Atmel Xplained Pro Evaluation Kit for the ATSAMD21J18A Microcontroller ATSAMD21-XPRO ATSAMD21-XPRO Data Sheet
Product codes
ATSAMD21-XPRO
112
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181C–SAM-D21_Datasheet–07/2014
There are two groups of reset sources:
z
Power Reset: Resets caused by an electrical issue.
z
User Reset: Resets caused by the application.
The table below lists the parts of the device that are reset, depending on the reset type.
The external reset is generated when pulling the RESET pin low. This pin has an internal pull-up, and does not need to
be driven externally during normal operation.
be driven externally during normal operation.
The POR, BOD12 and BOD33 reset sources are generated by their corresponding module in the System Controller
Interface (SYSCTRL).
Interface (SYSCTRL).
The WDT reset is generated by the Watchdog Timer.
The System Reset Request (SysResetReq) is a software reset generated by the CPU when asserting the
SYSRESETREQ bit located in the Reset Control register of the CPU (See the ARM
SYSRESETREQ bit located in the Reset Control register of the CPU (See the ARM
®
Cortex
®
http://www.arm.com
).
Table 15-2. Effects of the Different Reset Events
Power Reset
User Reset
POR, BOD12, BOD33
External Reset
WDT Reset,
SysResetReq
RTC
All the 32kHz sources
WDT with ALWAYSON feature
Generic Clock with WRTLOCK
feature
All the 32kHz sources
WDT with ALWAYSON feature
Generic Clock with WRTLOCK
feature
Y
N
N
Debug logic
Y
Y
N
Others
Y
Y
Y