FOR AUTOMOTIVE 105°C OPERATION 2-WIRE REAL-TIME CLOCK

S-35390A H Series

Seiko Instruments Inc.

14

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

INT1FE

INT1ME

R / W

R / W

32kE

B6

B5

B4

B3

B2

B1

B0

INT2ME

INT2FE

INT1AE

R / W

R / W

R / W

R / W

R / W

R / W

INT2AE

TEST

R / W: Read / write

Figure 12 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, B2 : INT2ME, B3 : INT2FE

These bits are used to select the output mode for the

2

INT

pin. Table 11 shows how to select the mode. To use an

alarm 2 interrupt, set alarm interrupt mode, then access the INT2 register.

Table 11 Output Modes for

2

INT

Pin

INT2AE

INT2ME

INT2FE

2

INT

Pin Output Mode

0

0

0

No interrupt

−

*1

0

1

Output of user-set frequency

−

*1

1

0

Per-minute edge interrupt

−

*1

1

1

Minute-periodical interrupt 1 (50% duty)

1

0

0

Alarm 2 interrupt

*1.

Don't care (both of 0 and 1 are acceptable).

B4: 32kE, B5: INT1AE, B6: INT1ME, B7: INT1FE

These bits are used to select the output mode for the

1

INT

pin. Table 12 shows how to select the mode. To use

alarm 1 interrupt, access the INT1 register after setting the alarm interrupt mode.

Table 12 Output Modes for

1

INT

Pin

32kE

INT1AE

INT1ME

INT1FE

1

INT

Pin Output Mode

0

0

0

0

No interrupt

0

−

*1

0

1

Output of user-set frequency

0

−

*1

1

0

Per-minute edge interrupt

0

0

1

1

Minute-periodical interrupt 1 (50% duty)

0

1

0

0

Alarm 1 interrupt

0

1

1

1

Minute-periodical interrupt 2

1

−

*1

−

*1

−

*1

32.768 kHz output

*1.

Don't care (both of 0 and 1 are acceptable).