Added discrete-out node

The output node is currently in 145-digital-in. This situation is
hopefully only temporary…

hardware/BBB/145-digital-in.html

@@ -61,6 +61,14 @@
 		<label for="node-input-debounce">Debounce</label>
 		<input type="checkbox" id="node-input-debounce" style="display:inline-block; width:auto; vertical-align:top;">
 	</div>
+    <div class="form-row">
+		<label for="node-input-outputOn">Output on</label>
+	    <select type="text" id="node-input-outputOn" style="width: 200px;">
+		   <option value="both">both changes</option>
+		   <option value="rising">0 to 1 change only</option>
+		   <option value="falling">1 to 0 change only</option>
+		</select>
+	</div>
     <div class="form-row">
 		<label for="node-input-updateInterval"><i class="icon-repeat"></i> Update at</label>
 		<input id="node-input-updateInterval" type="text" style="width: 65px">
@@ -80,10 +88,10 @@
 <script type="text/x-red" data-help-name="discrete-in">
 <p>
 Discrete input for the Beaglebone Black. Sends a message with payload 0 or 1 on the
-first output each time the pin changes state, and logs the total time in the active state.
+first output when the pin changes state, and logs the total time in the active state.
 </p>
 <p>
-The node periodically sends a message with a payload of the current total active time
+The node sends a message with a payload of the current total active time
 (in seconds) on the second output at selectable intervals. An input message with topic 'load'
 and a numeric payload will set the total active time to that value: any other input message
 will reset it to zero.
@@ -92,6 +100,11 @@ will reset it to zero.
 The active state may be set to be high or low: this only affects the calculation
 of the active time, not the pin state value sent on the first output.
 </p>
+<p>
+The pin state messages may be generated for both directions of change, or for just 0 to 1
+or just 1 to 0 changes. This is useful to generate a single message from a button
+press. When using buttons or switches, enable debouncing to improve reliability.
+</p>
 </script>
 
 <!-- Register discrete-in -->
@@ -102,7 +115,8 @@ of the active time, not the pin state value sent on the first output.
         defaults: {             	// defines the editable properties of the node
 			pin: { value:"", required:true },
 			activeLow: { value:false, required:true },
-			debounce: { value:false, required: true },
+			debounce: { value:false, required:true },
+			outputOn: { value:"both", required:true },
 			updateInterval: { value:60, required:true, validate:RED.validators.number() },
             topic: { value:"" },
             name: { value:"" }
@@ -230,3 +244,111 @@ any other input message will reset it to zero.
     });
 </script>
 
+<!-- Edit dialog for discrete-out -->
+<script type="text/x-red" data-template-name="discrete-out">
+   <div class="form-row">
+	   <label for="node-input-pin"><i class="icon-asterisk"></i>Output pin</label>
+	   <select type="text" id="node-input-pin" style="width: 200px;">
+		   <option value="">select pin</option>
+		   <option value="P8_7">GPIO2_2 (P8 pin 7)</option>
+		   <option value="P8_8">GPIO2_3 (P8 pin 8)</option>
+		   <option value="P8_9">GPIO2_5 (P8 pin 9)</option>
+		   <option value="P8_10">GPIO2_4 (P8 pin 10)</option>
+		   <option value="P8_11">GPIO1_13 (P8 pin 11)</option>
+		   <option value="P8_12">GPIO1_12 (P8 pin 12)</option>
+		   <option value="P8_13">GPIO0_23 (P8 pin 13)</option>
+		   <option value="P8_14">GPIO0_26 (P8 pin 14)</option>
+		   <option value="P8_15">GPIO1_15 (P8 pin 15)</option>
+		   <option value="P8_16">GPIO1_14 (P8 pin 16)</option>
+		   <option value="P8_17">GPIO0_27 (P8 pin 17)</option>
+		   <option value="P8_18">GPIO2_1 (P8 pin 18)</option>
+		   <option value="P8_19">GPIO0_22 (P8 pin 19)</option>
+		   <option value="P8_26">GPIO1_29 (P8 pin 26)</option>
+		   <option value="P9_11">GPIO0_30 (P9 pin 11)</option>
+		   <option value="P9_12">GPIO1_28 (P9 pin 12)</option>
+		   <option value="P9_13">GPIO0_31 (P9 pin 13)</option>
+		   <option value="P9_14">GPIO1_18 (P9 pin 14)</option>
+		   <option value="P9_15">GPIO1_16 (P9 pin 15)</option>
+		   <option value="P9_16">GPIO1_19 (P9 pin 16)</option>
+		   <option value="P9_17">GPIO0_5 (P9 pin 17)</option>
+		   <option value="P9_18">GPIO0_4 (P9 pin 18)</option>
+		   <option value="P9_21">GPIO0_3 (P9 pin 21)</option>
+		   <option value="P9_22">GPIO0_2 (P9 pin 22)</option>
+		   <option value="P9_23">GPIO1_17 (P9 pin 23)</option>
+		   <option value="P9_24">GPIO0_15 (P9 pin 24)</option>
+		   <option value="P9_26">GPIO0_14 (P9 pin 26)</option>
+		   <option value="P9_27">GPIO3_19 (P9 pin 27)</option>
+		   <option value="P9_30">GPIO3_16 (P9 pin 30)</option>
+		   <option value="P9_41">GPIO0_20 (P9 pin 41)</option>
+		   <option value="P9_42">GPIO0_7 (P9 pin 42)</option>
+		   <option value="USR0">User LED 0</option>
+		   <option value="USR1">User LED 1</option>
+		   <option value="USR2">User LED 2</option>
+		   <option value="USR3">User LED 3</option>
+		</select>
+	</div>
+	<div class="form-row">
+		<label for="node-input-inverting">Inverting</label>
+		<input type="checkbox" id="node-input-inverting" style="display:inline-block; width:auto; vertical-align:top;">
+	</div>
+	<div class="form-row">
+		<label for="node-input-toggle">Toggle state</label>
+		<input type="checkbox" id="node-input-toggle" style="display:inline-block; width:auto; vertical-align:top;">
+	</div>
+    <div class="form-row">
+		<label for="node-input-defaultState">Startup as</label>
+	    <select type="text" id="node-input-defaultState" style="width: 80px;">
+		   <option value="0">0</option>
+		   <option value="1">1</option>
+		</select>
+	</div>
+    <div class="form-row">
+        <label for="node-input-name"><i class="icon-tag"></i> Name</label>
+        <input type="text" id="node-input-name" placeholder="Name">
+    </div>
+</script>
+
+<!-- Help text for discrete-out -->
+<script type="text/x-red" data-help-name="discrete-out">
+<p>
+Discrete output for the Beaglebone Black.
+</p>
+<p>
+Sets the output pin high or low depending on the payload of the input message. Numeric
+payloads > 0.5 are 'high', payloads <= 0.5 are 'low'. Other payloads which
+evaluate to true are 'high', if not then 'low'. Selecting the Inverting checkbox will
+switch the sense of the comparison.
+</p>
+<p>
+If the Toggle state checkbox is checked, any message will cause the pin to switch from
+1 to 0 and back.
+</P>
+<p>
+The pin will be initially set to the given Startup state until the first message arrives:
+the Inverting property is not applied to this value.
+</p>
+</script>
+
+<!-- Register discrete-out -->
+<script type="text/javascript">
+    RED.nodes.registerType('discrete-out', {
+        category: 'advanced-input', // the palette category
+		color:"#c6dbef",
+        defaults: {             	// defines the editable properties of the node
+			pin: { value:"", required:true },
+			inverting: { value:false, required:true },
+			toggle: { value:false, required:true },
+			defaultState: { value:"0", required:true },
+            name: { value:"" }
+        },
+        inputs:1,                	// set the number of inputs - only 0 or 1
+        outputs:0,               	// set the number of outputs - 0 to n
+        icon: "arrow-out.png",    	// set the icon (held in public/icons)
+        label: function() {      	// sets the default label contents
+            return this.name || "discrete-out: " + this.pin;
+        },
+        labelStyle: function() { 	// sets the class to apply to the label
+            return this.name ? "node_label_italic" : "";
+        }
+    });
+</script>

hardware/BBB/145-digital-in.js

@@ -37,6 +37,15 @@ function DiscreteInputNode(n) {
         this.activeState = 1;
     this.updateInterval = n.updateInterval * 1000;  // How often to send totalActiveTime messages
     this.debounce = n.debounce;                     // Enable switch contact debouncing algorithm
+    if (n.outputOn === "rising") {
+        this.activeEdges = [false, true];
+    } else if (n.outputOn === "falling") {
+        this.activeEdges = [true, false];
+    } else if (n.outputOn === "both") {
+        this.activeEdges = [true, true];
+    } else {
+        node.error("Invalid edge type: " + n.outputOn);
+    }
 
     // Working variables
     this.interruptAttached = false; // Flag: should we detach interrupt when we are closed?
@@ -93,10 +102,12 @@ function DiscreteInputNode(n) {
             } else if (!isNaN(node.lastActiveTime)) {
                 node.totalActiveTime += now - node.lastActiveTime;
             }
-            var msg = {};
+            if (node.activeEdges[node.currentState]) {
-            msg.topic = node.topic;
+                var msg = {};
-            msg.payload = node.currentState;
+                msg.topic = node.topic;
-            node.send([msg, null]);
+                msg.payload = node.currentState;
+                node.send([msg, null]);
+            }
         };
         
     // This function is called by the timer. It updates the ActiveTime variables, and sends a
@@ -131,10 +142,17 @@ function DiscreteInputNode(n) {
             if (node.currentState === node.activeState) {
                 node.lastActiveTime = Date.now();
             }
+            // On startup, send an initial activeTime message, but only send an
+            // initial currentState message if we are in both edges active mode
             if (node.starting) {
                 node.starting = false;
-                var msg = [{topic:node.topic}, {topic:node.topic}];
+                var msg;
-                msg[0].payload = node.currentState;
+                if (node.activeEdges[0] && node.activeEdges[1]) {
+                    msg = [{topic:node.topic}, {topic:node.topic}];
+                    msg[0].payload = node.currentState;
+                } else {
+                    msg = [null, {topic:node.topic}];
+                }
                 msg[1].payload = node.totalActiveTime;
                 node.send(msg);
             }
@@ -239,8 +257,8 @@ function PulseInputNode(n) {
         // Don't set up interrupts & intervals until after the close event handler has been installed
         bonescript.detachInterrupt(node.pin);
         process.nextTick(function () {
-            bonescript.pinMode(node.pin, bonescript.INPUT);
+                bonescript.pinMode(node.pin, bonescript.INPUT);
-            bonescript.digitalRead(node.pin, function (x) {
+                bonescript.digitalRead(node.pin, function (x) {
                         // Initialise the currentState based on the value read
                         node.currentState = Number(x.value);
                         // Attempt to attach an interrupt handler to the pin. If we succeed,
@@ -260,15 +278,71 @@ function PulseInputNode(n) {
                             node.error("Failed to attach interrupt");
                         }
                     });
-                });
+            });
     } else {
         node.error("Unconfigured input pin");
     }
 }
 
+// Node constructor for discrete-out
+function DiscreteOutputNode(n) {
+    RED.nodes.createNode(this, n);
+
+    // Store local copies of the node configuration (as defined in the .html)
+    this.topic = n.topic;                           // the topic is not currently used
+    this.pin = n.pin;                               // The Beaglebone Black pin identifying string
+    this.defaultState = Number(n.defaultState);     // What state to set up as
+    this.inverting = n.inverting;
+    this.toggle = n.toggle;
+    
+    // Working variables
+    this.currentState = this.defaultState;
+    
+    var node = this;
+    
+    // If the input message paylod is numeric, values > 0.5 are 'true', otherwise use
+    // the truthiness of the payload. Apply the inversion flag before setting the output
+    var inputCallback = function (msg) {
+            var newState;
+            if (node.toggle) {
+                newState = node.currentState === 0 ? 1 : 0;
+            } else {
+                if (isFinite(Number(msg.payload))) {
+                    newState = Number(msg.payload) > 0.5 ? true : false;
+                } else if (msg.payload) {
+                    newState = true;
+                } else {
+                    newState = false;
+                }
+                if (node.inverting) {
+                    newState = !newState;
+                }
+            }
+            bonescript.digitalWrite(node.pin, newState ? 1 : 0);
+            node.currentState = newState;
+        };
+    
+    // If we have a valid pin, set it as an output and set the default state
+    if (["P8_7", "P8_8", "P8_9", "P8_10", "P8_11", "P8_12", "P8_13", "P8_14", "P8_15",
+         "P8_16", "P8_17", "P8_18", "P8_19", "P8_26", "P9_11", "P9_12", "P9_13", "P9_14",
+         "P9_15", "P9_16", "P9_17", "P9_18", "P9_21", "P9_22", "P9_23", "P9_24", "P9_26",
+         "P9_27", "P9_30", "P9_41", "P9_42", "USR0", "USR1", "USR2", "USR3"].indexOf(node.pin) >= 0) {
+        // Don't set up interrupts & intervals until after the close event handler has been installed
+        bonescript.detachInterrupt(node.pin);
+        process.nextTick(function () {
+                bonescript.pinMode(node.pin, bonescript.OUTPUT);
+                node.on("input", inputCallback);
+                setTimeout(function () { bonescript.digitalWrite(node.pin, node.defaultState); }, 50);
+            });
+    } else {
+        node.error("Unconfigured output pin");
+    }
+}
+
 // Register the nodes by name. This must be called before overriding any of the Node functions.
 RED.nodes.registerType("discrete-in", DiscreteInputNode);
 RED.nodes.registerType("pulse-in", PulseInputNode);
+RED.nodes.registerType("discrete-out", DiscreteOutputNode);
 
 // On close, detach the interrupt (if we attached one) and clear any active timers
 DiscreteInputNode.prototype.close = function () {