Hardware Reference
In-Depth Information
the physical world. There are plenty of sensors to choose from including
temperature, light level, sound level, acceleration, and much more.
Figure 1-1.
A few possible inputs. From left to right: an accelerometer, a
photo cell, a pressure sensor, a button, and a temperature sensor.
An
output
is how a development board like the Galileo can affect the physical
world. It can be as simple as a
light emitting diode
, or LED, which glows when
electrical current runs through it. An LED might indicate whether the device
is turned on, or if there's an error (a blinking red LED would be perfect for
that). Outputs could also be motors that drive wheels on a robot, a text dis-
play for the temperature, or a speaker that plays musical tones.
Figure 1-2
shows a few.
Figure 1-2.
A few possible outputs. From left to right: a servo motor, a light
emitting diode, and an LCD character display.
