Renesas F-ZTAT H8 Series, Hardware Manual

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9. Timers
Rev.3.00 Jul. 19, 2007 page 220 of 532
REJ09B0397-0300
9.3.4 Timer B Operation States
Table 9.7 summarizes the timer B operation states.
Table 9.7 Timer B Operation States
Operation Mode
Reset
Active
Sleep
Watch Sub-
active Sub-
sleep
Standby
TCB Interval Reset Functions Functions Halted Halted Halted Halted
Auto reload Reset Functions Functions Halted Halted Halted Halted
TMB Reset Functions Retained Retained Retained Retained Retained
9.4 Timer C (H8/3857 Group Only)
9.4.1 Overview
Timer C is an 8-bit timer that increments or decrements each time a clock pulse is input. This
timer has two operation modes, interval and auto reload.
Timer C is a function of the H8/3857 Group only, and is not provided in the H8/3854 Group.
Features
The main features of timer C are given below.
•
Choice of seven internal clock sources (
φ
/8192,
φ
/2048,
φ
/512,
φ
/64,
φ
/16,
φ
/4,
φ
W
/4) or an
external clock (can be used to count external events).
•
An interrupt is requested when the counter overflows.
•
Can be switched between up- and down-counting by software or hardware.
•
When
φ
W
/4 is selected as the internal clock source, or when an external clock is selected, timer
C can function in subactive mode and subsleep mode.