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NUC126
Aug. 08, 2018
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521
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Rev 1.03
NUC12
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Hz clock output frequency based on compensated RTC clock source.
6.14.5.4 Time and Calendar Counter
RTC_TIME and RTC_CAL are used to load the real time and calendar. RTC_TALM and RTC_CALM
are used for setup alarm time and calendar.
6.14.5.5 12/24 hour Time Scale Selection
The 12/24 hour time scale selection depends on 24HEN (RTC_CLKFMT[0]).
When RTC runs as 12-hour time scale mode, RTC_TIME[21] (the high bit of TENHR[1:0]) means
AM/PM indication. In 12-hour time scale mode, PM hour digits in RTC_TIME[21:16] is PM hour time +
0x20, that is if current hour is PM01 and the PM hour digits should be 0x21 (0x01 + 0x20) . The
RTC_TIME[21:16] value in 12-hour and 24-hour time scale mode are all listed in Table 6.14-2.
Note: The Hour Value Write Into RTC_TIME[21:16] And Expressed In BCD Format.
24-Hour Time Scale
(24HEN = 1)
12-Hour Time Scale
(24HEN = 0)
0x00
0x12
0x12 (AM12)
0x32 (PM12)
0x01
0x13
0x01 (AM01)
0x21 (PM01)
0x02
0x14
0x02 (AM02)
0x22 (PM02)
0x03
0x15
0x03 (AM03)
0x23 (PM03)
0x04
0x16
0x04 (AM04)
0x24 (PM04)
0x05
0x17
0x05 (AM05)
0x25 (PM05)
0x06
0x18
0x06 (AM06)
0x26 (PM06)
0x07
0x19
0x07 (AM07)
0x27 (PM07)
0x08
0x20
0x08 (AM08)
0x28 (PM08)
0x09
0x21
0x09 (AM09)
0x29 (PM09)
0x10
0x22
0x10 (AM10)
0x30 (PM10)
0x11
0x23
0x11 (AM11)
0x31 (PM11)
Table 6.14-212/24-Hour Time Scale Selection
6.14.5.6 Day of the Week Counter
The RTC controller provides day of week in WEEKDAY (RTC_WEEKDAY[2:0]). The value is defined
from 0 to 6 to represent from Sunday to Saturday respectively.
6.14.5.7 Periodic Time Tick Interrupt
The RTC periodic time tick has 8 period interval options 1/128, 1/64, 1/32, 1/16, 1/8, 1/4, 1/2 and 1
second that are selected by TICK (RTC_TICK[2:0]). When specified time tick event generated, TICKIF
(RTC_INTSTS[1]) will be set to indicate time tick event occurred. If TICKIEN (RTC_INTEN[1]) is
enabled also, the time tick interrupt signal will be generated and inform to CPU periodically.
6.14.5.8 Alarm Interrupt
When the RTC real time and calendar in RTC_TIME and RTC_CAL registers are equal to alarm time
and calendar in RTC_TALM and RTC_CALM registers, the RTC alarm interrupt flag ALMIF