Common errors while using Arduino

When making a project at either beginner or advanced level there are chances that you encounter errors. The errors can be either related to the Arduino code or to the hardware of the project and these issues can be overcomed if we keep in mind a few things. By remembering somecommon things can save us a lot of time and effort. So, we have listed down some of the common mistakes done by the beginners while working on the Arduino in a project.

What are the common errors while using Arduino?

The errors encountered while working on Arduino include the errors either while programming the Arduino board or when assembling the hardware of any project. Below we have provided the list of common mistakes made by the beginners when making a project and their solutions so that these mistakes can be avoided in the first place:

  • Syntax error in Arduino code
  • Declaration error in the Arduino code
  • Missing libraries in the Arduino code
  • Use of TX and RX pin while uploading the code
  • Port selection for uploading the code

Syntax errors in Arduino code

The most common mistake that is seen while compiling the Arduino code is the syntax error and it is encountered due to the following reasons

  • Missing semicolon at the end of any statement
  • Missing bracket either at the end or start of the loop or statement

These errors can be avoided in such a way that whenever writing any loop, start writing inside the brackets from the beginning. Also, when writing the code in Arduino IDE keep checking if there is any code line highlighted in red and if there is rectify it first before compiling.

Declaration error in Arduino code

Another error that is mostly seen while compiling the Arduino code is the using variables in the code that are not given the data types and the error ”not declared in the scope” is encountered. There are two reasons for such type of errors that are:

  • Calling local variables in any function
  • Using undefined variables in a function

The variables that are defined outside the setup and loop functions are the global function that can be accessed anywhere in the Arduino code. Whereas the variables declared either in the loop section or in the setup function are called the local variables as they cannot be accessed from outside the respective functions.

To avoid the chance of occurrence of such errors one should always make a habit of declaring the variable at the start of the program. To understand more about this error you must read what is the error “not declared in this scope”.

Missing libraries in the Arduino code

To connect a device with an Arduino mostly library for that device is required in order to get it recognized by the Arduino board. Whenever there is a library missing in the Arduino code the error “no file or directory“ is encountered and the there is one reason for it that is:

  • Libraries not installed of the respective connected device

To resolve or to avoid this error one has to first install the respective library using the library manager of the Arduino IDE. To understand how to add libraries in Arduino IDE you must read. The header file name written in the Arduino code of the library should also be correct of the respective library being installed in the Arduino IDE.

Use of TX and RX pin while uploading the code

When a communication device is being used in a project that is connected to the TX and RX pin, the program will not be uploaded to the Arduino board. In this case you will see this error that says “programmer not responding” and this error pops up because to upload the code from the computer the Arduino board uses its TX and RX connections.

This error can be avoided by disconnecting the TX and RX pin of the device from the Arduino board while uploading the code to the board.

Port selection for uploading the code

Sometimes when uploading the Arduino code there is an error that says “no upload port provided” which means that code has been compiled but there is no port selected through which the code would upload to the Arduino board. You can choose the port by selecting the port form the menu at the top of Arduino IDE as shown in the figure below:

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To avoid getting errors when compiling and uploading the Arduino code we should remember a list of to do things whenever making a project using Arduino. Doing this will keep beginners out of the trouble caused by errors. We have explained some of the most common errors that can be avoided if we can keep in mind the 5 things we described.

About the author

Aaliyan Javaid

I am an electrical engineer and a technical blogger. My keen interest in embedded systems has led me to write and share my knowledge about them.