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== Pokemon Mini I/O Port Overview ==

The Pokemon Mini provides a tri-state 8-bit I/O port.  Each bit is mapped to a different pin, and each has it's own configurable direction, providing a relatively powerful interface to external hardware.

The I/O interface is shared among various parts of hardware, so care must be taken when altering the direction and data as not to disturb other processes.

{| border="1"
|+ '''Pin Mapping'''
! Pin
! Function
|-
| 0
| IR Receiver
|-
| 1
| IR Transmitter
|-
| 2
| EEPROM Data
|-
| 3 
| EEPROM Clk
|-
| 4
| Rumble Motor
|-
| 5
| IR Disable
|-
| 6
| Always 1 (Pull-Up?)
|-
| 7
| (IR Transmitter? Used to double power?)
|}

== How the I/O Port Works ==

The I/O Port is configured using 2 8-bit registers.  IO_DIR selects the data direction of the respective pin.  Reset is an input bit, Set is an output pin.  IO_DATA provides both a input read value as well as the latch to drive output, the value read back from this port depends on the state of IO_DIR.

When a pin is set to input, and there is no data being externally driven on the pin, the state is left undetermined as that bit is defined as floating.

== Hardware ==

The EEPROM is a standard 8KiB EEPROM, using an I2C interface.

Rumble is simply a pin used to drive a motor, which is likely driven through an amplifier.  For rumble to be active, the rumble pin must be set for output with a logical 1 driving the pin.

IR is a standard unmodulated Diode receiver combo.  Setting the IR Disable to output and setting data to logical 1, disables the receiver.