The NEC IR transmission protocol decoding circuit.
The protocol
* a 9ms leading pulse burst (16 times the pulse burst length used for a logical data bit)
* a 4.5ms space
* the 8-bit address for the receiving device
* the 8-bit logical inverse of the address
* the 8-bit command
* the 8-bit logical inverse of the command
* a final 562.5µs pulse burst to signify the end of message transmission.
System clock 50Mhz
Tested on a Altera DE0 Nano Board.
Repeat codes are yet to be implemented.