node-red-contrib-ads1x15/ads1x15/ads1x15.js

Node-Red node for ADS1015 and ADS1115 I2C ADC

module.exports = function (RED) {
    "use strict";
     var ads1x15 = require("node-ads1x15");

    // The Output Node
    function ads1x15Node(n) {
        RED.nodes.createNode(this, n);

        var node = this;

        this.chip = n.chip || 0;
        this.address = n.address || 0x48;
        this.i2c_dev = n.i2c_dev || '/dev/i2c-1';

        this.channel = n.channel || 0;
        this.samplesPerSecond = n.samplesPerSecond || '250';
        this.progGainAmp = n.progGainAmp || '4096';

        var adc = new ads1x15(this.chip, this.address, this.i2c_dev);



        node.on("input", function (msg) {

            var reading = 0;
            if (!adc.busy) {
                readADC();
            } else {
                node.status({ fill: "yellow", shape: "dot", text: "Waiting" });
            }


        });

        node.on("close", function () {
            //   node.port.free();
        });

        function readADC() {
            adc.readADCSingleEnded(node.channel, node.progGainAmp, node.samplesPerSecond, function (err, data) {
                if (err) {
                    node.status({ fill: "red", shape: "dot", text: "Error" });
                }
                node.status({ fill: "green", shape: "dot", text: "Read" });
                node.send({
                    payload: data
                });
            });
        }
    }
    RED.nodes.registerType("ads1x15", ads1x15Node);
}