R2025S/D
• Alarm_W Registers (Address 8-Ah)
Alarm_W Minute Register (Address 8h)
D7
D6
D5
D4
D3
D2
D1
D0
-
WM40
WM20
WM10
WM8
WM4
WM2
WM1
(For Writing)
0
0
WM40
Indefinite
WM20
Indefinite
WM10
Indefinite
WM8
Indefinite
WM4
Indefinite
WM2
Indefinite
WM1
Indefinite
(For Reading)
Default Settings *)
Alarm_W Hour Register (Address 9h)
D7
D6
D5
WH20
WP⋅/A
WH20
WP⋅/A
Indefinite
D4
WH10
D3
WH8
D2
WH4
D1
WH2
D0
WH1
-
-
(For Writing)
0
0
0
0
WH10
WH8
WH4
WH2
WH1
(For Reading)
Default Settings *)
Indefinite
Indefinite
Indefinite
Indefinite
Indefinite
Alarm_W Day-of-week Register (Address Ah)
D7
D6
D5
D4
D3
D2
D1
D0
-
WW6
WW5
WW4
WW3
WW2
WW1
WW0
(For Writing)
0
0
WW6
Indefinite
WW5
Indefinite
WW4
Indefinite
WW3
Indefinite
WW2
Indefinite
WW1
Indefinite
WW0
Indefinite
(For Reading)
Default Settings *)
*) Default settings: Default value means read / written values when the PON bit is set to “1” due to VDD
power-on from 0 volts.
* The D5 bit of the Alarm_W Hour Register represents WP/A when the 12-hour mode is selected (0 for a.m.
and 1 for p.m.) and WH20 when the 24-hour mode is selected (tens in the hour digits).
* The Alarm_W Registers should not have any non-existent alarm time settings.
(Note that any mismatch between current time and preset alarm time specified by the Alarm_W registers may
disable the alarm interrupt circuit.)
* When the 12-hour mode is selected, the hour digits read 12 and 32 for 0 a.m. and 0 p.m., respectively. (See
"P11 •Control Register 1 (ADDRESS Eh) (2) /12⋅24: 12-/24-hour Mode Selection Bit")
* WW0 to WW6 correspond to W4, W2, and W1 of the day-of-week counter with settings ranging from (0, 0,
0) to (1, 1, 0).
* WW0 to WW6 with respective settings of 0 disable the outputs of the Alarm_W Registers.
18
RICOH [ RICOH ELECTRONICS DEVICES DIVISION ]
