Writing HIGH and LOW to output pins in Embedded C - Mini Project: Build & Apply

Writing HIGH and LOW to Output Pins

📖 Scenario: You are working with a simple microcontroller board. You want to control two LEDs connected to output pins. One LED should be turned ON (HIGH) and the other LED should be turned OFF (LOW).

🎯 Goal: Write a program that sets two output pins: one to HIGH and the other to LOW, to control two LEDs.

📋 What You'll Learn

Create two variables representing output pins named pin1 and pin2 with values 5 and 6 respectively.

Create a variable called HIGH with value 1 and a variable called LOW with value 0.

Write code to set pin1 to HIGH and pin2 to LOW using a function called digitalWrite.

Print the states of pin1 and pin2 to the console.

💡 Why This Matters

🌍 Real World

Controlling LEDs or other devices by setting microcontroller pins HIGH or LOW is a basic task in embedded systems.

💼 Career

Embedded software engineers often write code to control hardware pins to turn devices on or off.

1

Define Output Pins

Create two integer variables called pin1 and pin2 and set them to 5 and 6 respectively.

Embedded C

# Define output pins
// Your code here

Need a hint?

Use int to declare the pins and assign the numbers 5 and 6.

2

Define HIGH and LOW Values

Create two integer variables called HIGH and LOW and set them to 1 and 0 respectively.

Embedded C

int pin1 = 5;
int pin2 = 6;
// Define HIGH and LOW values
// Your code here

Need a hint?

HIGH means ON (1), LOW means OFF (0).

3

Set Pins to HIGH and LOW

Use the function digitalWrite to set pin1 to HIGH and pin2 to LOW.

Embedded C

int pin1 = 5;
int pin2 = 6;
int HIGH = 1;
int LOW = 0;
// Set pin1 to HIGH and pin2 to LOW
// Your code here

Need a hint?

Call digitalWrite twice, once for each pin and value.

4

Print Pin States

Print the states of pin1 and pin2 using printf in the format: "Pin 5 is HIGH" and "Pin 6 is LOW".

Embedded C

int pin1 = 5;
int pin2 = 6;
int HIGH = 1;
int LOW = 0;
digitalWrite(pin1, HIGH);
digitalWrite(pin2, LOW);
// Print pin states
// Your code here

Need a hint?

Use printf with %d to insert pin numbers and print the states.