Operands are contained in register r (Rr) and d (Rd). The result is stored in register d (Rd). I/O DirectFigure 7. I/O Direct Addressing Operand address is contained in 6 bits of the instruction word. “n” is the destination or source register address. Relative Program Addressing, Figure 8. Relative Program Memory Addressing RJMP and RCALL +1 Program execution continues at address PC + k + 1. The relative address k is -2048 to 2047. Constant Addressing usingFigure 9. Code Memory Constant Addressing the LPM Instruction $1FF 8ATtiny15L 1187H–AVR–09/07 Document Outline Features Pin Configuration Description Block Diagram Pin Descriptions VCC GND Port B (PB5..PB0) Analog Pins Internal Oscillators ATtiny15L Architectural Overview The General Purpose Register File The ALU - Arithmetic Logic Unit The Flash Program Memory The Program and Data Addressing Modes Register Direct, Single- register Rd Register Indirect Register Direct, Two Registers Rd and Rr I/O Direct Relative Program Addressing, RJMP and RCALL Constant Addressing using the LPM Instruction Subroutine and Interrupt Hardware Stack The EEPROM Data Memory Memory Access and Instruction Execution Timing I/O Memory The Status Register - SREG Reset and Interrupt Handling ATtiny15L Reset Sources Power-on Reset External Reset Brown-out Detection Watchdog Reset MCU Status Register - MCUSR Internal Voltage Reference Voltage Reference Enable Signals and Start-up Time Interrupt Handling Interrupt Response Time The General Interrupt Mask Register - GIMSK The General Interrupt Flag Register - GIFR The Timer/Counter Interrupt Mask Register - TIMSK The Timer/Counter Interrupt Flag Register - TIFR External Interrupt Pin Change Interrupt The MCU Control Register - MCUCR Sleep Modes Idle Mode ADC Noise Reduction Mode Power-down Mode Tuneable Internal RC Oscillator The System Clock Oscillator Calibration Register - OSCCAL Internal PLL for Fast Peripheral Clock Generation Timer/Counters The Timer/Counter0 Prescaler The Timer/Counter1 Prescaler The Special Function IO Register - SFIOR The 8-bit Timer/Counter0 The Timer/Counter0 Control Register - TCCR0 The Timer Counter 0 - TCNT0 The 8-bit Timer/Counter1 The Timer/Counter1 Control Register - TCCR1 The Timer/Counter1 - TCNT1 Timer/Counter1 Output Compare RegisterA - OCR1A Timer/Counter1 in PWM Mode Timer/Counter1 Output Compare RegisterB - OCR1B The Watchdog Timer The Watchdog Timer Control Register - WDTCR EEPROM Read/Write Access The EEPROM Address Register - EEAR The EEPROM Data Register - EEDR The EEPROM Control Register - EECR Preventing EEPROM Corruption The Analog Comparator The Analog Comparator Control and Status Register - ACSR The Analog-to-Digital Converter, Analog Multiplexer, and Gain Stages Features Operation Prescaling and Conversion Timing ADC Noise Canceler Function The ADC Multiplexer Selection Register - ADMUX The ADC Control and Status Register - ADCSR The ADC Data Register - ADCL and ADCH ADLAR = 0 ADLAR = 1 Scanning Multiple Channels ADC Noise-canceling Techniques ADC Characteristics I/O Port B Unconnected Pins Alternative Functions of Port B The Port B Data Register - PORTB The Port B Data Direction Register - DDRB The Port B Input Pins Address - PINB PORT B as General Digital I/O Alternate Functions of Port B Memory Programming Program and Data Memory Lock Bits Fuse Bits Signature Bytes Calibration Byte Programming the Flash High-voltage Serial Programming High-voltage Serial Programming Algorithm High-voltage Serial Programming Characteristics Low-voltage Serial Downloading Low-voltage Serial Programming Algorithm Data Polling Low-voltage Serial Programming Characteristics Electrical Characteristics Absolute Maximum Ratings DC Characteristics Typical Characteristics ATtiny15L Register Summary ATtiny15L Instruction Set Summary Ordering Information Packaging Information 8P3 8S2 Datasheet revision history Rev H - 09/07 Rev G - 06/07 Rev F - 06/05 Table of Contents