
7.4 Register Settings
7.4.1
Setting procedure when the operation mode is set to generate voltage detection
interrupt request signals
When the operation mode is set to generate voltage detection interrupt request signal, make the following
setting:
In this case, setting VDCR2<SRSS> allows STOP mode to be released when the supply voltage (VDD) be-
comes equal to or higher than the detection voltage (VDxLVL).
1. Clear the voltage detection circuit interrupt enable flag to "0".
2. Set the detection voltage at VDCR1<VDxLVL>(x=1 to 2).
3. Clear VDCR2<VDxMOD> to "0" to set the operation mode to generate voltage detection interrupt
request signals.
4. Set VDCR2<VDxEN> to "1" to enable the voltage detection operation.
5. Wait for 5 [μs] or more until the voltage detection circuit becomes stable.
6. Make sure that VDCR1<VDxSF> is "0".
7. Clear the voltage detection circuit interrupt latch to "0" and set the interrupt enable flag to "1" to enable
interrupts.
Note:If the set value of detection voltage (VDxLVL) is close to the supply voltage (VDD), voltage detection
request signals may be generated frequently. At the return from the voltage detection interrupt process-
ing, execute appropriate wait processing depending on fluctuations in the system power supply and clear
the interrupt latch.
To disable the voltage detection circuit while it is enabled with the voltage detection interrupt request, make
the following setting:
1. Clear the voltage detection circuit interrupt enable flag to "0".
2. Clear VDCR2<VDxEN> to "0" to disable the voltage detection operation.
Note:If the voltage detection circuit is disabled without clearing interrupt enable flag, unexpected interrupt
request may occur.
7.4.2
Setting procedure when the operation mode is set to generate voltage detection
reset signals
When the operation mode is set to generate voltage detection reset signals, make the following setting:
1. Clear the voltage detection circuit interrupt enable flag to "0".
2. Set the detection voltage at VDCR1<VDxLVL>(x=1 to 2).
3. Clear VDCR2<VDxMOD> to "0" to set the operation mode to generate voltage detection interrupt
request signals.
4. Set VDCR2<VDxEN> to "1" to enable the voltage detection operation.
5. Wait for 5 [μs] or more until the voltage detection circuit becomes stable.
6. Make sure that VDCR1<VDxSF> is "0".
7. Clear VDCR1<VDxF> to "0".
8. Set VDCR2<VDxMOD> to "1" to set the operation mode to generate voltage detection reset signals.
Note 1: VDCR1 and VDCR2 are initialized by a power-on reset or an external reset input only. If the supply voltage
(VDD) becomes lower than the detection voltage (VDxLVL) in the period from release of the voltage detection
reset until clearing of VDCR2<VDxEN> to "0", a voltage detection reset signal is generated immediately.
Note 2: The voltage detection reset signals are generated continuously as long as the supply voltage (VDD) is lower
than the detection voltage (VDxLVL).
To disable the voltage detection circuit while it is enabled with the voltage detection reset, make the following
setting:
TMP89FH42
Page 89
RA003