Rainbow Electronics ATmega161L - Manual (Page 107)

107
ATmega161(L)
1228C–AVR–08/02
Note: 1. n: 2,1,0, pin number.
Alternate Functions of Port E The alternate pin configuration is as follows:
• OC1B – Port E, Bit 2
OC1B, Output compare match output: The PE2 pin can serve as an external output
when the Timer/Counter1 compare matches. The PE2 pin has to be configured as an
output (DDE2 set [one]) to serve this function. See “Timer/Counter1” on page 49 for fur-
ther details. The OC1B pin is also the output pin for the PWM mode timer function.
• ALE – Port E, Bit 1
ALE: When the External Memory is enabled, the PE1 pin serves as the Dress Latch
Enable. Note that enabling of External Memory will override both the direction and port
value. See “Interface to External Memory” on page 84 for a detailed description.
• ICP/INT2 – Port E, Bit 0
ICP, Input Capture pin: The PE0 pin can serve as the Input Capture source for
Timer/Counter 1. See page 54 for a detailed description.
INT2, External Interrupt source 2: The PE0 pin can serve as an external interrupt source
to the MCU. See “Extended MCU Control Register – EMCUCR” on page 36 for further
details.
Table 36. DDEn Bits on Port E Pins (1)
DDEn PORTEn I/O Pull-up Comment
0 0 Input No Tri-state (high-Z)
0 1 Input Yes PEn will source current if ext. pulled low.
1 0 Output No Push-pull Zero Output
1 1 Output No Push-pull One Output