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8126F–AVR–05/12
ATtiny13A
5.
Memories
This section describes the different memories in the ATtiny13A. The AVR architecture has two
main memory spaces, the Data memory and the Program memory space. In addition, the
ATtiny13A features an EEPROM Memory for data storage. All three memory spaces are linear
and regular.
5.1
In-System Reprogrammable Flash Program Memory
The ATtiny13A contains 1K byte On-chip In-System Reprogrammable Flash memory for pro-
gram storage. Since all AVR instructions are 16 or 32 bits wide, the Flash is organized as 512 x
16.
The Flash memory has an endurance of at least 10,000 write/erase cycles. The ATtiny13A Pro-
gram Counter (PC) is nine bits wide, thus addressing the 512 Program memory locations.
“Memory Programming” on page 103
contains a detailed description on Flash data serial down-
loading using the SPI pins.
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
Figure 5-1.
Program Memory Map
5.2
SRAM Data Memory
shows how the ATtiny13A SRAM Memory is organized.
The lower 160 Data memory locations address both the Register File, the I/O memory and the
internal data SRAM. The first 32 locations address the Register File, the next 64 locations the
standard I/O memory, and the last 64 locations address the internal data SRAM.
The five different addressing modes for the Data memory cover: Direct, Indirect with Displace-
ment, Indirect, Indirect with Pre-decrement, and Indirect with Post-increment. In the Register
File, registers R26 to R31 feature the indirect addressing pointer registers.
The direct addressing reaches the entire data space.
The Indirect with Displacement mode reaches 63 address locations from the base address given
by the Y- or Z-register.
0x0000
0x01FF
Program Memory