Construction

130 Hacking Electronics

Construction

In this project, the Arduino is powered from an external power supply rather than the USB connection to the computer. There are two reasons for this. One is that the Ethernet Shield will not operate just from USB power, and the other is that once the Arduino has been programmed—there is no need for it to be connected to your computer, so it may as well be powered from a separate adapter.

The wiring diagram for the project is shown in Figure 6-26.

Connect everything up as shown in Figure 6-26 and load the sketch “web_relay” into the Arduino IDE. Don’t upload it onto the Arduino itself just yet. There are some configuration changes we need to make first.

Figure 6-26 Wiring diagram for remote relay control