6. AVR Pin Assignment Table Sorted by Function
Function
ATmega324/1284 Pin
free analog input and digital I/O (x8)
PA0 – PA7
free digital I/O (x8)
PB3, PC0, PC1, PD0 – PD4, PD5**
free digital output
PB4*
free PWM outputs (x2)
PB3, PB4
red user LED
PD1
green user LED
PC4
UART0
PD0, PD1
UART1
PD2, PD3
user pushbuttons (bottom to top, x3)
PC2, PC3, PC5
motor 1 (direction, speed)
PC7, PD7
motor 2 (direction, speed)
PC6, PD6
buzzer
PD4
LCD control (RS, R/W, E)
PB0, PB1, PB2
LCD data (4-bit: DB4 – DB7)
PC2 – PC5
SPI auxiliary processor control lines (x3) PB5, PB6, PB7
ICSP programming lines (x3)
PB5, PB6, PB7
ADC reference pin
AREF
reset pushbutton
RESET
*
: Using PB4/SS as an input will interfere with communication to the auxiliary processor, so we
recommend using it as a digital output. See
Section 3.j
of the Pololu USB AVR C/C++ User’s Guide
for more information.
**
: PD5 is a free digital I/O unless you want to use the built-in servo pulse hardware.
Pololu Orangutan SVP User’s Guide
© 2001–2019 Pololu Corporation
6. AVR Pin Assignment Table Sorted by Function
Page 27 of 43
