RX230 Group, RX231 Group
Initial Settings and Usage Procedure of RTC Battery Backup Function
R01AN4831EJ0100 Rev.1.00
Page 5 of 23
Aug.20.19
Table 1.1 Operating Conditions
VCC/VBATT
State
Voltage
Monitor 0
Reset
(Vdet0)
VBATT Pin
Voltage Drop
Detection
Interrupt
(Vdetvbt)
RTC
Count
Operation
LCD
Display
Data Saved
(RAM, Time
Information)
RTC
Initialization
Input Capture
(1)
(initial state)
Vcc = On (active)
Vbatt = On
No
generated
Enable
Operating
Yes
No
Yes
Enable
(2)
Vcc = On
Off,
Vbatt = On
On
(switch to battery)
Generated
No
Operating
Turn off
Saved
No
Enable
(3)
Vcc = Off,
Vbatt = On
(battery active)
On hold
No
Operating
(No if
VBATT
below
1.8V)
No
Saved
No
Enable
(inputted)
(4)
Vcc = Off
On,
(switch to VCC)
Vbatt = On
Released
No
Operating
Turn on
Saved
No
(Yes if VBATT
below 1.8V
detected)
Enable
(5)
Vcc = On
(VCC active)
Vbatt = On
Not
generated
Enable
Operating
Yes
Saved
No
Enable
(6)
Vcc = On
Vbatt = On
Off
(battery depleted)
Not
generated
Generated
Operating
Yes
Saved
No
Enable