C8254 Datasheet, PDF (1/6 Pages) List of Unclassifed Manufacturers – PROGRAMMABLE TIMER /COUNTER MEGAFUNCTION

C8254
Programmable
Timer/Counter Megafunction
Introduction
The C8254 programmable interval timer/counter megafunction is a high-performance device, which is
designed to solve the common timing control problems in microcomputer system design. It provides three
independent 16-bit counters, and each counter may operate in a different mode. All modes are software
programmable. Six programmable timer modes allow the device to be used as an event counter, elapsed time
indicator, programmable one-shot, and in many other applications.
Symbol
ADDR[1:0]
DIN[7:0]
CSN
RDN
DOUT[7:0]
WRN
OUT0
CLK0
OUT1
GATE0
OUT2
CLK1
GATE1
CLK2
GATE2
RESETN _C8254
Applications
The six programmable timer modes allow the
C8254 to be used in applications requiring event
counters, elapsed time indicators, and
programmable one-shots among others.
Features
• Three Independent 16-bit Counters
• Status Read-Back Command
• Counter Latch Command
• Read/Write LSB only or MSB only or LSB
first then MSB
• Six Programmable Counter Modes
o Interrupt on Terminal Count
o Hardware Retriggerable One-Shot
o Rate Generator
o Square Wave Mode
o Software Triggered Strobe
o Hardware Triggered Strobe
(Retriggerable)
• Binary or BCD Counting
• Also available in VHDL or Verilog
• Functionality based on the INTEL 8254
CAST, Inc.
March 2004
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