pin atmega328p arduino elegoo direction 1 PC6 (PCINT14/RESET) reset n/a 2 PD0 (PCINT16/RXD) digital pin 0 (RX) n/a 3 PD1 (PCINT17/TXD) digital pin 1 (TX) n/a 4 PD2 (PCINT18/INT0) digital pin 2 ground sensor right in 5 PD3 (PCINT19/OC2B/INT1) digital pin 3 (PWM) ground sensor center in 6 PD4 (PCINT20/XCK/T0) digital pin 4 ground sensor left in 7 VCC VCC n/a 8 GND GND n/a 9 PB6 (PCINT6/XTAL1/TOSC1) crystal n/a 10 PB7 (PCINT7/XTAL2/TOSC2) crystal n/a 11 PD5 (PCINT21/OC0B/T1) digital pin 5 (PWM) motor enable right out pwm green 12 PD6 (PCINT22/OC0A/AIN0) digital pin 6 (PWM) motor enable left out pwm black 13 PD7 (PCINT23/AIN1) digital pin 7 direction backward right out blue 14 PB0 (PCINT0/CLKO/ICP1) digital pin 8 direction forward right out lila 15 PB1 (OC1A/PCINT1) digital pin 9 (PWM) direction backward left out gray 16 PB2 (SS/OC1B/PCINT2) digital pin 10 (PWM) direction forward left out white 17 PB3 (MOSI/OC2A/PCINT3) digital pin 11 (PWM) ultrasonic servo out ppm 18 PB4 (MISO/PCINT4) digital pin 12 infrared receiver in 19 PB5 (SCK/PCINT5) digital pin 13 (LED) n/a 20 AVCC VCC n/a 21 AREF analog reference n/a 22 GND GND n/a 23 PC0 (ADC0/PCINT8) analog input 0 ultrasonic trigger out 24 PC1 (ADC1/PCINT9) analog input 1 ultrasonic echo in 25 PC2 (ADC2/PCINT10) analog input 2 free 26 PC3 (ADC3/PCINT11) analog input 3 free 27 PC4 (ADC4/SDA/PCINT12) analog input 4 free 28 PC5 (ADC5/SCL/PCINT13) analog input 5 free # new setup 4 PD2 (PCINT18/INT0) digital pin 2 infrared receiver in 5 PD3 (PCINT19/OC2B/INT1) digital pin 3 (PWM) motor enable right out pwm 8-bit green 6 PD4 (PCINT20/XCK/T0) digital pin 4 direction forward left out white 11 PD5 (PCINT21/OC0B/T1) digital pin 5 (PWM) direction forward right out lila 12 PD6 (PCINT22/OC0A/AIN0) digital pin 6 (PWM) direction backward left out gray 13 PD7 (PCINT23/AIN1) digital pin 7 direction backward right out blue 14 PB0 (PCINT0/CLKO/ICP1) digital pin 8 ground sensor left in 15 PB1 (OC1A/PCINT1) digital pin 9 (PWM) ultrasonic servo out ppm 16-bit 16 PB2 (SS/OC1B/PCINT2) digital pin 10 (PWM) ground sensor center in 17 PB3 (MOSI/OC2A/PCINT3) digital pin 11 (PWM) motor enable left out pwm 8-bit black 18 PB4 (MISO/PCINT4) digital pin 12 ground sensor right in 23 PC0 (ADC0/PCINT8) analog input 0 ultrasonic trigger out 24 PC1 (ADC1/PCINT9) analog input 1 ultrasonic echo in 25 PC2 (ADC2/PCINT10) analog input 2 free 26 PC3 (ADC3/PCINT11) analog input 3 free 27 PC4 (ADC4/SDA/PCINT12) analog input 4 free 28 PC5 (ADC5/SCL/PCINT13) analog input 5 free