The Intel (NEC). ADLINK Technology PCI-7200

Appendix A. 8254

Programmable Interval Timer

Note : The material of this section is adopted from

“Intel Microprocessor and Peripheral Handbook Vol. II --Peripheral”

A.1 The Intel (NEC) 8254

The Intel (NEC) 8254 contains three independent, programmable, multi-mode 16 bit counter/timers. The three independent 16 bit counters can be clocked at rates from DC to 5 MHz. Each counter can be individually programmed with 6 different operating modes by appropriately formatted control words. The most commonly uses for the 8254 in microprocessor based system are:

• programmable baud rate generator

• event counter

• binary rate multiplier

• real-time clock

• digital one-shot

• motor control

For more information about the 8254, please refer to the NEC

Microprocessors and peripherals or Intel Microprocessor and

Peripheral Handbook.

8254 Programmable Interval Time

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