ATMEGA325-16AJ ATMEL [ATMEL Corporation], ATMEGA325-16AJ Datasheet - Page 341

• Manufacturer Part Number: ATMEGA325-16AJ
• Description: 8-bit Microcontroller with In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Table of Contents
2570A–AVR–09/04
Features................................................................................................ 1
Features (Continued)........................................................................... 2
Pin Configurations............................................................................... 2
Overview............................................................................................... 4
About Code Examples......................................................................... 8
AVR CPU Core ..................................................................................... 9
AVR ATmega325/3250/645/6450 Memories ..................................... 17
System Clock and Clock Options .................................................... 25
Power Management and Sleep Modes............................................. 33
Disclaimer ............................................................................................................. 3
Block Diagram ...................................................................................................... 4
Comparison between ATmega325, ATmega3250, ATmega645 and ATmega6450
6
Pin Descriptions.................................................................................................... 6
Introduction ........................................................................................................... 9
Architectural Overview.......................................................................................... 9
ALU – Arithmetic Logic Unit................................................................................ 10
Status Register ................................................................................................... 11
General Purpose Register File ........................................................................... 12
Stack Pointer ...................................................................................................... 13
Instruction Execution Timing............................................................................... 14
Reset and Interrupt Handling.............................................................................. 14
In-System Reprogrammable Flash Program Memory ........................................ 17
SRAM Data Memory........................................................................................... 18
EEPROM Data Memory...................................................................................... 19
I/O Memory ......................................................................................................... 24
Clock Systems and their Distribution .................................................................. 25
Clock Sources..................................................................................................... 26
Default Clock Source .......................................................................................... 26
Crystal Oscillator................................................................................................. 26
Low-frequency Crystal Oscillator ........................................................................ 28
Calibrated Internal RC Oscillator ........................................................................ 28
External Clock..................................................................................................... 29
Clock Output Buffer ............................................................................................ 30
Timer/Counter Oscillator..................................................................................... 30
System Clock Prescaler...................................................................................... 31
Idle Mode ............................................................................................................ 34
ADC Noise Reduction Mode............................................................................... 34
ATmega325/3250/645/6450
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