Connecting a solar panel to Arduino

Someone asked me if it was possible to connect a solar panel to an Arduino board and then read the information in Max/MSP.

This setup was only tried with inside lighting. A different data range will be present if natural sun light is used.


Please Note
• The solar panel used in this example was rated at 2V and 25mA.
• Do not use a solar panel rated in excess of 5V. Doing so may damage the Arduino
• If data values appear incorrect, try scaling the byte 'data' in the Arduino sketch as it is captured. The analog inputs read data at 10 bit. However, a single, serially-printed value can only hold 8 bits of information.
• The data range with this particular solar panel is 0 < 6 using power-efficient, indoor lighting at night.

Hardware Connections
• USB to Arduino
• Positive terminal of solar panel (marked as red or with a plus sign) to Arduino Analog In 0
• Negative terminal of solar panel (marked as black or with a minus sign) to Arduino Ground




Arduino Code
byte data;
void setup() {
Serial.begin(57600); }
void loop() {
data = analogRead(0);
Serial.print(data);
delay(10);
}


Max/MSP Patch
Here is an example of a very simple Max/MSP patch. The value of the solar panel determines the frequency of a sinewave as being of the harmonic series with a fundamental of 100Hz.