Ring buffer implementation in Embedded C - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare the ring buffer size constant.

Embedded C

const int BUFFER_SIZE = [1];

Drag options to blanks, or click blank then click option'

A128

B256

Csize

Dbuffer_size

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name instead of a numeric constant.

The ring buffer size is set as a constant integer value. Here, 128 is a common buffer size.

2fill in blank

medium

Complete the code to declare the ring buffer array.

Embedded C

char ring_buffer[[1]];

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ABUFFER_SIZE

Bbuffer

Csize

D128

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name that is not defined.

The ring buffer array is declared with the size constant BUFFER_SIZE.

3fill in blank

hard

Fix the error in the function to check if the ring buffer is empty.

Embedded C

int is_empty() {
    return [1] == tail;
}

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Asize

Bbuffer

Ccount

Dhead

Attempts:

3 left

💡 Hint

Common Mistakes

Comparing wrong variables like buffer or count.

The ring buffer is empty when the head index equals the tail index.

4fill in blank

hard

Fill both blanks to correctly advance the head index in the ring buffer.

Embedded C

head = (head [1] 1) [2] BUFFER_SIZE;

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A+

B-

C%

D/

Attempts:

3 left

💡 Hint

Common Mistakes

Using subtraction or division instead of addition and modulo.

The head index is incremented by 1 and wrapped around using modulo BUFFER_SIZE.

5fill in blank

hard

Fill all three blanks to implement the function that adds a character to the ring buffer safely.

Embedded C

int enqueue(char c) {
    if ((head [1] 1) [2] BUFFER_SIZE == tail) {
        return 0; // Buffer full
    }
    ring_buffer[head] = c;
    head = (head [3] 1) % BUFFER_SIZE;
    return 1;
}

Drag options to blanks, or click blank then click option'

A+

B-

C%

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using subtraction or multiplication instead of addition and modulo.

The function checks if the buffer is full by seeing if incrementing head wraps to tail. It uses addition and modulo to update the head index safely.