Basic change sensitivity settings for Sensor instances

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
voodootikigod · Dec 1, 2012 · aa5b2b2 · aa5b2b2
1 parent df3d1d0
commit aa5b2b2
Showing 1 changed file with 10 additions and 4 deletions.
diff --git a/lib/sensor.js b/lib/sensor.js
@@ -59,6 +59,7 @@ function Sensor( opts ) {
   // Servo instance properties
   this.freq = opts.freq || 25;
   this.range = opts.range || [ 0, 1023 ];
+  this.sensitivity = opts.sensitivity === undefined ? 1 : opts.sensitivity;
 
   // Analog Read event loop
   this.firmata.analogRead( this.pin, function( data ) {
@@ -83,7 +84,7 @@ function Sensor( opts ) {
 
   // Throttle
   setInterval(function() {
-    var err, median;
+    var err, median, low, high;
 
     err = null;
 
@@ -99,9 +100,14 @@ function Sensor( opts ) {
     //
     // Includes all aliases
     if ( median !== last ) {
-      aliases.change.forEach(function( change ) {
-        this.emit( change, err, median );
-      }, this );
+      low = last - this.sensitivity;
+      high = last + this.sensitivity;
+
+      if ( median < low || median > high ) {
+        aliases.change.forEach(function( change ) {
+          this.emit( change, err, median );
+        }, this );
+      }
     }
 
     // Store this media value for comparison