Datasheet

78K0/Kx2-L CHAPTER 10 REAL-TIME COUNTER
R01UH0028EJ0400 Rev.4.00 390
Sep 27, 2010
10.4.4 Setting alarm of real-time counter
Set time of alarm after setting 0 to WALE first.
Figure 10-23. Alarm Setting Procedure
WALE = 0
Setting ALARMWM
Start
INTRTC = 1?
Match operation of alarm is invalid.
Sets alarm minute register.
Alarm processing
Yes
WALIE = 1
Interrupt is generated when alarm matches.
Setting ALARMWH
Sets alarm hour register.
Setting ALARMWW
Sets alarm week register.
WALE = 1
Match operation of alarm is valid.
WAFG = 1?
No
Yes
Constant-period interrupt servicing
Match detection of alarm
No
Remarks 1. ALARMWM, ALARMWH, and ALARMWW may be written in any sequence.
2. Fixed-cycle interrupts and alarm match interrupts use the same interrupt source (INTRTC). When using
these two types of interrupts at the same time, which interrupt occurred can be judged by checking the
fixed-cycle interrupt status flag (RIFG) and the alarm detection status flag (WAFG) upon INTRTC
occurrence.