PS/2 Mouse Interface
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PS/2 mouse commands
The PS/2 mouse has a limited set of commands that are essentially
either button press commands or mouse movement commands.
The standard mouse has a left, middle and right button click com-
mand, and the X and Y movement. The X and Y movements are
tracked using counters, where the value is relative to the previous
value sent by the mouse not the absolute position itself.
PS/2 mouse data packets
The PS/2 mouse sends data in serial packets down a data line and
this is synchronous with a clock line also on the mouse interface.
Each packet consists of 3, 8 bit words where the first word is a con-
figuration word with ...