Programmable Interval Timer- 8254

The 8254 is a programmable interval timer/counter designed for use with Intel microcomputer systems.It is a general purpose, mulch-timing element that can be treated as an array of I/O ports in the system software.The 8254 solves one of the most common problems in any microcomputer system, the generation of accurate time delays under software control. Instead of setting up timing loops in software, the programmer configures the 8254 to match his requirements and programs one of the counters for the desired delay.
After the desired delay, the 8254 will interrupt the CPU. Software overhead is minimal and variable length delays can easily be accommodated.

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