ATXMEGA256A3-MU Atmel, ATXMEGA256A3-MU Datasheet - Page 23

• Manufacturer Part Number: ATXMEGA256A3-MU
• Description: 8-bit Microcontrollers - MCU 8/16 bit 1.6V-3.6V 256KB + 8KB
• Manufacturer: Atmel

Specifications of ATXMEGA256A3-MU

• Product Category: 8-bit Microcontrollers - MCU
• Rohs: yes
• Core: AVR
• Data Bus Width: 8 bit/16 bit
• Maximum Clock Frequency: 32 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 16 KB
• On-chip Adc: Yes
• Package / Case: QFN EP
• Mounting Style: SMD/SMT
• A/d Bit Size: 12 bit
• A/d Channels Available: 8
• Data Rom Size: 4 KB
• Interface Type: I2C, SPI, USART
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Number Of Programmable I/os: 50
• Number Of Timers: 7
• Processor Series: ATXMega
• Program Memory Type: Flash
• Factory Pack Quantity: 260
• Supply Voltage - Max: 3.6 V
• Supply Voltage - Min: 1.6 V

12. System Control and Reset
12.1
12.2
12.3
12.3.1
12.3.2
12.3.3
12.3.4
12.3.5
8068T–AVR–12/10
Features
Resetting the AVR
Reset Sources
Power-On Reset
External Reset
Watchdog Reset
Brown-Out Reset
PDI reset
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•
•
During reset, all I/O registers are set to their initial values. The SRAM content is not reset. Appli-
cation execution starts from the Reset Vector. The instruction placed at the Reset Vector should
be an Absolute Jump (JMP) instruction to the reset handling routine. By default the Reset Vector
address is the lowest Flash program memory address, ‘0’, but it is possible to move the Reset
Vector to the first address in the Boot Section.
The I/O ports of the AVR are immediately tri-stated when a reset source goes active. The reset
functionality is asynchronous, so no running clock is required to reset the device. After the
device is reset, the reset source can be determined by the application by reading the Reset Sta-
tus Register.
The MCU is reset when the supply voltage VCC is below the Power-on Reset threshold voltage.
The MCU is reset when a low level is present on the RESET pin.
The MCU is reset when the Watchdog Timer period expires and the Watchdog Reset is enabled.
The Watchdog Timer runs from a dedicated oscillator independent of the System Clock. For
more details see
The MCU is reset when the supply voltage VCC is below the Brown-Out Reset threshold voltage
and the Brown-out Detector is enabled. The Brown-out threshold voltage is programmable.
The MCU can be reset through the Program and Debug Interface (PDI).
Multiple reset sources for safe operation and device reset
Asynchronous reset
Reset status register
– Power-On Reset
– External Reset
– Watchdog Reset
– Brown-Out Reset
– PDI reset
– Software reset
– No running clock in the device is required for reset
The Watchdog Timer runs from separate, dedicated oscillator
Accurate, programmable Brown-Out levels
”WDT - Watchdog Timer” on page
24.
XMEGA A3
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