nintendo 64 controllers

Connector / Socket

Console side

Pin	Signal
1	Vcc 3v3
2	Signal
3	Ground

Controller side:

Pin	Signal	Extension cable
1	Ground	Black
2	Signal	White
3	Vcc 3v3	Red

NOTE. Nintendo 64 provides 3.6v.

Protocol

In its idle state the data line is high (3,3v).

Each bit transmitted takes 4μs of time.

value	secuence (4μs)
1	0 1 1 1
0	0 0 0 1

Addressing

The first 11 bits of the two bytes are the address. The next 5 bits are CRC.

CRC

https://code.google.com/archive/p/micro-64-controller/wikis/CRC.wiki

Identify command (0x00)

The controller responds with three bytes to identify itself.

Response

first byte: 0x05
second byte: 0x05 (some: 0x00)
third byte:
- 0x01 if there is a controller pack plugged in.
- 0x02 if there is no controller pack.
- 0x04 if the previous controller read/write address CRC showed an error.

Status command (0x01)

Response

1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17-24	25-32	33
A	B	Z	START	UP	DOWN	LEFT	RIGHT	unused	unused	L	R	C-UP	C-DOWN	C-LEFT	C-RIGHT	X-AXIS	Y-AXIS	stopbit

The stopbit is always "1".

For each button a "1" represents a pressed button, and a "0" means: button released.

Read from expansion bus command (0x02)

Parameters: 2 bytes

addres + crc

Response: 32 bytes

Contents of that address and ends with a data CRC.

Write to expansion bus command (0x03)

Parameters: 2 + 32 bytes

addres + crc + contents

Response: 1

CRC

Reset command (0xFF)

Response: same as 0x00