Teach lesson
Basic Arduino 1/4: make an LED blink
Students use a remote Arduino board to turn an external LED on and off, change the blink rate, and recognize setup() and loop().
Learning Outcomes
Identify setup() and loop() in an Arduino program.
Configure a digital pin as an output.
Change the blink rate of an LED.
Student activity preview
Activity Content
Preview only. In a class session, students can fill in responses and submit their work to the teacher.
Before programming
7 min
Arduino runs two main parts. setup() runs once when the board starts. loop() repeats again and again. On this board, external LED 1 is connected to digital pin 8. If you configure that pin as an output, the program can turn it on and off. This fragment shows the blink cycle you are going to test:
digitalWrite(led1, HIGH);
delay(1000);
digitalWrite(led1, LOW);
delay(1000);delay(1000) means a wait of 1000 milliseconds, or 1 second.
According to that fragment, if you change both delay(1000) lines to delay(250), what do you think will happen?
Program and observe
18 min
Open the lab, copy this program into main.ino, save it, and upload it to the board. When you see it working, change both delay(1000) lines to delay(250), save, and upload again.
const int led1 = 8;
void setup() {
pinMode(led1, OUTPUT);
}
void loop() {
digitalWrite(led1, HIGH);
delay(1000);
digitalWrite(led1, LOW);
delay(1000);
}Open the Arduino lab.
Copy or adapt the program in the editor.
Save the file.
Upload it to the board and observe LED 1.
Change both delays to 250 ms and upload again.
Submit your code
Capture the final code with the faster blink. Before attaching it, save main.ino in the lab environment. The snapshot must show the program you actually want your teacher to review.
Explain what you observed
10 min
Explain in your own words what pinMode, digitalWrite, and delay do in your program. Then describe what changed in the blink when you used delay(250) and whether it matched your first prediction.