ATmega88PA Automotive Atmel Corporation, ATmega88PA Automotive Datasheet - Page 5

• Manufacturer Part Number: ATmega88PA Automotive
• Manufacturer: Atmel Corporation

2.3
2.3.1
2.3.2
2.3.3
2.3.4
2.3.5
7701E–AVR–02/11
Pin Descriptions
VCC
GND
Port B (PB3...PB0)
RESET
Port A (PA7...PA0)
Supply voltage.
Ground.
Port B is a 4-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port B output buffers have symmetrical drive characteristics with both high sink and source
capability except PB3, which has the RESET capability. To use pin PB3 as an I/O pin instead
of RESET pin, program (‘0’) RSTDISBL fuse. As inputs, Port B pins that are externally pulled
low will source current if the pull-up resistors are activated. The Port B pins are tri-stated when
a reset condition becomes active, even if the clock is not running.
Port B also serves the functions of various special features of the Atmel
listed on
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. The minimum pulse length is given in
42. Shorter pulses are not guaranteed to generate a reset.
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 an alternate function as analog input for the ADC, analog comparator, timer/coun-
ter, SPI and pin change interrupt as described in
page
61.
Section 12.3 “Alternate Port Functions” on page
Atmel ATtiny24/44/84 [Preliminary]
Section 12.3 “Alternate Port Functions” on
61.
®
ATtiny24/44/84 as
Table 9-1 on page
5