SH7047 Datasheet, PDF (363/764 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTMRISC engine Family/SH7000 Series

TCNT value
H'FF
Overflow
H'00
WT/IT = 1 H'00 written
TME = 1 in TCNT
Time
WOVF = 1 WT/IT = 1 H'00 written
TME = 1 in TCNT
WDTOVF and internal
reset generated
WDTOVF
signal
Internal reset
signal*
WT/IT: Timer mode select bit
TME: Timer enable bit
128 φ clocks
512 φ clocks
Note: * Internal reset signal occurs only when the RSTE bit is set to 1.
Figure 11.2 Operation in Watchdog Timer Mode
11.4.2 Interval Timer Mode
To use the WDT as an interval timer, clear WT/IT to 0 and set TME to 1 in TCSR. An interval
timer interrupt (ITI) is generated each time the timer counter (TCNT) overflows. This function can
be used to generate interval timer interrupts at regular intervals.
TCNT value
H'FF
Overflow
Overflow
Overflow Overflow
H'00
WT/IT = 0
ITI
ITI
ITI
ITI
TME = 1
ITI: Interval timer interrupt request generation
Figure 11.3 Operation in Interval Timer Mode
Time
Rev. 2.00, 09/04, page 323 of 720