Embedded Technologies, Inc.

8254 Programmable Timer


8254 Programmable Timer is used for timing control applications in microcomputer systems. The design is capable of generating accurate time delays under software control.

Product Specifications
  • Three independently operated 19-bit counters
  • Binary/BCD count operation
  • Multiple Latch command for easy monitoring
  • Counter Latch command
  • Six count modes available for each counter

    • Interrupt at the End of the Count
    • GATE Retriggerable One-Shot
    • Rate Generator
    • Square Wave Generator
    • Software-Triggered Strobe
    • Re-triggerable Hardware-Triggered Strobe


  • Compatible to 8254 and uPD71054
  • Timers can be configured to operate in one of the six operating modes supported.