ATAVRONEKIT Atmel, ATAVRONEKIT Datasheet - Page 24

• Manufacturer Part Number: ATAVRONEKIT
• Description: KIT AVR/AVR32 DEBUGGER/PROGRMMR
• Manufacturer: Atmel
• Series: AVR®r
• Type: Debuggerr

Specifications of ATAVRONEKIT

• Contents: Programmer/Debugger
• Processor To Be Evaluated: AVR32
• Data Bus Width: 32 bit
• Interface Type: ISP, JTAG
• Core Architecture: AVR
• Kit Contents: ATAVRONEKIT
• Tool / Board Applications: General Purpose MCU, MPU, DSP, DSC
• Development Tool Type: Hardware / Software - Dev Kit (Dev Tool)
• Rohs Compliant: Yes
• Mcu Supported Families: AVR32 32-bit MCU
• For Use With/related Products: AVR® Devices
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

12.3.6
12.4
12.4.1
12.4.2
8067M–AVR–09/10
WDT - Watchdog Timer
Software reset
Features
Overview
The MCU can be reset by the CPU writing to a special I/O register through a timed sequence.
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The XMEGA A1 has a Watchdog Timer (WDT). The WDT will run continuously when turned on
and if the Watchdog Timer is not reset within a software configurable time-out period, the micro-
controller will be reset. The Watchdog Reset (WDR) instruction must be run by software to reset
the WDT, and prevent microcontroller reset.
The WDT has a Window mode. In this mode the WDR instruction must be run within a specified
period called a window. Application software can set the minimum and maximum limits for this
window. If the WDR instruction is not executed inside the window limits, the microcontroller will
be reset.
A protection mechanism using a timed write sequence is implemented in order to prevent
unwanted enabling, disabling or change of WDT settings.
For maximum safety, the WDT also has an Always-on mode. This mode is enabled by program-
ming a fuse. In Always-on mode, application software can not disable the WDT.
11 selectable timeout periods, from 8 ms to 8s.
Two operation modes
Runs from the 1 kHz output of the 32 kHz Ultra Low Power oscillator
Configuration lock to prevent unwanted changes
– Standard mode
– Window mode
XMEGA A1
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