S-35199A01 Datasheet, PDF (16/54 Pages) Seiko Instruments Inc – 3-WIRE REAL-TIME CLOCK

3-WIRE REAL-TIME CLOCK
S-35199A01
Rev.1.0_00
3. Status Register 2
Status register 2 is a 1-byte register that is used to display and set various modes. The bit configuration is shown below.
B7
B6
B5
B4
B3
B2
B1
B0
INT1FE INT1ME INT1AE 32kE
SC2
SC3 INT2AE TEST
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W: Read/Write
Figure 16 Status Register 2
B0 : TEST
This is a test flag for SII. Be sure to set this flag to “0” in use. If this flag is set to “1”, be sure to initialize to set “0”.
B1 : INT2AE
This is an enable bit for alarm 2 interrupt. When this bit is “0”, alarm 2 interrupt is disabled. When it is “1”, it is enabled.
To use alarm 2 interrupt, access the INT register 2 and the alarm expansion register 2 after enabling this flag.
Caution Note that alarm 2 interrupt is output from the INT pin regardless of the settings in flags B4 to B7.
B2, B3 : SC3, SC2
These are 2-bit SRAM type registers that can be freely set by users.
B4 : 32kE, B5 : INT1AE, B6 : INT1ME, B7 : INT1FE
These bits are used to select the output mode for the INT pin. Table 10 shows how to select the mode. To use alarm
1 interrupt, access the INT register 1 and the alarm expansion register 1, after setting the alarm 1 interrupt mode.
Table 10 Output Modes for INT Pin
32kE
INT1AE
INT1ME
INT1FE
0
0
0
0
0
−^*1
0
1
0
−^*1
1
0
0
0
1
1
0
1
0
0
0
1
1
1
1
−^*1
−^*1
−^*1
*1. Don’t care (Both of 0 and 1 are acceptable).
INT Pin Output Mode
No interrupt
Output of user-set frequency
Per-minute edge interrupt
Minute-periodical interrupt 1 (50% duty)
Alarm 1 interrupt
Minute-periodical interrupt 2
32.768 kHz output
16
Seiko Instruments Inc.