AND for masking bits in Embedded C - Mini Project: Build & Apply

AND for Masking Bits in Embedded C

📖 Scenario: You are working with a microcontroller that reads sensor data packed into a single byte. Each bit in this byte represents a different sensor's status (on or off). You need to extract the status of specific sensors by masking bits.

🎯 Goal: Learn how to use the AND operator to mask bits and extract specific sensor statuses from a byte.

📋 What You'll Learn

Create a variable called sensor_data with the exact value 0b10101100 (binary literal).

Create a variable called mask with the exact value 0b00000100 to select the third bit.

Use the AND operator with sensor_data and mask to create a variable called masked_result.

Print the value of masked_result as an integer.

💡 Why This Matters

🌍 Real World

Microcontrollers often pack multiple sensor statuses into one byte. Masking bits helps read each sensor's status separately.

💼 Career

Embedded systems engineers use bit masking to efficiently handle hardware signals and sensor data.

1

Create the sensor data variable

Create an unsigned 8-bit variable called sensor_data and set it to the binary value 0b10101100.

Embedded C

# Create the sensor_data variable with value 0b10101100
// Your code here

Need a hint?

Use unsigned char for an 8-bit variable and binary literal 0b10101100.

2

Create the mask variable

Create an unsigned 8-bit variable called mask and set it to the binary value 0b00000100 to select the third bit.

Embedded C

unsigned char sensor_data = 0b10101100;
// Create the mask variable with value 0b00000100
// Your code here

Need a hint?

The mask should have only the third bit set to 1.

3

Apply the AND operator to mask bits

Use the AND operator & with sensor_data and mask to create an unsigned 8-bit variable called masked_result.

Embedded C

unsigned char sensor_data = 0b10101100;
unsigned char mask = 0b00000100;
// Use AND operator to mask bits and store in masked_result
// Your code here

Need a hint?

The AND operator & keeps bits that are 1 in both variables.

4

Print the masked result

Write a printf statement to print the value of masked_result as an integer.

Embedded C

unsigned char sensor_data = 0b10101100;
unsigned char mask = 0b00000100;
unsigned char masked_result = sensor_data & mask;
// Print masked_result as an integer
// Your code here

Need a hint?

Use printf("%d\n", masked_result); inside main().