S-35390A-T8T1G 参数 Datasheet PDF下载

2-WIRE REAL-TIME CLOCK

S-35390A

Rev.2.4

_00

2.

Status register 1

Status register 1 is a 1-byte register that is used to display and set various modes. The bit configuration is shown below.

B7

RESET

W

B6

B5

SC0

R/W

B4

SC1

R/W

B3

INT1

R

R

:

W

:

R/W

:

B2

INT2

R

B1

BLD

R

B0

POC

R

12 / 24

R/W

Read

Write

Read/Write

Figure 12

B0 : POC

Status Register 1

This flag is used to confirm whether the power is on. The power-on detector operates at power-on and B0 is set to “1”.

This flag is Read-only. Once it is read, it is automatically set to “0”. When this flag is “1”, be sure to initialize. Regarding

the operation after power-on, refer to

“ Power-on Detection Circuit and Register Status”

.

B1 : BLD

This flag is set to “1” when the power supply voltage decreases to the level of detection voltage (V

DET

) or less. Users

can detect a drop in the power supply voltage. This flag is set to “1” once, is not set to “0” again even if the power

supply increases to the level of detection voltage (V

DET

) or more. This flag is Read-only. When this flag is “1”, be sure

to initialize. Regarding the operation of the power supply voltage detection circuit, refer to

“ Low Power Supply

Detection Circuit”

.

B2 : INT2, B3 : INT1

This flag indicates the time set by alarm and when the time has reached it. This flag is set to “1” when the time that

users set by using the alarm interrupt function has come. The INT1 flag in “1” at alarm 1 interrupt mode, the INT2 flag

in “1” at alarm 2 interrupt mode. This flag is Read-only. This flag is read once, is set to “0” automatically.

B4 : SC1, B5 : SC0

These flags are SRAM type registers, they are 2 bits as a whole, can be freely set by users.

B6 :

12 / 24

This flag is used to set 12-hour or 24-hour expression.

0 : 12-hour expression

1 : 24-hour expression

B7 : RESET

The internal IC is initialized by setting this bit to “1”. This bit is Write-only. It is always “0” when Read. When applying

the power supply voltage to the IC, be sure to write “1” to this bit to initialize the circuit. Regarding each status of data

after initialization, refer to

“ Register Status After Initialization

”.

12

Seiko Instruments Inc.