adding frequency configuration to pwm output (#1206)

nodes/core/hardware/36-rpi-gpio.html

@@ -193,6 +193,10 @@
         </select>
     </div>
     <br/>
+    <div class="form-row" id="node-set-freq">
+        <label for="node-input-freq"> <span data-i18n="rpi-gpio.label.freq"></span></label>
+        <input type="text" id="node-input-freq" placeholder="100">
+    </div>
     <div class="form-row">
         <label for="node-input-name"><i class="fa fa-tag"></i> <span data-i18n="common.label.name"></span></label>
         <input type="text" id="node-input-name" data-i18n="[placeholder]common.label.name">
@@ -210,6 +214,7 @@
     <p>When using PWM mode - expects an input value of a number 0 - 100. It can be floating point.</p>
     <p>PWM mode can be used to drive a servo using input values between 10 and 20 only.
     The GPIO2 pin is best for this as it uses hardware to do the PWM.</p>
+    <p>Setting high PWM frequency might occupy more CPU than expected (default is 100Hz)</p>
     <p>Requires the RPi.GPIO python library version 0.5.10 (or better) in order to work.</p>
     <p><b>Note:</b> we are using the actual physical pin numbers on connector P1 as they are easier to locate.</p>
 </script>
@@ -224,6 +229,7 @@
             pin: { value:"",required:true,validate:RED.validators.number() },
             set: { value:"" },
             level: { value:"0" },
+            freq: {value:""},
             out: { value:"out" }
         },
         inputs:1,
@@ -297,11 +303,13 @@
                     $('#node-input-set').prop('checked', false);
                     $("#dig-tip").hide();
                     $("#pwm-tip").show();
+                    $('#node-set-freq').show();
                 }
                 else {
                     $('#node-set-tick').show();
                     $("#dig-tip").show();
                     $("#pwm-tip").hide();
+                    $('#node-set-freq').hide();
                 }
             };
             $("#node-input-out").change(function () { hidestate(); });

nodes/core/hardware/36-rpi-gpio.js

@@ -137,6 +137,7 @@ module.exports = function(RED) {
         this.pin = n.pin;
         this.set = n.set || false;
         this.level = n.level || 0;
+        this.freq = n.freq || 100;
         this.out = n.out || "out";
         var node = this;
         if (!pinsInUse.hasOwnProperty(this.pin)) {
@@ -173,7 +174,7 @@ module.exports = function(RED) {
                 node.child = spawn(gpioCommand, [node.out,node.pin,node.level]);
                 node.status({fill:"green",shape:"dot",text:node.level});
             } else {
-                node.child = spawn(gpioCommand, [node.out,node.pin]);
+                node.child = spawn(gpioCommand, [node.out,node.pin,node.freq]);
                 node.status({fill:"green",shape:"dot",text:"common.status.ok"});
             }
             node.running = true;

nodes/core/hardware/nrgpio.py

@@ -35,8 +35,13 @@ if len(sys.argv) > 2:
 
     if cmd == "pwm":
         #print "Initialised pin "+str(pin)+" to PWM"
+        try: 
+            freq = int(sys.argv[3])
+        except:
+            freq = 100
+
         GPIO.setup(pin,GPIO.OUT)
-        p = GPIO.PWM(pin, 100)
+        p = GPIO.PWM(pin, freq)
         p.start(0)
 
         while True:

nodes/core/locales/en-US/messages.json

@@ -649,7 +649,8 @@
             "pikeyboard": "Pi Keyboard",
             "left": "Left",
             "right": "Right",
-            "middle": "Middle"
+            "middle": "Middle",
+            "freq": "Frequency (Hz)"
         },
         "resistor": {
             "none": "none",
@@ -671,7 +672,7 @@
             "pin": "<b>Pins in Use</b>: ",
             "in": "Tip: Only Digital Input is supported - input must be 0 or 1.",
             "dig": "Tip: For digital output - input must be 0 or 1.",
-            "pwm": "Tip: For PWM output - input must be between 0 to 100."
+            "pwm": "Tip: For PWM output - input must be between 0 to 100; setting high frequency might occupy more CPU than expected."
         },
         "types": {
             "digout": "digital output",