Datasheet

221
11011B–ATARM–21-Feb-12
SAM3N
221
11011B–ATARM–21-Feb-12
SAM3N
13. Real-time Timer (RTT)
13.1 Description
The Real-time Timer is built around a 32-bit counter used to count roll-over events of the
programmable16-bit prescaler which enables counting elapsed seconds from a 32 kHz slow
clock source. It generates a periodic interrupt and/or triggers an alarm on a programmed value.
13.2 Embedded Characteristics
• 32-bit Free-running Counter on prescaled slow clock
• 16-bit Configurable Prescaler
• Interrupt on Alarm
13.3 Block Diagram
Figure 13-1. Real-time Timer
SLCK
RTPRES
RTTINC
ALMS
16-bit
Divider
32-bit
Counter
ALMV
=
CRTV
RTT_MR
RTT_VR
RTT_AR
RTT_SR
RTTINCIEN
RTT_MR
0
10
ALMIEN
rtt_int
RTT_MR
set
set
RTT_SR
read
RTT_SR
reset
reset
RTT_MR
reload
rtt_alarm
RTTRST
RTT_MR
RTTRST