Handling errors

How to:

Let’s say your Arduino’s reading a sensor that may occasionally produce out-of-range values. Here’s how you might handle that:

int sensorValue = analogRead(A0);

if (sensorValue >= 0 && sensorValue <= 1023) {
  // Value is within range, proceed with processing
} else {
  // Value is out of range, handle the error
  Serial.println("Error: Sensor value out of range.");

Sample Output:

Error: Sensor value out of range.

Deep Dive

Error handling hasn’t always been so straightforward. In the early days, developers often ignored errors, leading to the dreaded “undefined behavior.” As programming evolved, so did the tools — you now have exceptions in many languages, but they’re still an old-school ‘check-it-first’ in the Arduino world due to hardware constraints and C++ roots.

In Arduino programming, you often see if-else statements for error handling. But there are alternatives: using the assert function to stop execution if a condition fails or designing fail-safes within your hardware setup itself.

When implementing error handling, consider the impact of stopping the program versus allowing it to continue with a default or safe state. There’s a trade-off, and the right choice depends on the potential harm of interruptions versus incorrect operation.

See Also

Brush up on error detection and handling with these:

This should give you the know-how and confidence to avoid the pitfalls of errors in your Arduino adventures.