R01UH0823EJ0100 Rev.1.00
Page 167 of 1823
Jul 31, 2019
RX23W Group
8. Voltage Detection Circuit (LVDAb)
8.6
Event Link Output
The LVD can output the event signals to the event link controller (ELC).
(1) Vdet1 passage detection event output
The LVD outputs the event signal when it is detected that the voltage has passed the Vdet1 voltage while both the
voltage detection 1 circuit and the voltage monitoring 1 circuit comparison result output are enabled.
When enabling the LVD’s event link output function, be sure to make settings for enabling the LVD before enabling the
LVD event link function of the ELC. To stop the LVD’s event link output function, be sure to make settings for stopping
the LVD after disabling the LVD event link function of the ELC.
8.6.1
Interrupt Handling and Event Linking
The LVD has the bits to separately enable or disable the voltage monitoring 1 interrupt. When an interrupt source is
generated and the interrupt is enabled by the interrupt enable bit, the interrupt request signal is output to the CPU.
On the contrary, as soon as an interrupt source is generated, the event link signal is output as the event signal to the other
module via the ELC regardless of the state of the interrupt enable bit.
It is possible to output voltage monitoring 1 interrupt in software standby. The event signal for the ELC, however, is
output as follows:
When the event of passing Vdet1 is detected in software standby mode, no event signals are generated for the ELC
because no clock is presented in software standby mode. Since the Vdet1 passage detection flag is preserved,
however, when the supply of the clock is resumed after restoring from software standby mode, the event signal for
the ELC is output according to the state of the Vdet1 passage detection flag.