attiny13-20ss ATMEL Corporation, attiny13-20ss Datasheet - Page 48

• Manufacturer Part Number: attiny13-20ss
• Description: 8-bit Microcontroller With 1k Bytes In-system Programmable Flash - Atmel Corporation
• Manufacturer: ATMEL Corporation

Unconnected Pins
Alternate Port Functions
48
ATtiny13
when resuming from the above mentioned Sleep mode, as the clamping in these sleep
mode 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, floating 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
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. Figure
24 shows how the port pin control signals from the simplified Figure 21 can be overrid-
den by alternate 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 micro-
controller family.
CC
or GND is not recommended, since this may
2535G–AVR–01/07