Atmel Evaluation Kit for the SAM4E Series of Flash Microcontrollers ATSAM4E-EK ATSAM4E-EK Data Sheet
Product codes
ATSAM4E-EK
SAM4E [DATASHEET]
Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14
336
The first selection choice sticks the associated output at 0 (This is the reset value and it can be used at any time to
disable the waveform generation).
disable the waveform generation).
Selection choices 1 to 4 respectively select 1 Hz, 32 Hz, 64 Hz and 512 Hz.
32 Hz or 64 Hz can drive, for example, a TN LCD backplane signal while 1 Hz can be used to drive a blinking
character like “:” for basic time display (hour, minute) on TN LCDs.
character like “:” for basic time display (hour, minute) on TN LCDs.
Selection choice 5 provides a toggling signal when the RTC alarm is reached.
Selection choice 6 provides a copy of the alarm flag, so the associated output is set high (logical 1) when an alarm
occurs and immediately cleared when software clears the alarm interrupt source.
occurs and immediately cleared when software clears the alarm interrupt source.
Selection choice 7 provides a 1 Hz periodic high pulse of 15 µs duration that can be used to drive external devices
for power consumption reduction or any other purpose.
for power consumption reduction or any other purpose.
PIO lines associated to RTC outputs are automatically selecting these waveforms as soon as RTC_MR
corresponding fields OUT0 and OUT1 differ from 0.
corresponding fields OUT0 and OUT1 differ from 0.
Figure 16-3.
Waveform Generation
RTCOUT1
‘0’
1 Hz
32 Hz
64 Hz
512 Hz
toggle_alarm
flag_alarm
pulse
0
1
2
3
4
5
6
7
RTC_MR(OUT1)
RTCOUT0
‘0’
1 Hz
32 Hz
64 Hz
512 Hz
toggle_alarm
flag_alarm
pulse
0
1
2
3
4
5
6
7
RTC_MR(OUT0)
flag_alarm
alarm match
event 1
event 1
RTC_SCCR(ALRCLR)
alarm match
event 2
event 2
RTC_SCCR(ALRCLR)
toggle_alarm
pulse
Tperiod
Tperiod
Thigh