@redplc/node-red-rpi-ads1115/nodes/redplc-ads1115.js

Node-RED node for ads1115 16bit adc using with redPlc nodes.

/**
 * Copyright 2024 Derya Y. (iot.redplc@gmail.com).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 **/

"use strict";

module.exports = function(RED) {
    const syslib = require("./lib/syslib.js");
    const sysmodule = syslib.LoadModule("rpi_ads1115");
    const N_CH = 4;

    RED.nodes.registerType("redplc-ads1115", function(n) {
        var node = this;
        RED.nodes.createNode(node, n);

        node.port = parseInt(n.port);
        node.devadr = parseInt(n.devadr);
        node.tupdate = n.tupdate;
        node.mux = [parseInt(n.mux0), parseInt(n.mux1), parseInt(n.mux2), parseInt(n.mux3)]; 
        node.rate = [parseInt(n.rate0), parseInt(n.rate1), parseInt(n.rate2), parseInt(n.rate3)];
        node.gain = [parseInt(n.gain0), parseInt(n.gain1), parseInt(n.gain2), parseInt(n.gain3)];
        node.rawdata = [n.rawdata0, n.rawdata1, n.rawdata2, n.rawdata3];
        node.ch_enabled = [n.enabled0, n.enabled1, n.enabled2, n.enabled3];

        node.varname = "IA" + n.address;
        node.name = "ads1115 #" + node.port + "@" + (node.devadr + 0x48).toString(16).toUpperCase(); 

        node.ctxvar = new Array(N_CH).fill(0);
        node.onwork = false;
        node.iserror = false;
        syslib.setStatus(node, node.varname, "grey");

        if (sysmodule === undefined)
            node.iserror = syslib.outError(node, "driver error", "driver not load, wrong os or not Raspi");
        else if (!syslib.createVariable(node, node.varname, node.ctxvar))
            node.iserror = syslib.outError(node, node.varname + " duplicate", node.varname + " duplicate");
        else if (!sysmodule.open(node.port, node.devadr))
            node.iserror = syslib.outError(node, "open error", "i2c port not open, check i2c");

        node.on("input", (msg) => {
            if (node.iserror || node.onwork || (msg.payload !== true)) {
                node.send(msg);
                return;
            }

            node.onwork = true;
            
            node.id_update = setTimeout( () => {
                sysmodule.read(node.port, node.devadr, node.mux, node.gain, node.rate, node.rawdata, node.ch_enabled, 
                (readval) => {
                    if (readval === undefined)
                        syslib.outError(node, "i2c error");
                    else {
                        syslib.setStatus(node, node.varname);
    
                        for (var i = 0; i < N_CH; i++)
                            if (node.ch_enabled[i])
                                node.ctxvar[i] = readval[i];
                    }
    
                    node.onwork = false;
                });
            }, node.tupdate);

            node.send(msg);
        });

        node.on('close', () => {
            clearTimeout(node.id_update);
            syslib.deleteVariable(node, node.varname);
            sysmodule.close(node.port, node.devadr);
        });
    });
}