HD64F38024HV Datasheet, PDF (459/684 Pages) Renesas Technology Corp – Hardware Manual Renesas 8-Bit Single-Chip Microcomputer H8 Family/H8/300L Super Low Power Series

Section 14 Power-On Reset and Low-Voltage Detection Circuits (H8/38124 Group Only)
Bits 6 to 4—Reserved
These bits are read/write enabled reserved bits.
Bit 3—Reference Voltage External Input Select (VREFSEL)
This bit is used to select the reference voltage.
Bit 3
VREFSEL
0
1
Description
The on-chip circuit is used to generate the reference voltage
(initial value)
The reference voltage is input to the Vref pin from an external source
Bit 2—Reserved
This bit is reserved. It is always read as 0 and cannot be written to.
Bit 1—LVD Power Supply Voltage Drop Flag (LVDDF)
This bit indicates when a power supply voltage drop has been detected.
Bit 1
LVDDF
0
1
Description
[Clearing condition]
When 0 is written after reading 1
[Setting condition]
When the power supply voltage drops below Vint(D)
(initial value)
Bit 0—LVD Power Supply Voltage Rise Flag (LVDUF)
This bit indicates when a power supply voltage rise has been detected.
Bit 0
LVDUF
0
1
Description
[Clearing condition]
When 0 is written after reading 1
(initial value)
[Setting condition]
When the power supply voltage drops below Vint(D) while the LVDUE bit in
LVDCR is set to 1, and it rises above Vint(U) before dropping below Vreset1
Rev. 8.00 Mar. 09, 2010 Page 437 of 658
REJ09B0042-0800