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PS/2 Mouse Interface
Introduction
The PS/2 mouse is a standard interface to both computers and also
many Field Programmable Gate Array (FPGA) development kits.
The protocol is a serial one and in this chapter the basics of the
protocol will be reviewed and also a simple VHDL interface code
to enable the designer to use a mouse, primarily on a standard
FPGA development kit.
PS/2 mouse basics
The origins of the PS/2 mouse are back in the 1980s with the pro-
liferation of the IBM Personal Computer (PC). This had the
generic name of a ‘Personal System’ – hence PS and the second
version of this was therefore called the PS/2 – and the interface
technology has remained under that name ever since.
The PS/2 interface is essentially a custom serial interface with ...