RV5C387A_03 Datasheet, PDF (16/49 Pages) RICOH electronics devices division – I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC WITH VOLTAGE MONITORING FUNCTION

RV5C387A
2.2-6 CTFG
Periodic Interrupt Flag Bit
CTFG
Description
0
Periodic interrupt output “H” (OFF)
(Default setting)
1
Periodic interrupt output “L” (ON)
The CTFG bit is set to 1 when the periodic interrupt signals are output from the INTRA pin (“L”). The CTFG bit
accepts only the writing of 0 in the level mode, which disables (“H”) the INTRA pin until it is enabled (“L”) again in
the next interrupt cycle. Conversely, setting the CTFG bit to 1 causes no event.
2.2-7 WAFG and DAFG
Alarm_W Flag Bit and Alarm_D Flag Bit
WAFG, DAFG
Description
0
Indicating a mismatch between current time and preset alarm time
(Default setting)
1
Indicating a match between current time and preset alarm time
The WAFG and DAFG bits are valid only when the WALE and DALE bits have the setting of 1, which is caused
approximately 61µs after any match between current time and preset alarm time specified by the Alarm_W registers
and the Alarm_D registers. The WAFG and DAFG bits accept only the writing of 0, which disables (“H”) the INTRB
or INTRC pin until it is enabled (“L”) again at the next preset alarm time. Conversely, setting the WAFG and DAFG
bits to 1 causes no event. The WAFG and DAFG bits will have the reading of 0 when the alarm interrupt circuit is
disabled with the WALE and DALE bits set to 0. The settings of the WAFG and DAFG bits are synchronized with
the output of the INTRB and INTRC pins as shown in the timing chart below.
Output Relationships Between the WAFG or DAFG Bit and INTRB, INTRC
Approx.61µs
Approx.61µs
Settings of WAFG (DAFG) bit
Output of INTRB (INTRC) pin
Writing of 0 to WAFG
(DAFG) bit
Writing of 0 to WAFG
(DAFG) bit
(Match between current time (Match between current time (Match between current time
and preset alarm time)
and preset alarm time)
and preset alarm time)
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