Table 10-4. Overriding Signals for Alternate Functions in PB7..PB4
Signal
Name
PB7/XTAL2/
PB6/XTAL1/
PB5/SCK/
PCINT5
PB4/MISO/
PCINT4
TOSC2/PCINT7(1)
TOSC1/PCINT6(1)
INTRC • EXTCK+
AS2
PUOE
PUOV
DDOE
INTRC + AS2
0
SPE • MSTR
PORTB5 • PUD
SPE • MSTR
SPE • MSTR
PORTB4 • PUD
SPE • MSTR
0
INTRC • EXTCK+
AS2
INTRC + AS2
DDOV
PVOE
0
0
0
0
0
0
SPE • MSTR
SPE • MSTR
SPI SLAVE
OUTPUT
PVOV
0
0
SCK OUTPUT
PCINT5 • PCIE0
1
INTRC • EXTCK +
AS2 + PCINT7 •
PCIE0
INTRC + AS2 +
PCINT6 • PCIE0
DIEOE
PCINT4 • PCIE0
1
(INTRC + EXTCK) •
AS2
DIEOV
DI
INTRC • AS2
PCINT5 INPUT
SCK INPUT
PCINT4 INPUT
PCINT7 INPUT
Oscillator Output
PCINT6 INPUT
SPI MSTR INPUT
Oscillator/Clock
Input
AIO
–
–
Notes: 1. INTRC means that one of the internal RC Oscillators are selected (by the CKSEL fuses),
EXTCK means that external clock is selected (by the CKSEL fuses).
Table 10-5. Overriding Signals for Alternate Functions in PB3..PB0
Signal
Name
PB3/MOSI/
OC2/PCINT3
PB2/SS/
OC1B/PCINT2
PB1/OC1A/
PCINT1
PB0/ICP1/
PCINT0
PUOE
PUOV
DDOE
DDOV
SPE • MSTR
PORTB3 • PUD
SPE • MSTR
0
SPE • MSTR
PORTB2 • PUD
SPE • MSTR
0
0
0
0
0
0
0
0
0
SPE • MSTR +
OC2A ENABLE
PVOE
PVOV
OC1B ENABLE
OC1B
OC1A ENABLE
OC1A
0
0
SPI MSTR OUTPUT
+ OC2A
DIEOE
DIEOV
PCINT3 • PCIE0
1
PCINT2 • PCIE0
1
PCINT1 • PCIE0
1
PCINT0 • PCIE0
1
PCINT3 INPUT
PCINT2 INPUT
SPI SS
PCINT0 INPUT
ICP1 INPUT
DI
PCINT1 INPUT
–
SPI SLAVE INPUT
AIO
–
–
–
74
ATmega48/88/168
2545E–AVR–02/05
MICROCHIP [ MICROCHIP ]
