RX − 8564 LC

3) AIE bit ( Alarm Interrupt Enable )

This bit is used to control interrupt signal output from the /INT pin when an alarm interrupt event has occurred.

Writing "1" to this bit causes a low-level interrupt signal to be output from the /INT pin when an interrupt event occurs.

When a "0" is written to this bit, output from the /INT pin is prohibited (disabled).

AIE

Data

 

Description

 

 

1 ) When an alarm interrupt event occurs, an interrupt signal is not generated

 

0

or is canceled (/INT status remains Hi-z).

 

2 ) When an alarm interrupt event occurs, the interrupt signal is canceled

 

 

 

 

(/INT status changes from low to Hi-z).

Write / Read

 

 

 

 

When an alarm interrupt event occurs, an interrupt signal is generated (/INT

 

 

 

 

status changes from Hi-z to low).

 

1

∗

If the AIE bit value is changed from "0" to "1" without first canceling an

 

 

 

 

 

interrupt event (i.e., if the AF bit value remains "1"), the /INT pin is

 

 

 

immediately set to low level ("L").

 

 

 

 

∗To detect when an alarm interrupt event has occurred without having to set the /INT pin to low level, monitor the AF bit value (to see if it changes from "0" to "1") while keeping the AIE bit value as "0".

13.3.3.Examples of alarm settings

1)Basic information about alarm settings

•Four parameters can be set as alarm objects: minute, hour, day, and date.

•Hour settings are based on a 24-hour clock.

•To exclude a setting from possibly triggering an alarm interrupt, write "1" to the AE bit in the register corresponding to the setting in question.

∗If all four AE bits have a value of "1", no alarm interrupt events will occur.

•Alarm interrupt events occur when conditions change to become conditions which trigger an alarm.

2)Examples of alarm settings are listed below.

 

Reg − 0C[h]

Reg − 0B[h]

Reg − 0A[h]

Reg − 09[h]

 

Weekday

Day

Hour

Minute

 

Alarm

Alarm

Alarm

Alarm

 

[Weekday] set

[Day] set

[Hour] set

[Minute] set

 

 

 

 

 

At 7:30 AM every

01 h

AE bit "1"

07h

30h

(Monday

Monday

([Day] ignored)

(7:00 AM)

(30 [Minute])

[Weekday])

 

 

 

 

At 7:30 PM on the 15th

AE bit "1"

15 h

19 h

30 h

([Weekday]

of each month

([15] days)

(7:00 PM)

(30 minutes)

ignored)

 

 

 

 

At the top of each

AE bit "1"

AE bit "1"

AE bit "1"

00 h

([Weekday]

=hour (one-hour cycle)

([Day] ignored)

([Hour] ignored)

(00 minutes)

ignored)

 

 

 

 

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ETM12E-01