Page 55 - Programming the Photon Getting Started With the Internet of Things

3

Particle Syntax

The programming language used to program the Photon is called C. In this chapter

you will learn and understand some of the basic programming terms using this language.
You can use what you will learn here and apply this to most of the firmware you will write
throughout the book. To get the best out of using your Photon, you will need to learn these
basic programming fundamentals.

What Is Programming?

It may not seem obvious to a beginner what programming actually is and what a

programming language is. When you look at the Photon’s firmware you could probably
hazard a guess as to what it is actually doing without any programming knowledge, but we
need to look a bit further into how the code goes from being lines of text to something in
real time, like turning a light-emitting diode (LED) on or off.

When you press the FLASH button on the Particle Build integrated development

environment (IDE), it then implements a chain of events that results in your firmware
being uploaded to the Photon and run. What it actually does is something called
compilation, where it takes your lines of code as text and translates them into something
called binary, which is a series of 1’s and 0’s that that the Photon’s hardware will

understand. Recall from the previous chapter that you clicked the verify button before you
actually flashed any of your code to the Photon. This attempts to precompile the C code
that you have written without actually flashing it. Verifying your code also makes sure that
what you have written makes sense in the C programming language. If you have written

some code that is not within the C programming language, then when you verify your
firmware, it will return an error. The same is true when you try compiling a firmware with
no written code at all—the error returned tells us that there is no setup or loop function in

your code. As we mentioned in the previous chapter, these two functions of code are
required and must always be present within your firmware.

Let’s add the following functions to our firmware and see if it compiles:

void setup (){
}
void loop() {

}