Write the following code in Cloud9 and save it as ldr.js
. Run the program and check the output voltage. If the LDR is exposed to bright sunlight, you may get the output message—Looks like a bright sunny day. If this is not possible, point a torch on the LDR surface. You should see the voltage has increased. Based on voltage value, you can guess the light brightness and respond by sending an SMS/e-mail or turn on a smart bulb in case of low light condition. You can also change the intensity of bulb according to the light intensity detected. The code for ldr.js
is as follows:
var b = require('bonescript'); var loopTime = 2000; var LDR = 'P9_38'; var loopTimer = setInterval(readVoltageLoop, loopTime); function readVoltageLoop() { b.analogRead(LDR, printVoltage); } function printVoltage(pinObj) { var volt = pinObj.value * 1.8; console.log("Voltage at input pin = " + volt.toPrecision(3)); if( volt > 1.6 ) { console.log("Looks like bright sunny...