Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD 数据表

SAM4S Series [DATASHEET]

Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14

300

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).
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.
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.
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.
PIO lines associated to RTC outputs are automatically selecting these waveforms as soon as RTC_MR 

corresponding fields OUT0 and OUT1 differ from 0.

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

RTC_SCCR(ALRCLR)

alarm match
event 2

RTC_SCCR(ALRCLR)

toggle_alarm

pulse

Tperiod

Tperiod

Thigh