RS5C348A RICOH Co.,Ltd., RS5C348A Datasheet - Page 19

• Manufacturer Part Number: RS5C348A
• Description: 4-wire Serial Interface Real-time Clock
• Manufacturer: RICOH Co.,Ltd.

Rev.2.01
Alarm_W Minute Register (Address 8h)
Alarm_W Hour Register (Address 9h)
Alarm_W Day-of-week Register (Address Ah)
D7
-
0
0
D7
-
0
0
D7
-
0
0
Alarm_W Registers (Address 8-Ah)
cause neither an increment nor decrement of time counts.
Example:
When the second digits read 00, 20, or 40, the settings of "0, 0, 0, 0, 1, 1, 1" in the F6, F5, F4, F3, F2, F1,
and F0 bits cause an increment of the current time counts of 32768 by (7 - 1) x 2 to 32780 (a current time
count loss). When the second digits read 00, 20, or 40, the settings of "0, 0, 0, 0, 0, 0, 1" in the F6, F5, F4,
F3, F2, F1, and F0 bits cause neither an increment nor a decrement of the current time counts of 32768.
When the second digits read 00, 20, or 40, the settings of "1, 1, 1, 1, 1, 1, 0" in the F6, F5, F4, F3, F2, F1,
and F0 bits cause a decrement of the current time counts of 32768 by (- 2) x 2 to 32764 (a current time
count gain).
An increase of two clock pulses once per 20 seconds causes a time count loss of approximately 3 ppm (2 /
(32768 x 20 = 3.051 ppm). Conversely, a decrease of two clock pulses once per 20 seconds causes a time
count gain of 3 ppm. Consequently, deviations in time counts can be corrected with a precision of ±1.5
ppm. Note that the oscillation adjustment circuit is configured to correct deviations in time counts and not
the oscillation frequency of the 32.768-kHz clock pulses.
Adjustment Circuit".
*) Default settings: Default value means read / written values when the XSTP bit is set to “1” due to VDD
*
*
(Note that any mismatch between current time and preset alarm time specified by the Alarm_W registers
*
*
*
When the 12-hour mode is selected, the hour digits read 12 and 32 for 0 a.m. and 0 p.m., respectively.
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.
may disable the alarm interrupt circuit.)
(See "P12
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.
WM40
WM40
Indefinite
Indefinite
D6
D6
-
0
0
D6
WW6
WW6
WM20
WM20
Indefinite
WH20
WP⋅/A
WH20
WP⋅/A
Indefinite
Indefinite
D5
D5
D5
WW5
WW5
Control Register 1 (ADDRESS Eh) (2) /12⋅24: 12-/24-hour Mode Selection Bit")
power-on from 0v or oscillation stopping
WM10
WM10
Indefinite
Indefinite
Indefinite
D4
D4
WH10
WH10
D4
WW4
WW4
Indefinite
Indefinite
Indefinite
D3
WM8
WM8
D3
WH8
WH8
D3
WW3
WW3
Indefinite
Indefinite
Indefinite
D2
WM4
WM4
D2
WH4
WH4
D2
WW2
WW2
- 19 -
Indefinite
Indefinite
Indefinite
For further details, see "P.30
D1
WM2
WM2
D1
WH2
WH2
D1
WW1
WW1
Indefinite
Indefinite
Indefinite
D0
WM1
WM1
D0
WH1
WH1
D0
WW0
WW0
(For Writing)
(For Reading)
Default Settings *)
(For Writing)
(For Reading)
Default Settings *)
(For Writing)
(For Reading)
Default Settings *)
12345
Rx5C348A/B
Oscillation