Reading digital input pin state in Embedded C - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to read the state of a digital input pin.

Embedded C

int pinState = digitalRead([1]);

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A13

BOUTPUT

C5

DHIGH

Attempts:

3 left

💡 Hint

Common Mistakes

Using pin mode constants like OUTPUT or HIGH instead of a pin number.

Confusing digitalRead with digitalWrite.

The function digitalRead reads the state of the specified digital pin number. Pin 13 is commonly used for input or output on many boards.

2fill in blank

medium

Complete the code to check if the digital input pin reads HIGH.

Embedded C

if (digitalRead(7) == [1]) {
    // Pin is HIGH
}

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ALOW

BHIGH

CINPUT

DOUTPUT

Attempts:

3 left

💡 Hint

Common Mistakes

Comparing to pin mode constants like INPUT or OUTPUT.

Using LOW instead of HIGH in the condition.

To check if a pin is HIGH, compare the result of digitalRead to HIGH.

3fill in blank

hard

Fix the error in reading the digital input pin state.

Embedded C

pinMode(8, INPUT);
int state = digitalRead([1]);

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A8

B9

CINPUT

DHIGH

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different pin number than the one set as input.

Passing mode constants like INPUT or HIGH to digitalRead.

The pin number used in digitalRead must match the pin set as input with pinMode. Here, pin 8 is configured as input, so digitalRead should use 8.

4fill in blank

hard

Fill both blanks to read a digital input pin and check if it is LOW.

Embedded C

pinMode([1], INPUT);
if (digitalRead([2]) == LOW) {
    // Pin is LOW
}

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A4

BHIGH

D7

Attempts:

3 left

💡 Hint

Common Mistakes

Using different pin numbers in pinMode and digitalRead.

Comparing to HIGH instead of LOW.

Set pin 4 as input and read from pin 4 to check if it is LOW.

5fill in blank

hard

Fill all three blanks to read a digital input pin, store its state, and check if it is HIGH.

Embedded C

pinMode([1], INPUT);
int state = digitalRead([2]);
if (state == [3]) {
    // Pin is HIGH
}

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

A2

CHIGH

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Using different pin numbers in pinMode and digitalRead.

Comparing to LOW instead of HIGH.

The pin number used in pinMode and digitalRead must match. Here, set pin 2 as input, read from pin 2, and check if state is HIGH.