bh1750

light sensor BH1750 controlled by raspberry pi based on i2c lib

Usage

Usage with Node.JS runtime

npm install
npm test
# light value is:  20 lx

Usage with IoT.js runtime

For constrained environments:

iotjs example/index.js 
# light value is:  20.833333333333336 lx

Code

var BH1750 = require('bh1750');
var light = new BH1750({
     //options
});

light.readLight(function(err, value){
    if (err) {
        console.log("light error: " + err);
        throw err;
    } else {
        console.log("light value is: ", value, "lx");
    }
});

Options

{
    address: 0x23,
    device: '/dev/i2c-1',
    command: 0x10,
    length: 2
}

Possible commands

 // No active state
 0x00

 // Wating for measurment command
 0x01

 // Reset data register value - not accepted in POWER_DOWN mode
 0x07

 // Start measurement at 1lx resolution. Measurement time is approx 120ms.
 0x10

 // Start measurement at 0.5lx resolution. Measurement time is approx 120ms.
 0x11

 // Start measurement at 4lx resolution. Measurement time is approx 16ms.
 0x13

 // Start measurement at 1lx resolution. Measurement time is approx 120ms.
 // Device is automatically set to Power Down after measurement.
 0x20

 // Start measurement at 0.5lx resolution. Measurement time is approx 120ms.
 // Device is automatically set to Power Down after measurement.
 0x21

 // Start measurement at 1lx resolution. Measurement time is approx 120ms.
 // Device is automatically set to Power Down after measurement.
 0x23

License

(The MIT License)

Copyright (c) 2013 Christophe Hamerling <[email protected]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Resources

• https://www.npmjs.com/package/bh1750
• https://www.rohm.com/documents/11308/12926/CNA09016_sg.pdf
• http://www.mouser.com/ds/2/348/bh1750fvi-e-186247.pdf
• https://github.com/rzr/generic-sensors-lite
• https://github.com/rzr/webthing-iotjs/wiki/Sensor