pcmouse.htm
PC mouse information
"This documents tries to tell how PC mouse hardware works and how to read it at the lowest level."
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ps2interface.htm
The PS/2 Mouse Interface 
Describes how to communicate with the mouse using a PS2 controller.
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mouse1.pdf
Synaptics TouchPad Interface Guide
This guide describes how computers and other hosts interface to the Synaptics TouchPad.
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mouse2.pdf
Active PS/2 Multiplexing
Not much use for someone writing an Operating System, but does contain a good breif description of the keyboard controller and mouse commands.  
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