//www.elegoo.com //2016.09.12 int ENA = 10; int IN1 = 9; int IN2 = 8; int IN3 = 7; int IN4 = 6; int ENB = 5; int SPEED = 100; void setup() { pinMode(IN1, OUTPUT); pinMode(IN2, OUTPUT); pinMode(IN3, OUTPUT); pinMode(IN4, OUTPUT); pinMode(ENA, OUTPUT); pinMode(ENB, OUTPUT); } void loop() { int i; digitalWrite(IN1, LOW); digitalWrite(IN2, HIGH); // left wheel goes forward digitalWrite(IN3, LOW); digitalWrite(IN4, HIGH); // right wheel goes forward for (i = 0; i < 256; i++) { analogWrite(ENA, i); analogWrite(ENB, i); delay(50); } for (i = 255; i >= 0; i--) { analogWrite(ENA, i); analogWrite(ENB, i); delay(50); } /* digitalWrite(IN1, LOW); digitalWrite(IN2, LOW); //left wheel holds still digitalWrite(IN3, LOW); digitalWrite(IN4, LOW); // right wheel holds still delay(500); digitalWrite(IN1, HIGH); digitalWrite(IN2, LOW); //left wheel is back up digitalWrite(IN3, HIGH); digitalWrite(IN4, LOW); // right wheel is back up delay(500); digitalWrite(IN1, LOW); digitalWrite(IN2, LOW); // left wheel holds still digitalWrite(IN3, LOW); digitalWrite(IN4, LOW); // right wheel holds still delay(500); */ }