Renesas H8S/2111B 用户手册

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Rev. 1.00, 05/04, page 230 of 544 
 
11.4.3 
RESO Signal Output Timing 
When TCNT overflows in watchdog timer mode, the OVF bit in TCSR is set to 1. When the 
RST/
NMI bit is 1 here, the internal reset signal is generated for the entire LSI. At the same time, 
the low level signal is output from the 
RESO pin. The timing is shown in figure 11.5. 
φ
TCNT
H'FF
H'00
132 states
518 states
Overflow signal
(internal signal)
OVF
RESO signal
Internal reset
signal
 
Figure 11.5   Output Timing of 
RESO signal 
11.5 Interrupt 
Sources 
During interval timer mode operation, an overflow generates an interval timer interrupt (WOVI). 
The interval timer interrupt is requested whenever the OVF flag is set to 1 in TCSR. OVF must be 
cleared to 0 in the interrupt handling routine. 
When the NMI interrupt request is selected in watchdog timer mode, an NMI interrupt request is 
generated by an overflow. 
Table 11.2  WDT Interrupt Source 
Name 
Interrupt Source 
Interrupt Flag 
WOVI 
TCNT overflow OVF