jsmodebus

2019-01-16 12:38:53 +08:00
parent 36025dac53
commit 935d418fe3
25 changed files with 2079 additions and 0 deletions
@@ -0,0 +1,91 @@
+'use strict';
+
+const Stampit  = require('stampit');
+const Put      = require('put');
+const EventBus = require('stampit-event-bus');
+
+const core = Stampit()
+    .compose(EventBus)
+    .init(function () {
+        this.log = this.options && this.options.log;
+
+        if (!this.log) {
+            this.log =  {
+                log:   () => console.log.apply(console, arguments),
+                error: () => console.error.apply(console, arguments),
+                warn:  () => console.warn.apply(console, arguments),
+                debug: () => console.log.apply(console, arguments)
+            };
+        }
+        let data = {
+            coils:    null,
+            holding:  null,
+            input:    null,
+            discrete: null,
+        };
+
+        let handler = {};
+
+        let init = () => {
+            if (!this.coils) {
+                data.coils = new Buffer(1024);
+            } else {
+                data.coils = this.coils;
+            }
+
+            if (!this.holding) {
+                data.holding = new Buffer(1024);
+            } else {
+                data.holding = this.holding;
+            }
+
+            if (!this.input) {
+                data.input = new Buffer(1024);
+            } else {
+                data.input = this.input;
+            }
+            if (!this.discrete) {
+                data.discrete = new Buffer(1024);
+            } else {
+                data.discrete = this.discrete;
+            }
+        };
+
+        this.onData = (pdu, callback) => {
+            // get fc and byteCount in advance
+            const fc          = pdu.readUInt8(0);
+            // const byteCount   = pdu.readUInt8(1);
+
+            // get the pdu handler
+            const reqHandler = handler[fc];
+
+            if (!reqHandler) {
+                // write a error/exception pkt to the
+                // socket with error code fc + 0x80 and
+                // exception code 0x01 (Illegal Function)
+
+                this.log.debug('no handler for fc', fc);
+
+                callback(Put().word8(fc + 0x80).word8(0x01).buffer());
+            } else {
+                reqHandler(pdu, response => {
+                    callback(response);
+                });
+            }
+        };
+
+        this.setRequestHandler = (fc, callback) => {
+            this.log.debug('setting request handler', fc);
+            handler[fc] = callback;
+            return this;
+        };
+
+        this.getCoils    = () => data.coils;
+        this.getInput    = () => data.input;
+        this.getHolding  = () => data.holding;
+        this.getDiscrete = () => data.discrete;
+
+        init();
+    });
+
+module.exports = core;