Hardware Reference
In-Depth Information
Arduino
Pin
Description
Digital
((PWM~)
13/2
These 11 pins can be used to either read or write digital values. If defined as an input, the value will be read as either 0 or 1 based on
the voltage level at the input. If defined as an output, the value will be set to either a 0 or 1 logic voltage level. (The actual voltage
will depend on the voltage logic level of your Arduino. Some are 5 V logic level, while others are 3.3 V logic level.)
Digital
TX->1
This pin and the RX pin next to it provide a serial interface that can be used to communicate with other devices.
Digital
RX->0
This pin and the TX pin next to it provide a serial interface that can be used to communicate with other devices.
Analog
IN A5/
A0
These pins do double duty. Normally, they would be used as A/D inputs to Arduino to read continuous voltage values and turn them
into integer values. However, they can also be used as digital I/O, very similar to the digital I/O pins.
You can power your Arduino from this pin. This can be especially useful after you have uploaded your program; you can then dis-
connect the USB port, and when you apply voltage to this pin, your Arduino will boot and run the uploaded program. You can use a
voltage value from 7 to 12 volts, so a wide variety of DC power adapters or battery configurations can be used.
Power
Vin
Power
GND
This pin is the ground connection associated with the Power Vin connection.
Power
GND
This is a ground connection normally associated with the Power 5 V and Power 3.3 V outputs.
Power 5
V
This is a voltage output set to 5 V.
Power
3.3 V
This is a voltage output set to 3.3 V.
RESET This pin will reset the processor, which will cause the program to be run from the beginning.
IOREF
This provides either a 3.3 V or 5 V reference, indicating the logic level of the board.
The Mega provides a bit more from an I/O pin perspective. The following image shows
the Arduino board:
Search WWH ::




Custom Search