Genesis Controller Data
This file originally from Neal Patrick Howland. We've completely rewritten it to be more concise, but he did all the hard work. =)
First some background info: The chip inside the controller is a 74HC157. This is a high-speed cmos quad 2-line to 1-line multiplexer. Basically how this works is there are two inputs ( A and B ) for every output ( Y ). There are four groups like this. There is one select signal for the whole chip. When the select signal is low, the output ( Y ) is the same as input A. When the select signal is high, the output Y is the same as input B.
[DB-9 plug]
Pin Description
1 Up
2 Down
3 Chip 4
4 Chip 7
5 +5v
6 Chip 9
7 Chip 1
8 Ground
9 Chip 12
[8 Pin Chip]
[8 Pin Chip] 
	Pin 1 - Select	Pin 16 - Vcc (+5V)
	Pin 2 - 1A	Pin 15 - ENABLE (Ground)
	Pin 3 - 1B	Pin 14 - 4A
	Pin 4 - 1Y	Pin 13 - 4B
	Pin 5 - 2A	Pin 12 - 4Y
	Pin 6 - 2B	Pin 11 - 3A
	Pin 7 - 2Y	Pin 10 - 3B
	Pin 8 - Gnd	Pin 9  - 3Y

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