Datasheet

12
[Not recommended for new designs - Use XMEGA A1U series] XMEGA A1 [DATASHEET]
8067O–AVR–06/2013
8. Memories
8.1 Features
 Flash Program Memory
 One linear address space
 In-System Programmable
 Self-Programming and Bootloader support
 Application Section for application code
 Application Table Section for application code or data storage
 Boot Section for application code or bootloader code
 Separate lock bits and protection for all sections
 Built in fast CRC check of a selectable flash program memory section
 Data Memory
 One linear address space
 Single cycle access from CPU
 SRAM
 EEPROM
 Byte and page accessible
 Optional memory mapping for direct load and store
 I/O Memory
 Configuration and Status registers for all peripherals and modules
 16 bit-accessible General Purpose Register for global variables or flags
 External Memory support
 SRAM
 SDRAM
 Memory mapped external hardware
 Bus arbitration
 Safe and deterministic handling of CPU and DMA Controller priority
 Separate buses for SRAM, EEPROM, I/O Memory and External Memory access
 Simultaneous bus access for CPU and DMA Controller
 Production Signature Row Memory for factory programmed data
 Device ID for each microcontroller device type
 Serial number for each device
 Oscillator calibration bytes
 ADC, DAC and temperature sensor calibration data
 User Signature Row
 One flash page in size
 Can be read and written from software
 Content is kept after chip erase
8.2 Overview
The Atmel AVR architecture has two main memory spaces, the program memory and the data memory. Executable code
can reside only in the program memory, while data can be stored in the program memory and the data memory. The data
memory includes the internal SRAM, and EEPROM for nonvolatile data storage. All memory spaces are linear and
require no memory bank switching. Nonvolatile memory (NVM) spaces can be locked for further write and read/write
operations. This prevents unrestricted access to the application software.
A separate memory section contains the fuse bytes. These are used for configuring important system functions, and can
only be written by an external programmer.