Timer F; Overview - Hitachi H8/3637 Hardware Manual

9.3

Timer F

9.3.1

Overview

Timer F is a 16-bit timer with an output compare function. Compare match signals can be used to
reset the counter, request an interrupt, or toggle the output. Timer F can also be used for external
event counting, and can operate as two independent 8-bit timers, timer FH and timer FL.
Features: Features of timer F are given below.
• Choice of four internal clock sources (ø/32, ø/16, ø/4, ø/2) or an external clock (can be used as
an external event counter).
• Output from pin TMOFH is toggled by one compare match signal (the initial value of the
toggle output can be set).
• Counter can be reset by the compare match signal.
• Two interrupt sources: counter overflow and compare match.
• Can operate as two independent 8-bit timers (timer FH and timer FL) in 8-bit mode.
Timer FH
 8-bit timer (clocked by timer FL overflow signals when timer F operates as a 16-bit timer).
 Choice of four internal clocks (ø/32, ø/16, ø/4, ø/2).
 Output from pin TMOFH is toggled by one compare match signal (the initial value of the
toggle output can be set).
 Counter can be reset by the compare match signal.
 Two interrupt sources: counter overflow and compare match.
Timer FL
 8-bit timer/event counter
 Choice of four internal clocks (ø/32, ø/16, ø/4, ø/2) or event input at pin TMIF.
 Output from pin TMOFL is toggled by one compare match signal (the initial value of the
toggle output can be set).
 Counter can be reset by the compare match signal.
 Two interrupt sources: counter overflow and compare match.
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