Alternate Port Functions - Atmel AVR AT90CAN32 Manual

9.2.6 Unconnected Pins
9.3

Alternate Port Functions

7679H–CAN–08/08
above mentioned sleep modes, as the clamping in these sleep modes produces the requested
logic change.
If some pins are unused, it is recommended to ensure that these pins have a defined level. Even
though most of the digital inputs are disabled in the deep sleep modes as described above, float-
ing inputs should be avoided to reduce current consumption in all other modes where the digital
inputs are enabled (Reset, Active mode and Idle mode). The simplest method to ensure a
defined level of an unused pin, is to enable the internal pull-up. In this case, the pull-up will be
disabled during reset. If low power consumption during reset is important, it is recommended to
use an external pull-up or pull-down. Connecting unused pins directly to V
ommended, since this may cause excessive currents if the pin is accidentally configured as an
output.
Most port pins have alternate functions in addition to being general digital I/Os.
how the port pin control signals from the simplified
functions. The overriding signals may not be present in all port pins, but the figure serves as a
generic description applicable to all port pins in the AVR microcontroller family.
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CC
Figure 9-2 can be overridden by alternate
or GND is not rec-
Figure 9-5 shows
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