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ATtiny20 [DATASHEET]
8235E–AVR–03/2013
Table 10-3. Port A Pins Alternate Functions
Port A, Bit 0 – ADC0/PCINT0
ADC0: Analog to Digital Converter, Channel 0.
PCINT0: Pin Change Interrupt source 0. The PA0 pin can serve as an external interrupt source for pin
change interrupt 0.
Port A, Bit 1 – ADC1/AIN0/PCINT1
ADC1: Analog to Digital Converter, Channel 1.
AIN0: Analog Comparator Positive Input. Configure the port pin as input with the internal pull-up switched off
to avoid the digital port function from interfering with the function of the Analog Comparator.
PCINT1: Pin Change Interrupt source 1. The PA1 pin can serve as an external interrupt source for pin
change interrupt 0.
Port A, Bit 2 – ADC2/AIN1/PCINT2
ADC2: Analog to Digital Converter, Channel 2.
AIN1: Analog Comparator Negative Input. Configure the port pin as input with the internal pull-up switched
off to avoid the digital port function from interfering with the function of the Analog Comparator.
Port Pin
Alternate Function
PA0
ADC0: ADC Input Channel 0
PCINT0: Pin Change Interrupt 0, Source 0
PA1
ADC1: ADC Input Channel 1
AIN0:
Analog Comparator, Positive Input
PCINT1:Pin Change Interrupt 0, Source 1
PA2
ADC2: ADC Input Channel 2
AIN1:
Analog Comparator, Negative Input
PCINT2: Pin Change Interrupt 0, Source 2
PA3
ADC3: ADC Input Channel 3
PCINT3: Pin Change Interrupt 0, Source 3
PA4
ADC4: ADC Input Channel 4
PCINT4: Pin Change Interrupt 0, Source 4
PA5
ADC5: ADC Input Channel 5
PCINT5: Pin Change Interrupt 0, Source 5
PA6
ADC6: ADC Input Channel 6
SS :
SPI Slave Select
PCINT6: Pin Change Interrupt 0, Source 6
PA7
ADC7: ADC Input Channel 7
OC0B:: Timer/Counter0 Compare Match B Output
ICP1:
Timer/Counter1 Input Capture Pin
T1:
Timer/Counter1 Clock Source
SCL:
TWI Clock
SCK:
SPI Clock
PCINT7: Pin Change Interrupt 0, Source 7