Hardware Reference
In-Depth Information
Figure 3-7.
This diagram shows the components used to make an external
LED blink: the Galileo, a resistor, and an LED.
Circuits and the Flow of Electricity
Before jumping back into the code, let's take a break to explain what's going
on with the circuit you created.
Electrical current
is the flow of
electrons
through a
conductor
. It's a type of energy. The electrical current from pin 13
(when it's turned on) will move towards the ground pin through a material
that allows electrons to move through it. Materials like copper and other
metals allow electrons to move freely and are therefore considered good
conductors of electricity. That's why many wires are made with copper. The
loop that allows the electrical current to flow from the pin to ground is called
a
circuit
(see
Figure 3-8
).
