AT90PWM2 datasheet(20/365 Pages) ATMEL

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AT90PWM2/3

4317B–AVR–02/05

Memories

This section describes the different memories in the AT90PWM2/3. The AVR architec-

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

In addition, the AT90PWM2/3 features an EEPROM Memory for data storage. All three

memory spaces are linear and regular.

In-System

Reprogrammable Flash

Program Memory

The AT90PWM2/3 contains 8K bytes On-chip In-System Reprogrammable Flash mem-

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

organized as 4K 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

AT90PWM2/3 Program Counter (PC) is 12 bits wide, thus addressing the 4K 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 273. “Memory Programming” on page 287 con-

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

mode.

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

the LPM – Load Program Memory.

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

tion Timing” on page 16.

Figure 10. Program Memory Map

0x0000

0x0FFF

Program Memory

Application Flash Section

Boot Flash Section

AT90PWM2 Datasheet(PDF) 20 Page - ATMEL Corporation