Hardware Reference
In-Depth Information
Solution
The HC-SR04 Ultrasonic Range Sensor (shown in
Figure 2-12
) works by sending a trigger
pulse to the
Trigger
input and then measuring the pulse width on the
Echo
output. The
width of the pulse tells you the distance.
Figure 2-12. HC-SR04 Ultrasonic range sensor
To make this recipe, you will need:
▪ Breadboard and jumper wires (see
“Prototyping Equipment”
)
▪ 10 kΩ and 20 kΩ resistors (see
“Resistors”
)
▪ HC-SR04 Ultrsonic Range Sensor (see
“Miscellaneous”
)
Wire the sensor as shown in
Figure 2-13
. Note that the HC-SR04 is a 5 V device, so the
banded
wire (running from
P9_7
on the Bone to VCC on the range finder) attaches the
HC-SR04 to the Bone's 5 V power supply.
