Specifications

8254 Programmable Interval Time •• 75
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.