Datasheet

109
ATmega640/1280/1281/2560/2561
2549K–AVR–01/07
Alternate Functions of Port J The Port J alternate pin configuration is as follows:
• PCINT15:12 - Port J, Bit 6:3
PCINT15:12, Pin Change Interrupt Source 15:12. The PJ6:3 pins can serve as External
Interrupt Sources
• XCK2/PCINT11 - Port J, Bit 2
XCK2, USART 2 External Clock. The Data Direction Register (DDJ2) controls whether
the clock is output (DDJ2 set) or input (DDJ2 cleared). The XCK2 pin is active only when
the USART2 operates in synchronous mode.
PCINT11, Pin Change Interrupt Source 11. The PJ2 pin can serve as External Interrupt
Sources
• TXD3/PCINT10 - Port J, Bit 1
TXD3, USART3 Transmit pin
PCINT10, Pin Change Interrupt Source 10. The PJ1 pin can serve as External Interrupt
Sources
• RXD3/PCINT9 - Port J, Bit 0
RXD3, USART3 Receive pin. Receive Data (Data input pin for the USART3). When the
USART3 Receiver is enabled, this pin is configured as an input regardless of the value
of DDJ0. When the USART3 forces this pin to be an input, a logical one in PORTJ0 will
turn on the internal pull-up.
PCINT9, Pin Change Interrupt Source 9. The PJ0 pin can serve as External Interrupt
Sources
Table 64 and Table 65 relates the alternate functions of Port J to the overriding signals
shown in Figure 36 on page 89
Table 63. Port J Pins Alternate Functions
Port Pin Alternate Function
PJ7 –
PJ6 PCINT15 (Pin Change Interrupt 15)
PJ5 PCINT14 (Pin Change Interrupt 14)
PJ4 PCINT13 (Pin Change Interrupt 13)
PJ3 PCINT12 (Pin Change Interrupt 12)
PJ2 XCK3/PCINT11 (USART3 External Clock or Pin Change Interrupt 11)
PJ1 TXD3/PCINT10 (USART3 Transmit Pin or Pin Change Interrupt 10)
PJ0 RXD3/PCINT9 (USART3 Receive Pin or Pin Change Interrupt 9)