Datasheet

269
SAM4S [DATASHEET]
11100E–ATARM–24-Jul-13
The value obtained must be rounded to the nearest integer prior to being programmed into CORRECTION field.
If HIGHPPM = 1, then the clock frequency correction range is from 30.5 ppm up to 1950 ppm. The RTC accuracy is less
than 1 ppm for a range correction from 30.5 ppm up to 90 ppm.
The correction field must be programmed according to the required correction in ppm, the formula is as follows:
The value obtained must be rounded to the nearest integer prior to be programmed into CORRECTION field.
If NEGPPM is set to 1, the ppm correction is negative.
• OUT0: RTCOUT0 Output Source Selection
• OUT1: RTCOUT1 Output Source Selection
• THIGH: High Duration of the Output Pulse
Value Name Description
0 NO_WAVE no waveform, stuck at ‘0’
1 FREQ1HZ 1 Hz square wave
2 FREQ32HZ 32 Hz square wave
3 FREQ64HZ 64 Hz square wave
4 FREQ512HZ 512 Hz square wave
5 ALARM_TOGGLE output toggles when alarm flag rises
6 ALARM_FLAG output is a copy of the alarm flag
7 PROG_PULSE duty cycle programmable pulse
Value Name Description
0 NO_WAVE no waveform, stuck at ‘0’
1 FREQ1HZ 1 Hz square wave
2 FREQ32HZ 32 Hz square wave
3 FREQ64HZ 64 Hz square wave
4 FREQ512HZ 512 Hz square wave
5 ALARM_TOGGLE output toggles when alarm flag rises
6 ALARM_FLAG output is a copy of the alarm flag
7 PROG_PULSE duty cycle programmable pulse
Value Name Description
0 H_31MS 31.2 ms
1 H_16MS 15.6 ms
2 H_4MS 3.91 Oms
3 H_976US 976 μs
4 H_488US 488 μs
CORRECTION
3906
ppm
------------- 1–=