Mouse - History
The mouse was orginally a British military secret during the second world war. It was used to interface with radar. In the early 1980's it was a $400+ prototype. Microsoft shipped a mouse with one of their computer in 1983. MAC followed suit in 1994. It took a long time for computer mice to take off because of a lack of support from computer operating systems.
Mouse - Today
Mouse - Hardware
There are two main types of computer mice. The older mechanical type with an actual ball inside the mouse to tack its movements. This type had been supercided by the newer optical type mice which use light based sensors to track moverments.
Newer mice actually have interal computer to run the calucation so it can trasmit less information to the computer and the computer dosen't have to take up it's own memory and time to comprehend what the mouse is doing.
Mouse - Example
Using a simple mechanical two button mouse, I will track how it interacts with a computer through a PS/2 port as seen to the left. I will not be using a modern USB port because that could be an entire presentation on it's own.
The mouse will only use four of the connections. One for power, another for clock, a third for ground, and fourth for the actual data.
It will sent only three bytes. One for the X position, one for the Y position, and a last one. The last one will indicate if the right and left buttons are up or down, whether or not there X or Y overflow, which dircetion the mouse moved, and the last two binary digits aren't used.