Analog Devices SHARC ADSP-214 Series Hardware Reference Manual page 693

24 HOURS
EVENT
DAYS
COUNTER
9
Y Y
EQUAL?
9
ALARM
EVENT
DAY ALARM
EVENT
Figure 18-1. RTC Block Diagram
Digital Watch
The ADSP-2147x RTC provides a set of digital watch features. The inter-
nal oscillator generates a 32768 Hz signal using the crystal which is scaled
down to 1Hz and used to clock the second, minute, hour and day coun-
ters. The 32768-day counter is incremented each day at midnight (during
change from 23:59:59). The counter operates on the RTC supply (either
ADSP-214xx SHARC Processor Hardware Reference
www.BDTIC.com/ADI
HOURS
EVENT
HOURS MINUTES
COUNTER COUNTER
6
5
Y
EQUAL? EQUAL?
5 6
RTC_ALARM REGISTER
STOPWATCH
COUNTER
16
NORMAL
Y
COUNTDOWN
EQUAL 0?
Real-Time Clock—ADSP-2147x
MINUTES SECONDS
EVENT EVENT
1 Hz
TICK
SECONDS
COUNTER
6
Y
EQUAL?
6
STOPWATCH
EVENT
RTXI
32.768 kHz
WRITE
RTC_SWCNT
SET
RST
18-5