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Section 9 Timers
9.1
Overview
The H8/3637 Series provides five timers (timers A, F, G, Y, and watchdog timer) on-chip.
Table 9.1 outlines the functions of timers A, F, G, Y, and watchdog timer.
Table 9.1
Timer Functions
Name
Functions
Internal Clock
Event
Input Pin
Waveform
Output Pin
Remarks
Timer A
8-bit
timer
Interval timer ø/8 to ø/8192
(8 choices)
—
—
Time base
ø
W
/128
(choice of 4
overflow periods)
—
—
Clock output
ø/4 to ø/32,
ø
W
/4 to ø
W
/32
(8 choices)
—
TMOW
Timer F
•
16-bit free-running
timer
•
Event counter
•
Can be used as two
independent 8-bit
timers
•
Output compare
ø/2 to ø/32
(4 choices)
TMIF
TMOFL
TMOFH
Timer G
•
8-bit timer
•
Input capture
•
Interval timer
ø/2 to ø/64, ø
W
/2
(4 choices)
TMIG
—
•
Counter clear
designation
possible
•
Built-in noise
canceller
circuit for input
capture
Timer Y
•
16-bit reload timer
•
Can operate as free-
running timer
•
Event counter function
ø/4 to ø/8192
(7 types)
TMCIY
—
Watchdog
timer
•
Reset signal
generated on 8-bit
counter overflow
ø/8192
—
—