Datasheet

 2018 Microchip Technology Inc. Data Sheet Complete DS40002072A-page 3
ATmega32A
Table of Contents
1 Pin Configurations ................................................................................. 10
2 Overview ................................................................................................. 11
2.1 Block Diagram ................................................................................................. 11
2.2 Pin Descriptions............................................................................................... 12
3 Resources ............................................................................................... 13
4 Data Retention ........................................................................................ 13
5 About Code Examples ........................................................................... 14
6 Capacitive touch sensing ...................................................................... 14
7 AVR CPU Core ........................................................................................ 15
7.1 Overview.......................................................................................................... 15
7.2 ALU – Arithmetic Logic Unit............................................................................. 16
7.3 Status Register ................................................................................................ 16
7.4 General Purpose Register File ........................................................................ 17
7.5 Stack Pointer ................................................................................................... 19
7.6 Instruction Execution Timing ........................................................................... 20
7.7 Reset and Interrupt Handling........................................................................... 21
8 AVR Memories ........................................................................................ 23
8.1 Overview.......................................................................................................... 23
8.2 In-System Reprogrammable Flash Program Memory ..................................... 23
8.3 SRAM Data Memory........................................................................................ 24
8.4 EEPROM Data Memory .................................................................................. 25
8.5 I/O Memory...................................................................................................... 26
8.6 Register Description ........................................................................................ 27
9 System Clock and Clock Options ......................................................... 31
9.1 Clock Systems and their Distribution............................................................... 31
9.2 Clock Sources ................................................................................................. 32
9.3 Default Clock Source....................................................................................... 32
9.4 Crystal Oscillator ............................................................................................. 32
9.5 Low-frequency Crystal Oscillator..................................................................... 34
9.6 External RC Oscillator ..................................................................................... 34
9.7 Calibrated Internal RC Oscillator ..................................................................... 35
9.8 External Clock ................................................................................................. 36