Datasheet

18
8021G–AVR–03/11
ATmega329P/3290P
7. AVR Memories
7.1 Overview
This section describes the different memories in the ATmega329P/3290P. The Atmel
®
AVR
®
architecture has two main memory spaces, the Data Memory and the Program Memory space.
In addition, the ATmega329P/3290P features an EEPROM Memory for data storage. All three
memory spaces are linear.
7.2 In-System Reprogrammable Flash Program Memory
The ATmega329P/3290P contains 132Kbytes 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 16K x 16 (ATmega329P/3290P). 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
ATmega329P/3290P Program Counter (PC) is 14 bits wide, thus addressing the 16K 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-Pro-
gramming” on page 281. ”Memory Programming” on page 296 contains a detailed description
on Flash data serial downloading using the SPI pins or the JTAG interface.
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 Execution Tim-
ing” on page 15.
Figure 7-1. Program Memory Map
7.3 SRAM Data Memory
Figure 7-2 shows how the SRAM Memory is organized.
0x0000
0x3FFF
Program Memory
Application Flash Section
Boot Flash Section