
57
2503Q–AVR–02/11
ATmega32(L)
Alternate Functions of
Port B
The Port B pins with alternate functions are shown in
Table 25.The alternate pin configuration is as follows:
SCK – Port B, Bit 7
SCK: Master Clock output, Slave Clock input pin for SPI. When the SPI is enabled as a Slave,
this pin is configured as an input regardless of the setting of DDB7. When the SPI is enabled as
a Master, the data direction of this pin is controlled by DDB7. When the pin is forced by the SPI
to be an input, the pull-up can still be controlled by the PORTB7 bit.
MISO – Port B, Bit 6
MISO: Master Data input, Slave Data output pin for SPI. When the SPI is enabled as a Master,
this pin is configured as an input regardless of the setting of DDB6. When the SPI is enabled as
a Slave, the data direction of this pin is controlled by DDB6. When the pin is forced by the SPI to
be an input, the pull-up can still be controlled by the PORTB6 bit.
Table 24. Overriding Signals for Alternate Functions in PA3..PA0
Signal Name
PA3/ADC3
PA2/ADC2
PA1/ADC1
PA0/ADC0
PUOE
000
0
PUOV
000
0
DDOE
0
DDOV
0
PVOE
000
0
PVOV
000
0
DIEOE
000
0
DIEOV
000
0
DI
–––
–
AIO
ADC3 INPUT
ADC2 INPUT
ADC1 INPUT
ADC0 INPUT
Table 25. Port B Pins Alternate Functions
Port Pin
Alternate Functions
PB7
SCK (SPI Bus Serial Clock)
PB6
MISO (SPI Bus Master Input/Slave Output)
PB5
MOSI (SPI Bus Master Output/Slave Input)
PB4
SS (SPI Slave Select Input)
PB3
AIN1 (Analog Comparator Negative Input)
OC0 (Timer/Counter0 Output Compare Match Output)
PB2
AIN0 (Analog Comparator Positive Input)
INT2 (External Interrupt 2 Input)
PB1
T1 (Timer/Counter1 External Counter Input)
PB0
T0 (Timer/Counter0 External Counter Input)
XCK (USART External Clock Input/Output)