DIP-16

 1  2  3  4  5  6  7  8
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|        LOGITECH       |
|      46107Q2 424C     |
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 9 10 11 12 13 14 15 16

1 = clock for device = crap-ass fugly (R-C Clocked probably)

2 = 5V?

3 = GND?

4 = 5V?

5 = Z encoder (Scrollywheel)

6 = Part of Y Encoder

7 = Part of X Encoder

8 = GND

9 = Reference value for Hi/Lo? Seems to be Vcc / 2.5 or something?

10 =

11 =

12 = PS2 DATA

13 = PS2 CLOCK

14 = Right Click

15 = Left Click

16 = Middle Click

Port to PC

 1  2  3  4
 -----------
|Bk O  Bk Y |
 -----------

1 = Gnd from PC

2 = Vcc from PC

3 = Data

4 = Clock