Datasheet
Table Of Contents
- Features
- 1. Ordering Information
- 2. Pinout/Block Diagram
- 3. Overview
- 4. Resources
- 5. Capacitive touch sensing
- 6. AVR CPU
- 7. Memories
- 8. Event System
- 9. System Clock and Clock options
- 9.1 Features
- 9.2 Overview
- 9.3 Clock Sources
- 9.3.1 32kHz Ultra Low Power Internal Oscillator
- 9.3.2 32.768kHz Calibrated Internal Oscillator
- 9.3.3 32.768kHz Crystal Oscillator
- 9.3.4 0.4 - 16MHz Crystal Oscillator
- 9.3.5 2MHz Run-time Calibrated Internal Oscillator
- 9.3.6 32MHz Run-time Calibrated Internal Oscillator
- 9.3.7 External Clock Sources
- 9.3.8 PLL with 1x-31x Multiplication Factor
- 10. Power Management and Sleep Modes
- 11. System Control and Reset
- 12. WDT – Watchdog Timer
- 13. Interrupts and Programmable Multilevel Interrupt Controller
- 14. I/O Ports
- 15. TC0/1 – 16-bit Timer/Counter Type 0 and 1
- 16. TC2 – Timer/Counter Type 2
- 17. AWeX – Advanced Waveform Extension
- 18. Hi-Res – High Resolution Extension
- 19. RTC – 16-bit Real-Time Counter
- 20. USB – Universal Serial Bus Interface
- 21. TWI – Two-Wire Interface
- 22. SPI – Serial Peripheral Interface
- 23. USART
- 24. IRCOM – IR Communication Module
- 25. CRC – Cyclic Redundancy Check Generator
- 26. ADC – 12-bit Analog to Digital Converter
- 27. AC – Analog Comparator
- 28. Programming and Debugging
- 29. Pinout and Pin Functions
- 30. Peripheral Module Address Map
- 31. Instruction Set Summary
- 32. Packaging information
- 33. Electrical Characteristics TBD
- 34. Typical Characteristics TBD
- 35. Errata
- 36. Datasheet Revision History
- Table of Contents
11
8493A–AVR–02/12
XMEGA C4
7. Memories
7.1 Features
• Flash program memory
– One linear address space
– In-system programmable
– Self-programming and boot loader support
– Application section for application code
– Application table section for application code or data storage
– Boot section for application code or boot loader code
– Separate read/write protection lock bits 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
4 bit-accessible general purpose registers for global variables or flags
– Separate buses for SRAM, EEPROM and I/O memory
Simultaneous bus access for CPU
• Production signature row memory for factory programmed data
– ID for each microcontroller device type
– Serial number for each device
– Calibration bytes for factory calibrated peripherals
• User signature row
– One flash page in size
– Can be read and written from software
– Content is kept after chip erase
7.2 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.
The available memory size configurations are shown in ”Ordering Information” on page 2. In
addition, each device has a Flash memory signature row for calibration data, device identifica-
tion, serial number etc.