S-35390A Datasheet, PDF (21/54 Pages) Seiko Instruments Inc – 2-WIRE REAL-TIME CLOCK

Rev.2.4_00
2-WIRE REAL-TIME CLOCK
S-35390A
„ INT1 Pin and INT2 Pin Output Mode
These are selectable for the output mode for INT1 and INT2 pins;
Alarm interrupt, the output of user-set frequency, per-minute edge interrupt output, minute-periodical interrupt output 1. In
the INT1 pin output mode, in addition to the above modes, minute-periodical interrupt output 2 and 32.768 kHz output are
also selectable.
To switch the output mode, use the status register 2. Refer to “3. Status register 2” in “„ Configuration of Register”.
When switching the output mode, be careful of the output status of the pin. Especially, when using alarm interrupt/output of
frequency, switch the output mode after setting “00h” in the INT1/INT2 register. In 32.768 kHz output/per-minute edge
interrupt output/minute-periodical interrupt output, it is unnecessary to set data in the INT1/INT2 register for users.
Refer to the followings regarding each operation of output modes.
1. Alarm interrupt output
Alarm interrupt output is the function to output “L” from the INT1/ INT2 pin, at the alarm time which is set by user has
come. If setting the pin output to “H”, turn off the alarm function by setting “0” in INT1AE/INT2AE in the status register 2.
To set the alarm time, set the data of day of the week, hour and minute in the INT1/INT2 register. Refer to “4. INT1
register and INT2 register” in “„ Configuration of Register”.
Alarm setting of W (day of the week), H (hour), m (minute)”
Status register 2 setting
• INT1 pin output mode
32kE = 0, INT1ME = INT1FE = 0
• INT2 pin output mode
INT2ME = INT2FE = 0
INT1 register
INT2 register
INTx register alarm enable flag
• AxHE = AxmE = AxWE = "1"
mx Hx Wx
Comparator
Alarm interrupt
Real-time data
Second Minute
Hour
Day of
the week
Day
Month
Year
Real-time data
W (day of the week)
H h (m − 1) m 59 s
H h 00 m 00 s 01 s
59 s _{H h (m + 1) m 00 s}
Change by program
Change by program Change by program
INT1AE/INT2AE
*1
Alarm time matches
INT1 pin/INT2 pin
OFF
Period when alarm time matches
*1. If users clear INT1AE/INT2AE once; “L” is not output from the INT1/ INT2 pin by setting INT1AE/INT2AE enable again,
within a period when the alarm time matches real-time data.
Figure 24 Alarm Interrupt Output Timing (1/2)
Seiko Instruments Inc.
21