CHAPTER 3 ■ COMMUNICATION PROTOCOLS
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■ Note For hardware and software requirements and circuit instructions, refer to the
“Arduino Uno Wireless Connectivity (WiFi)” section in Chapter 2 .
Code (Arduino)
Next you are going to write the code for connecting Arduino to the Internet using WiFi
and sending test data to a server using HTTP.
Start Arduino IDE and type the following code or download it from book’s site
and open it. All the code goes into a single source file ( *.ino ) in the same sequence as
provided here, but in order to make it easy to understand and reuse, it has been divided
into four sections.
•
External libraries
•
Internet connectivity (wireless)
•
Data publish (HTTP)
•
Standard functions
External Libraries
The first section of the code includes all external libraries required to run the code. Code
in this section is the same as Listing 2-6 .
Internet Connectivity (Wireless)
The second section of the code defines variables, constants, and functions that are going
to be used for connecting to the Internet . Use the code from Listings 2-7 , 2-8 , and 2-9
(Chapter 2 ) here.
Figure 3-1. Hyper Text Transfer Protocol (HTTP)