ATMEGA64-16AI datasheet(18/393 Pages) ATMEL

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ATmega64(L)

2490L–AVR–10/06

AVR Memories

This section describes the different memories in the ATmega64. The AVR architecture

has two main memory spaces, the Data Memory and the Program Memory space. In

addition, the ATmega64 features an EEPROM Memory for data storage. All three mem-

ory spaces are linear and regular.

In-System

Reprogrammable Flash

Program Memory

The ATmega64 contains 64K bytes On-chip In-System Reprogrammable Flash memory

for program storage. Since all AVR instructions are 16 or 32 bits wide, the Flash is orga-

nized as 32K x 16. For software security, the Flash Program memory space is divided

into two sections, Boot Program section and Application Program section.

The Flash memory has an endurance of at least 10,000 write/erase cycles. The

ATmega64 Program Counter (PC) is 15 bits wide, thus addressing the 32K program

memory locations. The operation of Boot Program section and associated Boot Lock

bits for software protection are described in detail in “Boot Loader Support – Read-

While-Write Self-programming” on page 278. “Memory Programming” on page 291 con-

tains a detailed description on Flash programming in SPI, JTAG, or Parallel

Programming mode.

Constant tables can be allocated within the entire program memory address space (see

the LPM – Load Program Memory instruction description).

Timing diagrams for instruction fetch and execution are presented in “Instruction Execu-

tion Timing” on page 15.

Figure 8. Program Memory Map

$0000

$7FFF

Application Flash Section

Boot Flash Section

ATMEGA64-16AI Datasheet(PDF) 18 Page - ATMEL Corporation