HD64F38024HV Datasheet, PDF (304/684 Pages) Renesas Technology Corp – Hardware Manual Renesas 8-Bit Single-Chip Microcomputer H8 Family/H8/300L Super Low Power Series

Section 9 Timers
Program process
Interrupt request
flag clear
(2)
Interrupt request
flag clear
Interrupt
Interrupt
Normal
φ_W
Interrupt factor
generation signal
(Internal signal,
nega-active)
Overflow signal,
Compare match signal
(Internal signal,
nega-active)
Interrupt request flag
(IRRTFH, IRRTFL)
(1)
Figure 9.7 Clear Interrupt Request Flag when Interrupt Factor Generation Signal is Valid
Timer Counter (TCF) Read/Write
When φw/4 is selected as the internal clock in active (high-speed, medium-speed) mode, write on
TCF is impossible. And, when read TCF, as the system clock and internal clock are mutually
asynchronous, TCF synchronizes with synchronization circuit. This results in a maximum TCF
read value error of ±1.
When read/write TCF in active (high-speed, medium-speed) mode is needed, please select internal
clock except for φw/4 before read/write.
In subactive mode, even φw/4 is selected as the internal clock, normal read/write TCF is possible.
Rev. 8.00 Mar. 09, 2010 Page 282 of 658
REJ09B0042-0800