Rainbow Electronics ATmega128L - Manual (Page 69)

69
ATmega128(L)
2467B–09/01
Alternate Functions of Port B The Port B pins with alternate functions are shown in Table 30.
Note: 1. OC1C not applicable in ATmega103 compatibility mode.
The alternate pin configuration is as follows:
• OC2/OC1C, Bit 7
OC2, Output Compare match output: The PB7 pin can serve as an external output for
the Timer/Counter2 output compare. The pin has to be configured as an output (DDB7
set “one”) to serve this function. The OC2 pin is also the output pin for the PWM mode
timer function.
OC1C, Output Compare matchC output: The PB7 pin can serve as an external output
for the Timer/Counter1 output compareC. The pin has to be configured as an output
(DDB7 set (one)) to serve this function. The OC1C pin is also the output pin for the
PWM mode timer function.
Table 29. Overriding Signals for Alternate Functions in PA3..PA0
Signal
Name
PA3/AD3 PA2/AD2 PA1/AD1 PA0/AD0
PUOE SRE SRE SRE SRE
PUOV ~(WR | ADA) •
PORTA3 • PUD ~(WR | ADA) •
PORTA2 • PUD ~(WR | ADA) •
PORTA1 • PUD ~(WR | ADA) •
PORTA0 • PUD
DDOE SRE SRE SRE SRE
DDOV WR | ADA WR | ADA WR | ADA WR | ADA
PVOE SRE SRE SRE SRE
PVOV A3 • ADA | D3
OUTPUT • WR A2• ADA | D2
OUTPUT • WR A1 • ADA | D1
OUTPUT • WR A0 • ADA | D0
OUTPUT • WR
DIEOE 0 0 0 0
DIEOV 0 0 0 0
DI D3 INPUT D2 INPUT D1 INPUT D0 INPUT
AIO – – – –
Table 30. Port B Pins Alternate Functions
Port Pin Alternate Functions
PB7
OC2/OC1C (1) (Output Compare and PWM Output for Timer/Counter2 or Output
Compare and PWM Output C for Timer/Counter1)
PB6 OC1B (Output Compare and PWM Output B for Timer/Counter1)
PB5 OC1A (Output Compare and PWM Output A for Timer/Counter1)
PB4 OC0 (Output Compare and PWM Output for Timer/Counter0)
PB3 MISO (SPI Bus Master Input/Slave Output)
PB2 MOSI (SPI Bus Master Output/Slave Input)
PB1 SCK (SPI Bus Serial Clock)
PB0 SS (SPI Slave Select input)