Error handling in embedded projects in Arduino - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if a sensor reading is valid before using it.

Arduino

int sensorValue = analogRead(A0);
if (sensorValue [1] 0) {
  Serial.println("Sensor reading is valid.");
}

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

A>

B<

C==

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of '>' causes the check to only pass if sensorValue is exactly zero.

Using '<' will check for negative values, which sensorValue cannot be.

We check if the sensor value is greater than 0 to ensure it is valid.

2fill in blank

medium

Complete the code to retry reading the sensor if the value is invalid (zero).

Arduino

int sensorValue = 0;
while (sensorValue [1] 0) {
  sensorValue = analogRead(A1);
  delay(100);
}

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

A==

B>

C<

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' will cause the loop to run when sensorValue is not zero, which is wrong.

Using '>' or '<' will not correctly check for zero.

The loop continues while sensorValue equals zero, retrying the read.

3fill in blank

hard

Fix the error in the code to handle sensor failure by setting an error flag.

Arduino

bool errorFlag = false;
int sensorValue = analogRead(A2);
if (sensorValue [1] 0) {
  errorFlag = true;
}

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

A<

B>

C==

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' will set errorFlag when sensorValue is anything but 0.

Using '>' or '<' will not correctly detect the error code.

We check if sensorValue equals 0, which indicates a failure.

4fill in blank

hard

Fill the blank to set the sensor status if value is above threshold.

Arduino

const int threshold = 500;
int sensorValue = analogRead(A4);
String sensorStatus = (sensorValue [1] threshold) ? "OK" : "FAIL";

void setup() {
  Serial.begin(9600);
  Serial.println("Sensor status: " + sensorStatus);
}

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

A<

B>

C==

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' will invert the logic.

Using '==' or '!=' will only check equality, not greater than.

The ternary operator checks if sensorValue is greater than threshold to set status.

5fill in blank

hard

Fill all three blanks to log error messages only when errorFlag is true and sensorValue is invalid.

Arduino

bool errorFlag = false;
int sensorValue = analogRead(A3);

if (sensorValue [1] 0) {
  errorFlag = true;
}

if (errorFlag [2] true && sensorValue [3] 0) {
  Serial.println("Error: Sensor failure detected.");
}

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

A==

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' will invert the logic and cause wrong behavior.

Mixing operators will cause syntax or logic errors.

All conditions check equality to detect error and print message.