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ATtiny40 [DATASHEET]
8263B–AVR–01/2013
10.3.3
Alternate Functions of Port C
The Port C pins with alternate function are shown in
Table 10-10. Port C, Bit 0 – OC0A/PCINT12
OC0A: Output Compare Match output. Provided that the pin has been configured as an output it serves as an
external output for Timer/Counter0 Compare Match A. This pin is also the output for the timer/counter PWM
mode function.
SS: Slave Select Input. Regardless of DDC0, this pin is automatically configured as an input when SPI is
enabled as a slave. The data direction of this pin is controlled by DDC0 when SPI is enabled as a master.
PCINT12: Pin Change Interrupt source 12. The PC0 pin can serve as an external interrupt source for pin
change interrupt 2.
Port C, Bit 1 – SCK/SCL/ICP1/T1/PCINT13
SCK: SPI Clock.
SCL: TWI Clock. The pin is disconnected from the part and becomes the serial clock for the TWI when TWEN in
TWSCRA is set. In this mode of operation, the pin is driven by an open drain driver with slew rate limitation and
a spike filter.
ICP1: Timer/Counter1 Input Capture Pin.
T1: Timer/Counter1 counter source.
PCINT13: Pin Change Interrupt source 13. The PC1 pin can serve as an external interrupt source for pin
change interrupt 2.
Port C, Bit 2 – INT0/CLKO/MISO/PCINT14
Table 10-10. Port A Pins Alternate Functions
Port Pin
Alternate Function
PC0
OC0A:
Timer/Counter0 Compare Match A output
SS :
SPI Slave Select
PCINT12:Pin Change Interrupt 0, Source 12
PC1
SCK:
SPI Clock
SCL :
TWI Clock
ICP1:
Timer/Counter1 Input Capture Pin
T1:
Timer/Counter1 Clock Source
PCINT13:Pin Change Interrupt 0, Source 13
PC2
INT0:
External Interrupt 0 Input
CLKO:
System Clock Output
MISO:
SPI Master Input / Slave Output
PCINT14:Pin Change Interrupt 0, Source 14
PC3
RESET: Reset pin
PCINT15:Pin Change Interrupt 0, Source 15
PC4
MOSI:
SPI Master Output / Slave Input
SDA:
TWI Data Input /Output
TPIDATA:Serial Programming Data
PCINT16:Pin Change Interrupt 0, Source 16
PC5
CLKI:
External Clock Input
TPICLK: Serial Programming Clock
PCINT17:Pin Change Interrupt 0, Source 17