Arduino Uno Manual page 5

The other Bluetooth header is a 12-pin male header. The TX, RX 5V and ground are hooked up to this
header. The only 12-pin Bluetooth connectors are generally associated with automobiles, so this connector
does not seem to be of much use. The pin spacing is also 2mm rather than the standard 2.54mm
Ultrasonic Rangefinder
A common robotic interface is Ultrasonic Rangefinders such as the HY-SRF05. These work by sending
out a ping of ultrasonic sound and timing how long it takes for the ping to come back. The board has a
dedicated 4-pin header to connect the sensor.
•
1 x 4 Ping Male Header (Yellow)
•
+ = 5V
•
R = Return (D8)
•
T = Trigger (D7)
•
G = Ground
Analog / Digital Sensors
A common issue when hooking sensors up to an Arduino is that many require ground/Vcc connections as
well as an analog input or digital I/O. This board brings out the A0-A5 pins to a row of headers that also
provide separate power and ground points for each A0-A5 pin. The white headers are the signal lines, the
red headers provide 5V and the black headers provide ground.
The A0-A5 pins can be used either for analog inputs or as digital I/O, so both types of sensors can be
supported.