Renesas R8C/20 User Manual

R8C/20 Group, R8C/21 Group 6. Voltage Detection Circuit
Rev.2.00 Aug 27, 2008 Page 33 of 458
REJ09B0250-0200
Figure 6.6 VW2C Register
Volta
g
e Monitor 2 Circuit Control Re
g
ister
(1)
Symbol Address After Reset
(8)
VW2C 0037h 00h
Bit Symbol Bit Name Function RW
NOTES:
1.
2.
3.
4.
5.
6.
7.
8.
9.
b3 b2
0 : Not detected
1 : Vdet2 pass detected
RW
b1 b0b7 b6 b5 b4
VW2C0 RW
Voltage monitor 2 interrupt/reset
enable bit
(6)
0 : Disable
1 : Enable
0 : Digital filter enabled mode
(digital filter circuit enabled)
1 : Digital filter disabled mode
(digital filter circuit disabled)
RW
VW2C2
Voltage change detection
flag
(3,4,8)
VW2C1
Voltage monitor 2 digital filter
disabled mode select bit
(2)
VW2C3
WDT detection flag
(4,8)
VW2F1 RW
Sampling clock select bits
b5 b4
0 0 : fOCO-S divide-by-1
0 1 : fOCO-S divide-by-2
1 0 : fOCO-S divide-by-4
1 1 : fOCO-S divide-by-8
VW2F0 RW
0 : Not detected
1 : Detected
RW
VW2C6
Voltage monitor 2 circuit mode
select bit
(5)
0 : Voltage monitor 2 interrupt mode
1 : Voltage monitor 2 reset mode
RW
VW2C7
Voltage monitor 2 interrupt/reset
generation condition select
bit
(7,9)
0 : When VCC reaches Vdet2 or above
1 : When VCC reaches Vdet2 or below
RW
When the VW2C6 bit is set to 1 (voltage monitor 2 reset mode), set the VW2C7 bit to 1 (w hen VCC reaches to Vdet2
or below ) (do not set to 0).
Set the PRC3 bit in the PRCR register to 1 (enables w riting) before w riting to the VW2C register. When w riting the
VW2C register, the VW2C2 bit may be set to 1. Set the VW2C2 bit to 0 after w riting the VW2C register.
When the voltage monitor 2 interrupt is used to exit stop mode and to return again, w rite 0 to the VW2C1 bit before
w riting 1.
This bit is enabled w hen the VCA27 bit in the VCA2 register is set to 1 (voltage detection 2 circuit enabled).
Set this bit to 0 by a program. When w riting 0 by a program, it is set to 0 (it remains unchanged even if it is set to 1).
This bit is enabled w hen the VW2C0 bit is set to 1 (voltage monitor 2 interrupt/enables reset).
The VW2C0 bit is enabled w hen the VCA27 bit in the VCA2 register is set to 1 (voltage detection 2 circuit enabled).
Set the VW2C0 bit to 0 (disable) w hen the VCA27 bit is set to 0 (voltage detection 2 circuit disabled).
The VW2C7 bit is enabled w hen the VW2C1 bit is set to 1 (digital filter disabled mode).
The VW2C2 and VW2C3 bits remain unchanged in the softw are reset, w atchdog timer reset and voltage monitor 2
reset.

Renesas R8C/20 Specifications

General

Brand	Renesas
Model	R8C/20
Category	Control Unit
Language	English