How to Choose an Arduino Shield
The king of prototyping
Arduino is arguably the most popular microcontroller that allows engineers, scholars, and designers to quickly prototype projects. It is an open-source platform consisting of both physical programmable circuit and an Integrated Development Environment (IDE) that runs on your PC enabling you to upload computer code to the board. Arduinos popularity is owed to the fact that it does not need a programmer so as to load new code onto to the board, you simply use a USB cable. The Arduino’s IDE uses a simplified version of C++ making it easy to learn how to program. More importantly, there are hundreds of shields that can be coupled with the Arduino in order to instill extra functionality.
What is an Arduino shield?
An Arduino shield is a board that is coupled together with an Arduino to introduce more features and increases functionality. There are shields for all types of functionalities like Wi-Fi, power supply, LCD, LED matrix among many others. There are so many shields such that if you need to do something, there is a high chance that there exists a shield to get started. Shields are plugged right on top of the Arduino with the pins on the shield fitting snugly into the Arduino’s header.
Factors to consider when buying a shield
The Arduino board you intend to use it with
There are numerous Arduino boards and some shields may not be compatible with all Arduinos. It’s therefore prudent to ascertain that the shield you are seeking with the board that you have.
This refers to where the input/output pins are positioned and their respective function. You have to ensure that the shield you are using has the same pinout as your Arduino board. To ascertain this, you need to check the data sheet, research about the shield, physically inspect the shield or even try fitting the shield onto the Arduino’s headers.
Shield’s operating voltage
While a shield may fit well with the board, it may still be incompatible because of the voltage levels. Some Arduino boards use 3.3V, whereas another may be using 5V. If you use a shield with an Arduino of different voltage level, either the Arduino or the shield will become damaged. You should be able to obtain this information from the shields data sheet. Notably, most shields are designed with the Arduino UNO in mind, hence they operate at 5V.
The shield’s pins and the voltage may compatible but you will still have one more hurdle to jump, the libraries for your shield of choice. Many libraries do not use the Arduino library to determine I/O pin numbers and use of hardware but instead, the libraries access the hardware directly via registers unique to the AVR or ARM cores. This results in a performance boost, however, a library meant for the UNO may not work since one is an AVR core while the other is an ARM core hence they have different architectures.
Shields are readily available on many online platforms. However, it’s advisable that you first that you first download its data sheet and check it for all the above-mentioned factors before purchasing.