@redplc/node-red-gpio/nodes/redplc-gpio-in.js

Node-RED nodes for Raspberry Pi gpio 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("./syslib.js");
    const gpiox = require("@iiot2k/gpiox");
    const NOSET = 0;

    if (gpiox === undefined)
        throw new Error("driver error @iiot2k/gpiox");

    RED.nodes.registerType("redplc-gpio-in", function(n) {
        const node = this;
        RED.nodes.createNode(node, n);

        node.varname = "I" + n.address;
        node.name = "gpio-in " + node.varname;
        node.tupdate = n.tupdate;
        node.ctxvar = new Array(28);
        node.isdi = false;
        node.iserror = false;
        node.onwork = false;
        syslib.setStatus(node, node.varname, "grey");

        if (!syslib.createVariable(node, node.varname, node.ctxvar))
            node.iserror = syslib.outError(node, node.varname + " duplicate", node.varname + " duplicate");
        else if (n.gpioinit.length == 0)
            node.iserror = syslib.setStatus(node, node.varname + " noselect", "grey");
        else {
            for (var idx = 0; idx <= 25; idx++) {
                var gpiomode; 
                
                switch(parseInt(n.gpioinit[idx])) {
                    case 1: gpiomode = gpiox.GPIO_MODE_INPUT_NOPULL; break;
                    case 2: gpiomode = gpiox.GPIO_MODE_INPUT_PULLDOWN; break;
                    case 3: gpiomode = gpiox.GPIO_MODE_INPUT_PULLUP; break;
                    default: continue;
                }

                var pin = idx + 2; // gpio pin 2..27
                node.isdi = true;
                node.ctxvar[pin] = false;

                if (!gpiox.init_gpio(pin, gpiomode, parseInt(n.gpiodeb[idx]) * 1000)) {
                    node.iserror = syslib.outError(node, " pin " + pin + " " + gpiox.error_text(), " pin " + pin + " " + gpiox.error_text());
                    break;
                }
            }

            if (!node.isdi)
                node.iserror = syslib.setStatus(node, node.varname + " noselect", "grey");
        }

        function update() {
            for (var idx = 0; idx <= 25; idx++) {
                if (n.gpioinit[idx] == NOSET) 
                    continue;
                
                var pin = idx + 2; // gpio pin 2..27
                node.ctxvar[pin] = gpiox.get_gpio(pin);
            }

            node.onwork = false;
        }

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

            node.onwork = true;
            node.id_update = setTimeout(update, node.tupdate);
            syslib.setStatus(node, node.varname);
            node.send(msg);
        });

        node.on('close', function () {
            clearTimeout(node.id_update);
            syslib.deleteVariable(node, node.varname);

            for (var idx = 0; idx <= 25; idx++)
                if (n.gpioinit[idx] != NOSET)
                    gpiox.deinit_gpio(idx + 2);
        });
    });
}