Add flow control switches to serialport (#579)

* Fix alignment of baud rate setting.

* Add flow control flags DTR and RTS.

* Add flags for flow control RTS and DTR.

* Add pin states for flow control flags

* Change pinstates to linestates

* Remove help text about DTR/RTS defaulting to low.

* Collect flow control setting into one single command.

* Add curly braces.

* Add more curly braces.

* Add CTS and DSR settings. Add default none option. Change settings layout for flow control.

io/serialport/25-serial.html

@@ -155,7 +155,7 @@
             <td width="110px" data-i18n="serial.label.baudrate"></td>
             <td width="70px" data-i18n="serial.label.databits"></td>
             <td width="80px" data-i18n="serial.label.parity"></td>
-            <td width="70px" data-i18n="serial.label.stopbits"></td>
+            <td data-i18n="serial.label.stopbits"></td>
         </tr><tr><td>&nbsp;</td>
         <td>
             <input type="text" id="node-config-input-serialbaud" style="width:92%">
@@ -175,12 +175,46 @@
             <option value="space" data-i18n="serial.parity.space"></option>
         </select>
         </td><td>
-        <select type="text" id="node-config-input-stopbits" style="width:90%;">
+        <select type="text" id="node-config-input-stopbits" style="width:60px;">
             <option value="2">2</option>
             <option value="1">1</option>
         </select>
         </td></tr></table>
     </div>
+    <div class="form-row">
+        <table width="100%">
+            <tr>
+                <td width="100px"></td>
+                <td width="90px">DTR</td>
+                <td width="90px">RTS</td>
+                <td width="90px">CTS</td>
+                <td>DSR</td>
+            </tr>
+            <tr>
+                <td></td>
+                <td><select type="text" id="node-config-input-dtr" style="width:80px;">
+                    <option value="none" data-i18n="serial.linestates.none"></option>
+                    <option value="high" data-i18n="serial.linestates.high"></option>
+                    <option value="low" data-i18n="serial.linestates.low"></option>
+                </select></td>
+                <td><select type="text" id="node-config-input-rts" style="width:80px;">
+                    <option value="none" data-i18n="serial.linestates.none"></option>
+                    <option value="high" data-i18n="serial.linestates.high"></option>
+                    <option value="low" data-i18n="serial.linestates.low"></option>
+                </select></td>
+                <td><select type="text" id="node-config-input-cts" style="width:80px;">
+                    <option value="none" data-i18n="serial.linestates.none"></option>
+                    <option value="high" data-i18n="serial.linestates.high"></option>
+                    <option value="low" data-i18n="serial.linestates.low"></option>
+                </select></td>
+                <td><select type="text" id="node-config-input-dsr" style="width:80px;">
+                    <option value="none" data-i18n="serial.linestates.none"></option>
+                    <option value="high" data-i18n="serial.linestates.high"></option>
+                    <option value="low" data-i18n="serial.linestates.low"></option>
+                </select></td>
+            </tr>
+        </table>
+    </div>
     <div class="form-row" style="margin-top:16px; margin-bottom:0;">
         <label><i class="fa fa-sign-in"></i> <span data-i18n="serial.label.input"></span></label>
     </div>
@@ -239,6 +273,7 @@
     <p>Provides configuration options for a serial port.</p>
     <p>The search button should return a list of available serial ports to choose from, or you
     can type in the location if known.</p>
+    <p>The DTR, RTS, CTS and DSR switches can be used to permanently pull the corresponding flow control pin high or low, e.g. in order to power devices via those pins.</p>
     <p>The node can optionally wait until it matches a pre-defined character.
         The data can then be split on a fixed character, after a timeout, or after a fixed number of characters.</p>
     <p>If using a character, it can be specified as either the character, the escaped shortcut (e.g. \n), or the hex code (e.g. 0x0d).</p>
@@ -255,6 +290,10 @@
             parity: {value:"none",required:true},
             stopbits: {value:1,required:true},
             waitfor: {value:""},
+            dtr: {value:"none"},
+            rts: {value:"none"},
+            cts: {value:"none"},
+            dsr: {value:"none"},
             newline: {value:"\\n"},
             bin: {value:"false"},
             out: {value:"char"},

io/serialport/25-serial.js

@@ -18,6 +18,10 @@ module.exports = function(RED) {
         this.databits = parseInt(n.databits) || 8;
         this.parity = n.parity || "none";
         this.stopbits = parseInt(n.stopbits) || 1;
+        this.dtr = n.dtr || "none";
+        this.rts = n.rts || "none";
+        this.cts = n.cts || "none";
+        this.dsr = n.dsr || "none";
         this.bin = n.bin || "false";
         this.out = n.out || "char";
         this.waitfor = n.waitfor || "";
@@ -179,6 +183,10 @@ module.exports = function(RED) {
                     databits = serialConfig.databits,
                     parity = serialConfig.parity,
                     stopbits = serialConfig.stopbits,
+                    dtr = serialConfig.dtr,
+                    rts = serialConfig.rts,
+                    cts = serialConfig.cts,
+                    dsr = serialConfig.dsr,
                     newline = serialConfig.newline,
                     spliton = serialConfig.out,
                     waitfor = serialConfig.waitfor,
@@ -342,6 +350,13 @@ module.exports = function(RED) {
                         obj.serial.on('open',function() {
                             olderr = "";
                             RED.log.info(RED._("serial.onopen",{port:port,baud:baud,config: databits+""+parity.charAt(0).toUpperCase()+stopbits}));
+                            // Set flow control pins if necessary. Must be set all in same command.
+                            var flags = {};
+                            if (dtr != "none") { flags.dtr = (dtr!="low"); }
+                            if (rts != "none") { flags.rts = (rts!="low"); }
+                            if (cts != "none") { flags.cts = (cts!="low"); }
+                            if (dsr != "none") { flags.dsr = (dsr!="low"); }
+                            if (dtr != "none" || rts != "none" || cts != "none" || dsr != "none") { obj.serial.set(flags); }
                             if (obj.tout) { clearTimeout(obj.tout); obj.tout = null; }
                             //obj.serial.flush();
                             obj._emitter.emit('ready');

io/serialport/locales/en-US/25-serial.json

@@ -33,6 +33,11 @@
             "odd": "Odd",
             "space": "Space"
         },
+        "linestates": {
+            "none": "",
+            "high": "High",
+            "low": "Low"
+        },
         "split": {
             "character": "on the character",
             "timeout": "after a timeout of",