ATtiny24A/44A
Port B also serves the functions of various special features of the ATtiny24A/44A as listed in
Section 10.2 “Alternate Port Functions” on page 57.
1.1.4
RESET
Reset input. A low level on this pin for longer than the minimum pulse length will generate a
reset, even if the clock is not running and provided the reset pin has not been disabled. The min-
imum pulse length is given in
Table 20-4 on page 176.
Shorter pulses are not guaranteed to
generate a reset.
The reset pin can also be used as a (weak) I/O pin.
1.1.5
Port A (PA7...PA0)
Port A is a 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port A output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port A pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port A pins are tri-stated when a reset condition becomes active,
even if the clock is not running.
Port A has alternate functions as analog inputs for the ADC, analog comparator, timer/counter,
SPI and pin change interrupt as described in
“Alternate Port Functions” on page 57.
3
8183AS–AVR–12/08
ATMEL [ ATMEL CORPORATION ]
