Summary

In this chapter you have seen how easy it is to read data from an RFID card or tag and then to use that data to unlock an electric strike lock or to take another kind of action. I have seen projects where an RFID keyfob is attached to a bunch of keys. The RFID reader is in a bowl and when the user gets home they throw their keys into the bowl. The house reacts to that person coming home, e.g. setting their chosen temperature and light levels, playing their favorite music, turning a shower on, etc. When it comes to using an RFID reader, you are only limited by your own imagination.

Subjects and Concepts covered in Chapter 16

• How RFID technology works
• How to connect an ID12 RFID reader to an Arduino
• Reading serial data from an RFID reader
• Using a transistor to control a higher powered device
• Using the SoftwareSerial library
• Converting ASCII to hexadecimal values
• Using bitwise AND to ascertain if a number is odd or even
• Merging two HEX digits using bitshifts and bitwise OR to create a byte
• Creating checksums using XOR (Exclusive OR)
• Using strcmp to compare two strings