atmega169pa-mcur ATMEL Corporation, atmega169pa-mcur Datasheet - Page 6

• Manufacturer Part Number: atmega169pa-mcur
• Description: High Performance, Low Power Avr 8-bit Microcontroller
• Manufacturer: ATMEL Corporation

2.2
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.2.6
8171BS–AVR–03/10
Pin Descriptions
VCC
GND
Port A (PA7:PA0)
Port B (PB7:PB0)
Port C (PC7:PC0)
Port D (PD7:PD0)
Digital supply voltage.
Ground.
Port A is an 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 also serves the functions of various special features of the ATmega169PA as listed on
”Alternate Functions of Port A” on page
Port B is an 8-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. 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 has better driving capabilities than the other ports.
Port B also serves the functions of various special features of the ATmega169PA as listed on
”Alternate Functions of Port B” on page
Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port C output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port C pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port C pins are tri-stated when a reset condition becomes active,
even if the clock is not running.
Port C also serves the functions of special features of the ATmega169PA as listed on
Functions of Port C” on page
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port D output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port D pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port D pins are tri-stated when a reset condition becomes active,
even if the clock is not running.
Port D also serves the functions of various special features of the ATmega169PA as listed on
”Alternate Functions of Port D” on page
76.
72.
73.
78.
ATmega169PA
”Alternate
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