Original code here
int led = 10; void setup() { pinMode(led, OUTPUT); } void loop() { digitalWrite(led, HIGH); delay(1000); digitalWrite(led, LOW); delay(1000); }
Modification here
int led = 10; int led2 = 9; int led3 = 8; void setup(){ pinMode(led, OUTPUT); pinMode(led2, OUTPUT); pinMode(led3, OUTPUT); } void loop() { digitalWrite(led, HIGH); digitalWrite(led2,LOW); digitalWrite(led3, HIGH); delay(1000); digitalWrite(led3, LOW); digitalWrite(led2, HIGH); digitalWrite(led, LOW); delay(1000); }