9.3.5 Alternate Functions of Port E
The Port E pins with alternate functions are shown in Table 9-12.
Table 9-12. Port E Pins Alternate Functions
Port Pin
Alternate Function
XTAL2 (XTAL Output)
PE2
ADC0 (Analog Input Channel 0)
PCINT26 (Pin Change Interrupt 26)
XTAL1 (XTAL Input)
PE1
PE0
OC0B (Timer 0 Output Compare B)
PCINT25 (Pin Change Interrupt 25)
RESET# (Reset Input)
OCD (On Chip Debug I/O)
PCINT24 (Pin Change Interrupt 24)
Note:
On the engineering samples (Parts marked AT90PWM324), the ACMPN3 alternate function is not located on
PC4. It is located on PE2.
The alternate pin configuration is as follows:
• PCINT26/XTAL2/ADC0 – Bit 2
XTAL2: Chip clock oscillator pin 2. Used as clock pin for crystal oscillator or low-frequency crystal oscillator. When used as a
clock pin, the pin can not be used as an I/O pin.
ADC0, analog to digital converter, input channel 0.
PCINT26, pin change interrupt 26.
• PCINT25/XTAL1/OC0B – Bit 1
XTAL1: Chip clock oscillator pin 1. Used for all chip clock sources except internal calibrated RC oscillator. When used as a
clock pin, the pin can not be used as an I/O pin.
OC0B, output compare Match B output: This pin can serve as an external output for the Timer/Counter0 output compare B.
The pin has to be configured as an output (DDE1 set “one”) to serve this function. This pin is also the output pin for the PWM
mode timer function.
PCINT25, pin change interrupt 25.
• PCINT24/RESET/OCD – Bit 0
RESET, reset pin: When the RSTDISBL Fuse is programmed, this pin functions as a normal I/O pin, and the part will have to
rely on power-on reset and brown-out reset as its reset sources. When the RSTDISBL Fuse is unprogrammed, the reset
circuitry is connected to the pin, and the pin can not be used as an I/O pin.
If PE0 is used as a reset pin, DDE0, PORTE0 and PINE0 will all read 0.
PCINT24, pin change interrupt 24.
ATmega16/32/64/M1/C1 [DATASHEET]
67
7647O–AVR–01/15
MICROCHIP [ MICROCHIP ]
