R5S72011 RENESAS [Renesas Technology Corp], R5S72011 Datasheet - Page 688

• Manufacturer Part Number: R5S72011
• Description: 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7200 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 15 Realtime Clock (RTC)
15.4.4
Figure 15.4 shows how to use the alarm function.
Alarms can be generated using seconds, minutes, hours, day of the week, date, month, year, or any
combination of these. Set the ENB bit in the register on which the alarm is placed to 1, and then
set the alarm time in the lower bits. Clear the ENB bit in the register on which the alarm is not
placed to 0.
When the clock and alarm times match, 1 is set in the AF bit in RCR1. Alarm detection can be
checked by reading this bit, but normally it is done by interrupt. If 1 is set in the AIE bit in RCR1,
an interrupt is generated when an alarm occurs.
The alarm flag is set when the clock and alarm times match. However, the alarm flag can be
cleared by writing 0.
Rev. 2.00 Sep. 07, 2007 Page 660 of 1164
REJ09B0321-0200
Alarm Function
Disable alarm interrupt
Enable alarm interrupt
(wait for interrupt or
Monitor alarm time
check alarm flag)
Clear alarm flag
Set alarm time
Clock running
Figure 15.4 Using Alarm Function
Write 0 to AIE in RCR1
to prevent errorneous interrupt
Always clear, since the flag may have been
set while the alarm time was being set.
Write 1 to AIE in RCR1