Programming Arduino Getting Started with Sketches

int
s to hold the duration of each
flash that you are going to make. You can then use a 
for
loop to step through each of the
items in the array, making a flash of the appropriate duration.
First let’s have a look at how you are going to create an array of 
int
s containing the
durations.
You indicate that a variable contains an array by placing 
[]
after the variable name.

---

In this case, you are going to set the values for the durations at the time that you create
the array. The syntax for doing this is to use curly braces and then values each separated
by commas. Don’t forget the semicolon on the end of the line.
You can access any given element of the array using the square bracket notation. So, if
you want to get the first element of the array, you can write the following:
To illustrate this, let’s create an array and then print out all its values to the Serial
Monitor:
Upload the sketch to your board and then open the Serial Monitor. If all is well, you will
see something like 
Figure 5-1
.
This is quite neat, because if you wanted to add more durations to the array, all you
would need to do is add them to the list inside the curly braces and change “9” in the 
for
loop to the new size of the array.

---

Figure 5-1
The Serial Monitor Showing the Output of Sketch 5-01
You have to be a little careful with arrays, because the compiler will not try and stop
you from accessing elements of data that are beyond the end of the array. This is because
the array is really a pointer to an address in memory, as shown in 
Figure 5-2
.
Programs keep their data, both ordinary variables and arrays, in 
memory
. Computer
memory is arranged much more rigidly than the human kind of memory. It is easiest to
think of the memory in an Arduino as a collection of pigeonholes. When you define an
array of nine elements, for example, the next available nine pigeonholes are reserved for
its use and the variable is said to point at the first pigeonhole or 
element
of the array.
Going back to our point about access being allowed beyond the bounds of your array, if
you decided to access