ATMEGA48 Datasheet, PDF (369/377 Pages) ATMEL Corporation – 8-bit Microcontroller with 8K Bytes In-System Programmable Flash

ATmega48/88/168
Table of contents
Features ..................................................................................................... 1
1 Pin configurations ................................................................................... 2
1.1Pin descriptions .........................................................................................................3
2 Overview ................................................................................................... 5
2.1Block diagram ............................................................................................................5
2.2Comparison between Atmel ATmega48, Atmel ATmega88, and Atmel ATmega168 .
6
3 Resources ................................................................................................. 8
4 Data retention ........................................................................................... 8
5 About code examples .............................................................................. 8
6 Capacitive touch sensing ........................................................................ 8
7 AVR CPU core .......................................................................................... 9
7.1Overview ...................................................................................................................9
7.2Architectural overview ...............................................................................................9
7.3ALU – Arithmetic Logic Unit ....................................................................................10
7.4Status register .........................................................................................................11
7.5General purpose register file ...................................................................................12
7.6Stack pointer ...........................................................................................................13
7.7Instruction execution timing .....................................................................................14
7.8Reset and interrupt handling ...................................................................................15
8 AVR memories ....................................................................................... 17
8.1Overview .................................................................................................................17
8.2In-system reprogrammable flash program memory .................................................17
8.3SRAM data memory ................................................................................................19
8.4EEPROM data memory ...........................................................................................20
8.5I/O memory ..............................................................................................................21
8.6Register description .................................................................................................22
9 System clock and clock options .......................................................... 27
9.1Clock systems and their distribution ........................................................................27
9.2Clock sources ..........................................................................................................28
9.3Low power crystal oscillator ....................................................................................29
9.4Full swing crystal oscillator ......................................................................................31
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2545T–AVR–05/11