 6 | 5v | |
| 7 | MISO | Data Out |
| 8 | 3.3v | |
| 9 | CS | |
| 10 | GND | Ground |
| 11 | CLK | Clock |
| 12 | Sense | Connects to pin 1 |
Notes
- The connector is a Nintendo-proprietary design with no publicly released mechanical specification.
- The EXI bus used by the memory card is not electrically compatible with standard SPI; SPI devices cannot be used directly in this slot.
- Flash memory timing: sector erase 200 ms typical / 1,600 ms maximum; page write 2 ms typical / 60 ms maximum.
- The 5 V rail (pin 6) is present but the card logic operates at 3.3 V; the 5 V line is not used by standard memory cards.
- SENSE pins 1 and 12 are shorted together inside the card body; the console detects insertion by continuity between these two pins.
Signals
- Sense — Card-detection line; pins 1 and 12 are bridged inside the card, allowing the console to detect insertion.
- GND — Ground (pins 2 and 10).
- INT — Interrupt line; the card asserts this line to signal the completion of a flash operation.
- 3.3 V — 3.3 V logic supply (pins 4 and 8).
- MOSI — Serial data into the card (SO in EXI terminology); carries commands and write data from the console.
- 5 V — 5 V supply rail present on the connector; not used by standard memory cards.
- MISO — Serial data out of the card (SI in EXI terminology); carries read data and status responses to the console.
- CS — Chip Select; asserted by the console to address the card on the EXI bus.
- CLK — Serial clock; up to 27 MHz.
References
- Nintendo GameCube Memory Card Guidelines 2.1 — Nintendo Technology Development, 2002