R8C/18 Group, R8C/19 Group
7. Voltage Detection Circuit
Rev.1.30
Apr 14, 2006
Page 44 of 233
REJ09B0222-0130
Figure 7.5
VW1C Register
Voltage Monitor 1 Circuit Control Register
(1)
Symbol
Address
After reset
(2)
VW1C
0036h
Hardw are reset : 0000X000b
Pow er-on reset, voltage monitor 1 reset :
0100X001b
Bit Symbol
Bit Name
Function
RW
NOTES:
1.
2.
3.
Set the PRC3 bit in the PRCR register to 1 (w rite enable) before w riting to this register.
When rew riting the VW1C register, the VW1C2 bit may be set to 1. Set the VW1C2 bit to 0 after rew riting the VW1C
register.
The value remains unchanged after a softw are reset, w atchdog timer reset, or voltage monitor 2 reset.
The VW1C0 bit is enabled w hen the VCA26 bit in the VCA2 register is set to 1 (voltage detection 1 circuit enabled).
Set the VW1C0 bit to 0 (disable), w hen the VCA26 bit is set to 0 (voltage detection 1 circuit disabled).
VW1C7
Voltage monitor 1 reset generation
condition select bit
When the VW1C1 bit is set to 1 (digital filter
disabled mode), set to 1.
RW
VW1C6
Voltage monitor 1 circuit mode
select bit
When the VW1C0 bit is set to 1 (voltage
monitor 1 reset enabled), set to 1.
RW
—
(b3)
Reserved bit
VW1F1
RW
Sampling clock select bits
b5 b4
0 0 : fRING-S divided by 1
0 1 : fRING-S divided by 2
1 0 : fRING-S divided by 4
1 1 : fRING-S divided by 8
VW1F0
RW
When read, the content is undefined.
RO
0 : Digital filter enabled mode
(digital filter circuit enabled)
1 : Digital filter disabled mode
(digital filter circuit disabled)
RW
VW1C2
Reserved bit
VW1C1
Voltage monitor 1 digital filter
disable mode select bit
VW1C0
RW
Voltage monitor 1 reset enable
bit
(3)
0 : Disable
1 : Enable
b7 b6 b5 b4 b3 b2
Set to 0.
RW
b1 b0
0