Datasheet

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.
• T1 – Port D, Bit 5
T1, Timer/Counter1 counter source.
• XCK/T0 – Port D, Bit 4
XCK, USART external clock.
T0, Timer/Counter0 counter source.
• INT1 – Port D, Bit 3
INT1, External Interrupt source 1: The PD3 pin can serve as an external interrupt source.
• INT0 – Port D, Bit 2
INT0, External Interrupt source 0: The PD2 pin can serve as an external interrupt source.
• TXD – Port D, Bit 1
TXD, Transmit Data (Data output pin for the USART). When the USART Transmitter is enabled, this pin is
configured as an output regardless of the value of DDD1.
• RXD – Port D, Bit 0
RXD, Receive Data (Data input pin for the USART). When the USART Receiver is enabled this pin is
configured as an input regardless of the value of DDD0. When the USART forces this pin to be an input,
the pull-up can still be controlled by the PORTD0 bit.
The tables below relate the alternate functions of Port D to the overriding signals shown in figure Figure
18-5.
Table 18-10. Overriding Signals for Alternate Functions PD7:PD4
Signal
Name
PD7/AIN1 PD6/AIN0 PD5/T1 PD4/XCK/
T0
PUOE 0 0 0 0
PUO 0 0 0 0
OOE 0 0 0 0
OO 0 0 0 0
PVOE 0 0 0 UMSEL
PVO 0 0 0 XCK OUTPUT
DIEOE 0 0 0 0
DIEO 0 0 0 0
DI – – T1 INPUT XCK INPUT / T0 INPUT
AIO AIN1 INPUT AIN0 INPUT – –
AVR 8-Bit Microcontroller
I/O Ports
© 2017 Microchip Technology Inc.
Datasheet Complete
40001974A-page 92