Atmel ATtiny26

i
ATtiny26(L)
1477G–AVR–03/05
Table of Contents Features................................................................................................ 1
Pin Configuration................................................................................. 2
Description........................................................................................... 3
Block Diagram ...................................................................................................... 4
Pin Descriptions.................................................................................................... 5
About Code Examples......................................................................... 5
AVR CPU Core ..................................................................................... 6
Architectural Overview.......................................................................................... 6
General Purpose Register File ............................................................................. 7
ALU – Arithmetic Logic Unit.................................................................................. 8
Status Register – SREG....................................................................................... 9
Stack Pointer – SP.............................................................................................. 10
Program and Data Addressing Modes................................................................ 10
Memories............................................................................................ 15
In-System Programmable Flash Program Memory ............................................ 16
SRAM Data Memory........................................................................................... 16
EEPROM Data Memory...................................................................................... 17
I/O Memory......................................................................................................... 20
System Clock and Clock Options .................................................... 22
Clock Systems and their Distribution.................................................................. 22
Clock Sources..................................................................................................... 24
Default Clock Source.......................................................................................... 25
Crystal Oscillator................................................................................................. 25
Low-frequency Crystal Oscillator........................................................................ 26
External RC Oscillator ........................................................................................ 27
Calibrated Internal RC Oscillator ........................................................................ 28
External Clock..................................................................................................... 29
High Frequency PLL Clock – PLLCLK................................................................ 30
System Control and Reset................................................................ 31
Power-on Reset.................................................................................................. 32
External Reset .................................................................................................... 33
Brown-out Detection ........................................................................................... 34
Watchdog Reset ................................................................................................. 34
MCU Status Register – MCUSR......................................................................... 35
Power Management and Sleep Modes............................................. 36
MCU Control Register – MCUCR ....................................................................... 36
Idle Mode............................................................................................................ 37
ADC Noise Reduction Mode............................................................................... 37