ATTINY861A-SU Atmel, ATTINY861A-SU Datasheet - Page 15

• Manufacturer Part Number: ATTINY861A-SU
• Description: IC, MCU, 8BIT, 8K FLASH, 20SOIC
• Manufacturer: Atmel

Specifications of ATTINY861A-SU

• Controller Family/series: ATtiny
• No. Of I/o's: 16
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 512Byte
• Cpu Speed: 20MHz
• No.: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 8KB
• Oscillator Type: External, Internal
• Rohs Compliant: Yes

5. Memories
5.1
5.2
8197B–AVR–01/10
In-System Re-programmable Flash Program Memory
SRAM Data Memory
This section describes the different memories of the ATtiny261A/461A/861A. The AVR architec-
ture has two main memory spaces, the Data memory and the Program memory space. In
addition, the ATtiny261A/461A/861A features an EEPROM Memory for data storage. All three
memory spaces are linear and regular.
The ATtiny261A/461A/861A contains 2/4/8K byte 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 1024/2048/4096 x 16.
The Flash memory has an endurance of at least 10,000 write/erase cycles. The
ATtiny261A/461A/861A Program Counter (PC) is 10/11/12 bits wide, thus capable of addressing
the 1024/2048/4096 Program memory locations.
a detailed description on Flash data serial downloading using the SPI pins.
Constant tables can be allocated within the entire address space of program memory (see the
LPM – Load Program memory instruction description).
Timing diagrams for instruction fetch and execution are presented in
ing” on page
Figure 5-1.
Figure 5-2 on page 16
The lower data memory locations address both the Register File, the I/O memory and the inter-
nal data SRAM. The first 32 locations address the Register File, the next 64 locations the
standard I/O memory, and the last 128/256/512 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.
12.
Program Memory Map
shows how the ATtiny261A/461A/861A SRAM Memory is organized.
Program Memory
0x03FF/0x07FF/0x0FFF
0x0000
“Memory Programming” on page 167
“Instruction Execution Tim-
contains
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