75
2552K–AVR–04/11
ATmega329/3290/649/6490
13.3.5
Alternate Functions of Port E
The Port E pins with alternate functions are shown in
Table 13-15. PCINT7 – Port E, Bit 7
PCINT7, Pin Change Interrupt Source 7: The PE7 pin can serve as an external interrupt source.
CLKO, Divided System Clock: The divided system clock can be output on the PE7 pin. The
divided system clock will be output if the CKOUT Fuse is programmed, regardless of the
PORTE7 and DDE7 settings. It will also be output during reset.
DO/PCINT6 – Port E, Bit 6
DO, Universal Serial Interface Data output.
PCINT6, Pin Change Interrupt Source 6: The PE6 pin can serve as an external interrupt source.
DI/SDA/PCINT5 – Port E, Bit 5
DI, Universal Serial Interface Data input.
SDA, Two-wire Serial Interface Data:
PCINT5, Pin Change Interrupt Source 5: The PE5 pin can serve as an external interrupt source.
USCK/SCL/PCINT4 – Port E, Bit 4
USCK, Universal Serial Interface Clock.
SCL, Two-wire Serial Interface Clock.
PCINT4, Pin Change Interrupt Source 4: The PE4 pin can serve as an external interrupt source.
AIN1/PCINT3 – Port E, Bit 3
AIN1 – Analog Comparator Negative input. This pin is directly connected to the negative input of
the Analog Comparator.
PCINT3, Pin Change Interrupt Source 3: The PE3 pin can serve as an external interrupt source.
Table 13-15. Port E Pins Alternate Functions
Port Pin
Alternate Function
PE7
PCINT7 (Pin Change Interrupt7)
CLKO (Divided System Clock)
PE6
DO/PCINT6 (USI Data Output or Pin Change Interrupt6)
PE5
DI/SDA/PCINT5 (USI Data Input or TWI Serial DAta or Pin Change Interrupt5)
PE4
USCK/SCL/PCINT4 (USART0 External Clock Input/Output or TWI Serial Clock
or Pin Change Interrupt4)
PE3
AIN1/PCINT3 (Analog Comparator Negative Input or Pin Change Interrupt3)
PE2
XCK/AIN0/ PCINT2 (USART0 External Clock or Analog Comparator Positive
Input or Pin Change Interrupt2)
PE1
TXD/PCINT1 (USART0 Transmit Pin or Pin Change Interrupt1)
PE0
RXD/PCINT0 (USART0 Receive Pin or Pin Change Interrupt0)