Contents

Introduction Features Pin Functionality Difference Enhancement and Added Features Self-programming Flash USART Module Shorter Startup Time Improved Internal 8MHz RC Oscillator Accuracy Improved ADC Module Bandgap Reference Connected to Analog Comparator Additional Pin Change Interrupt Difference in Package Types Register Differences New Registers in ATtiny102/104 Port A Data Direction Register Port A Input Pins Address Port A Data Register Port A Pull-up Enable Control Register USART Baud Rate 0 Register High USART Baud Rate 0 Register Low USART Control and Status Register 0 A USART Control and Status Register 0 B USART Control and Status Register 0 C USART Control and Status Register 0 D USART I/O Data Register 0 Registers in ATtiny102/104 with Bit Differences Digital Input Disable Register 0 ADC Data Register High Byte (ADLAR=1) ADC Conversion Result Low Byte (ADLAR=1) Digital Input Disable Register 0 Pin Change Interrupt Control Register Pin Change Interrupt Flag Register Pin Change Mask Register 0 Pin Change Mask Register 1 Port Control Register Revision History Legal Disclaimer