Section 13 Realtime Clock (RTC)
Rev. 5.00 May 29, 2006 page 359 of 698
REJ09B0146-0500
13.4.4
Alarm Function
Figure 13.4 shows how to use the alarm function.
Alarms can be generated using seconds, minutes, hours, day of the week, date, month, or any
combination of these. Set the ENB bit (bit 7) 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
placed to 0.
When the clock and alarm times match, 1 is set in the AF bit (bit 0) in RCR1. Alarm detection can
be checked by reading this bit, but normally it is done by interrupt. If 1 is placed in the AIE bit (bit
3) in RCR1, an interrupt is generated when an alarm occurs.
Disable interrupt to prevent errorneous
interruption (AIE bit in RCR1 is cleared).
Then write 1.
Clock running
Set alarm time
Set whether to use
alarm interrupt
Always reset, since the flag may have been
set while the alarm time was being set
(AF bit in RCR1 is cleared).
Clear alarm flag
Monitor alarm time
(wait for interrupt or
check alarm flag)
Figure 13.4 Using the Alarm Function
Содержание SH7706 Series
Страница 8: ...Rev 5 00 May 29 2006 page viii of xlviii ...
Страница 160: ...Section 5 Cache Rev 5 00 May 29 2006 page 112 of 698 REJ09B0146 0500 ...
Страница 370: ...Section 11 Watchdog Timer WDT Rev 5 00 May 29 2006 page 322 of 698 REJ09B0146 0500 ...
Страница 532: ...Section 16 Serial Communication Interface with FIFO SCIF Rev 5 00 May 29 2006 page 484 of 698 REJ09B0146 0500 ...
Страница 554: ...Section 17 Pin Function Controller PFC Rev 5 00 May 29 2006 page 506 of 698 REJ09B0146 0500 ...
Страница 576: ...Section 18 I O Ports Rev 5 00 May 29 2006 page 528 of 698 REJ09B0146 0500 ...
Страница 614: ...Section 21 User Debugging Interface H UDI Rev 5 00 May 29 2006 page 566 of 698 REJ09B0146 0500 ...
Страница 746: ...Index Rev 5 00 May 29 2006 page 698 of 698 REJ09B0146 0500 ...
Страница 749: ...SH7706 Group Hardware Manual ...