158
8331B–AVR–03/12
Atmel AVR XMEGA AU
• Bit 2:0 – ISC[2:0]: Input/Sense Configuration
These bits set the input and sense configuration on pin n according to
. The sense
configuration decides how the pin can trigger port interrupts and events. If the input buffer is not
disabled, the input cannot be read in the IN register.
Note:
1. A low-level pin value will not generate events, and a high-level pin value will continuously gen-
erate events.
2. Only PORTA - PORTF support the input buffer disable option. If the pin is used for analog func-
tionality, such as AC or ADC, it is recommended to configure the pin to INPUT_DISABLE.
Table 13-5.
Output/pull configuration.
OPC[2:0]
Group Configuration
Description
Output Configuration
Pull Configuration
000
TOTEM
Totem-pole
(N/A)
001
BUSKEEPER
Totem-pole
Bus-keeper
010
PULLDOWN
Totem-pole
Pull-down (on input)
011
PULLUP
Totem-pole
Pull-up (on input)
100
WIREDOR
Wired-OR
(N/A)
101
WIREDAND
Wired-AND
(N/A)
110
WIREDORPULL
Wired-OR
Pull-down
111
WIREDANDPULL
Wired-AND
Pull-up
Table 13-6.
Input/sense configuration.
ISC[2:0]
Group Configuration
Description
000
BOTHEDGES
Sense both edges
001
RISING
Sense rising edge
010
FALLING
Sense falling edge
011
LEVEL
Sense low level
100
Reserved
101
Reserved
110
Reserved
111
INTPUT_DISABLE
Digital input buffer disabled