diff --git a/docs/accelerometer-pan-tilt.md b/docs/accelerometer-pan-tilt.md
index 6e680595e..c555c7dd0 100644
--- a/docs/accelerometer-pan-tilt.md
+++ b/docs/accelerometer-pan-tilt.md
@@ -50,7 +50,7 @@ board.on("ready", function() {
   // Center all servos
   (five.Servos()).center();
 
-  accel.on("acceleration", function(err, timestamp) {
+  accel.on("acceleration", function() {
     // console.log( "acceleration", this.axis );
 
     tilt.to(Math.abs(Math.ceil(170 * this.pitch.toFixed(2)) - 180));
diff --git a/docs/classic-controller.md b/docs/classic-controller.md
index 28a5589a3..110666aca 100644
--- a/docs/classic-controller.md
+++ b/docs/classic-controller.md
@@ -58,7 +58,7 @@ board.on("ready", function() {
   // Fired when the joystick detects a change in
   // axis position.
   //
-  nunchuk.joystick.left.on("change", function(err, event) {
+  nunchuk.joystick.left.on("change", function(event) {
     console.log(
       "Left joystick " + event.axis,
       event.target[event.axis],
@@ -66,7 +66,7 @@ board.on("ready", function() {
     );
   });
 
-  nunchuk.joystick.right.on("change", function(err, event) {
+  nunchuk.joystick.right.on("change", function(event) {
     console.log(
       "Right joystick " + event.axis,
       event.target[event.axis],
@@ -98,7 +98,7 @@ board.on("ready", function() {
 
   ["down", "up", "hold"].forEach(function(type) {
 
-    nunchuk.on(type, function(err, event) {
+    nunchuk.on(type, function(event) {
       console.log(
         event.target.which + " is " + type,
 
diff --git a/docs/ir-motion.md b/docs/ir-motion.md
index 5cdc39f34..bac3691c8 100644
--- a/docs/ir-motion.md
+++ b/docs/ir-motion.md
@@ -39,19 +39,19 @@ board.on("ready", function() {
 
   // "calibrated" occurs once, at the beginning of a session,
   motion.on("calibrated", function() {
-    console.log("calibrated");
+    console.log("calibrated", Date.now());
   });
 
   // "motionstart" events are fired when the "calibrated"
   // proximal area is disrupted, generally by some form of movement
   motion.on("motionstart", function() {
-    console.log("motionstart");
+    console.log("motionstart", Date.now());
   });
 
   // "motionend" events are fired following a "motionstart" event
   // when no movement has occurred in X ms
   motion.on("motionend", function() {
-    console.log("motionend");
+    console.log("motionend", Date.now());
   });
 });
 
diff --git a/docs/ir-reflect-array.md b/docs/ir-reflect-array.md
index c4919a474..58da06af8 100644
--- a/docs/ir-reflect-array.md
+++ b/docs/ir-reflect-array.md
@@ -29,7 +29,7 @@ five.Board().on("ready", function() {
 
   // calibrate for two seconds
   eyes.calibrateUntil(function() { return !calibrating; });
-  setTimeout(function() { calibrating = false; }, 2000); 
+  setTimeout(function() { calibrating = false; }, 2000);
 
   eyes.enable();
 
@@ -37,7 +37,7 @@ five.Board().on("ready", function() {
   //
   // Fires continuously once calibrated
   //
-  eyes.on("line", function(err, line) {
+  eyes.on("line", function(line) {
     console.log("line: ", line);
   });
 });
diff --git a/docs/ir-reflect.md b/docs/ir-reflect.md
index d68d01157..8fac04911 100644
--- a/docs/ir-reflect.md
+++ b/docs/ir-reflect.md
@@ -39,7 +39,7 @@ five.Board().on("ready", function() {
   //
   // Fires continuously, every 66ms.
   //
-  ir.on("data", function(err, timestamp) {
+  ir.on("data", function() {
     console.log("data");
   });
 });
diff --git a/docs/joystick-motor-led.md b/docs/joystick-motor-led.md
index 5798b04e8..e0a85ded7 100644
--- a/docs/joystick-motor-led.md
+++ b/docs/joystick-motor-led.md
@@ -51,7 +51,7 @@ board.on("ready", function() {
 
   // Pushing the joystick to up position should start the motor,
   // releasing it will turn the motor off.
-  joystick.on("axismove", function(err, timestamp) {
+  joystick.on("axismove", function() {
 
     if (!motor.isOn && this.axis.y > 0.51) {
       motor.start();
diff --git a/docs/motor-3-pin.md b/docs/motor-3-pin.md
index fd02ad5b5..a1e7765c2 100644
--- a/docs/motor-3-pin.md
+++ b/docs/motor-3-pin.md
@@ -40,7 +40,7 @@ board.on("ready", function() {
         pwm: 9
         dir: 8
         cdir: 11
-        
+
       Motor B
         pwm: 10
         dir: 12
@@ -51,7 +51,7 @@ board.on("ready", function() {
         pwm: 6
         dir: 5
         cdir: 7
-        
+
       Motor B
         pwm: 4
         dir: 3
@@ -75,20 +75,20 @@ board.on("ready", function() {
     motor: motor
   });
 
-  motor.on("start", function(err, timestamp) {
-    console.log("start", timestamp);
+  motor.on("start", function() {
+    console.log("start", Date.now());
   });
 
-  motor.on("stop", function(err, timestamp) {
-    console.log("automated stop on timer", timestamp);
+  motor.on("stop", function() {
+    console.log("automated stop on timer", Date.now());
   });
 
-  motor.on("brake", function(err, timestamp) {
-    console.log("automated brake on timer", timestamp);
+  motor.on("brake", function() {
+    console.log("automated brake on timer", Date.now());
   });
 
-  motor.on("forward", function(err, timestamp) {
-    console.log("forward", timestamp);
+  motor.on("forward", function() {
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -96,8 +96,8 @@ board.on("ready", function() {
     });
   });
 
-  motor.on("reverse", function(err, timestamp) {
-    console.log("reverse", timestamp);
+  motor.on("reverse", function() {
+    console.log("reverse", Date.now());
 
     // demonstrate braking after 5 seconds
     board.wait(5000, function() {
diff --git a/docs/motor-PCA9685.md b/docs/motor-PCA9685.md
index fe04d3c69..d0da3b1ef 100644
--- a/docs/motor-PCA9685.md
+++ b/docs/motor-PCA9685.md
@@ -47,7 +47,7 @@ board.on("ready", function() {
 
   // "start" events fire when the motor is started.
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
 
     // Demonstrate motor stop in 2 seconds
     board.wait(2000, function() {
@@ -57,7 +57,7 @@ board.on("ready", function() {
 
   // "stop" events fire when the motor is started.
   motor.on("stop", function() {
-    console.log("stop");
+    console.log("stop", Date.now());
   });
 
   // Motor API
diff --git a/docs/motor-brake.md b/docs/motor-brake.md
index 78c0275a3..0c173eb9a 100644
--- a/docs/motor-brake.md
+++ b/docs/motor-brake.md
@@ -61,19 +61,19 @@ board.on("ready", function() {
   });
 
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
   });
 
   motor.on("stop", function() {
-    console.log("automated stop on timer");
+    console.log("automated stop on timer", Date.now());
   });
 
   motor.on("brake", function() {
-    console.log("automated brake on timer");
+    console.log("automated brake on timer", Date.now());
   });
 
   motor.on("forward", function() {
-    console.log("forward");
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -82,7 +82,7 @@ board.on("ready", function() {
   });
 
   motor.on("reverse", function() {
-    console.log("reverse");
+    console.log("reverse", Date.now());
 
     // demonstrate stopping after 5 seconds
     board.wait(5000, function() {
diff --git a/docs/motor-current.md b/docs/motor-current.md
index 298fa6251..7d12b40d8 100644
--- a/docs/motor-current.md
+++ b/docs/motor-current.md
@@ -74,19 +74,19 @@ board.on("ready", function() {
   });
 
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
   });
 
   motor.on("stop", function() {
-    console.log("automated stop on timer");
+    console.log("automated stop on timer", Date.now());
   });
 
   motor.on("brake", function() {
-    console.log("automated brake on timer");
+    console.log("automated brake on timer", Date.now());
   });
 
   motor.on("forward", function() {
-    console.log("forward");
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -95,7 +95,7 @@ board.on("ready", function() {
   });
 
   motor.on("reverse", function() {
-    console.log("reverse");
+    console.log("reverse", Date.now());
 
     // demonstrate stopping after 5 seconds
     board.wait(5000, function() {
diff --git a/docs/motor-directional.md b/docs/motor-directional.md
index ee9ad04f2..cfa881382 100644
--- a/docs/motor-directional.md
+++ b/docs/motor-directional.md
@@ -92,15 +92,15 @@ board.on("ready", function() {
   });
 
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
   });
 
   motor.on("stop", function() {
-    console.log("automated stop on timer");
+    console.log("automated stop on timer", Date.now());
   });
 
   motor.on("forward", function() {
-    console.log("forward");
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -109,7 +109,7 @@ board.on("ready", function() {
   });
 
   motor.on("reverse", function() {
-    console.log("reverse");
+    console.log("reverse", Date.now());
 
     // demonstrate stopping after 5 seconds
     board.wait(5000, function() {
diff --git a/docs/motor-hbridge.md b/docs/motor-hbridge.md
index 08af20320..9a12bdf1a 100644
--- a/docs/motor-hbridge.md
+++ b/docs/motor-hbridge.md
@@ -65,15 +65,15 @@ board.on("ready", function() {
   });
 
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
   });
 
   motor.on("stop", function() {
-    console.log("automated stop on timer");
+    console.log("automated stop on timer", Date.now());
   });
 
   motor.on("forward", function() {
-    console.log("forward");
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -82,7 +82,7 @@ board.on("ready", function() {
   });
 
   motor.on("reverse", function() {
-    console.log("reverse");
+    console.log("reverse", Date.now());
 
     // demonstrate stopping after 5 seconds
     board.wait(5000, function() {
diff --git a/docs/motor.md b/docs/motor.md
index 304a7e633..d7ca6ee41 100644
--- a/docs/motor.md
+++ b/docs/motor.md
@@ -51,7 +51,7 @@ board.on("ready", function() {
 
   // "start" events fire when the motor is started.
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
 
     // Demonstrate motor stop in 2 seconds
     board.wait(2000, function() {
@@ -61,7 +61,7 @@ board.on("ready", function() {
 
   // "stop" events fire when the motor is stopped.
   motor.on("stop", function() {
-    console.log("stop");
+    console.log("stop", Date.now());
   });
 
   // Motor API
diff --git a/docs/navigator.md b/docs/navigator.md
index a83cd9e64..04c0409b6 100644
--- a/docs/navigator.md
+++ b/docs/navigator.md
@@ -478,7 +478,7 @@ Navigator.prototype.pivot = function(which, time) {
   // distance reading has changed since the previous reading
   //
   // TODO: Avoid false positives?
-  ping.on("data", function(err) {
+  ping.on("data", function() {
     var release = 750,
       distance = Math.abs(this.inches),
       isReverse = false,
diff --git a/docs/nunchuk.md b/docs/nunchuk.md
index 67985307c..27fa4b661 100644
--- a/docs/nunchuk.md
+++ b/docs/nunchuk.md
@@ -55,7 +55,7 @@ board.on("ready", function() {
   // Fired when the joystick detects a change in
   // axis position.
   //
-  nunchuk.joystick.on("change", function(err, event) {
+  nunchuk.joystick.on("change", function(event) {
     console.log(
       "joystick " + event.axis,
       event.target[event.axis],
@@ -68,7 +68,7 @@ board.on("ready", function() {
   // Fired when the accelerometer detects a change in
   // axis position.
   //
-  nunchuk.accelerometer.on("change", function(err, event) {
+  nunchuk.accelerometer.on("change", function(event) {
     console.log(
       "accelerometer " + event.axis,
       event.target[event.axis],
@@ -100,7 +100,7 @@ board.on("ready", function() {
 
   ["down", "up", "hold"].forEach(function(type) {
 
-    nunchuk.on(type, function(err, event) {
+    nunchuk.on(type, function(event) {
       console.log(
         event.target.which + " is " + type,
 
diff --git a/docs/ping.md b/docs/ping.md
index 9730f5723..78da84bd8 100644
--- a/docs/ping.md
+++ b/docs/ping.md
@@ -49,7 +49,6 @@ board.on("ready", function() {
   // Calculated distance to object in centimeters
   //
 
-
   ping.on("change", function() {
     console.log("Object is " + this.in + " inches away");
   });
diff --git a/docs/servo-slider.md b/docs/servo-slider.md
index e4a80b14b..60cae58c4 100644
--- a/docs/servo-slider.md
+++ b/docs/servo-slider.md
@@ -29,32 +29,18 @@ node eg/servo-slider.js
 
 
 ```javascript
-var five = require("johnny-five"),
-  board, slider, servo, scalingRange;
-
-board = new five.Board();
+var five = require("johnny-five");
+var board = new five.Board();
 
 board.on("ready", function() {
 
-  scalingRange = [0, 170];
-
-  slider = new five.Sensor({
-    pin: "A0",
-    freq: 50
-  });
-
-  servo = new five.Servo({
-    pin: 10,
-    range: scalingRange
-  });
-
-
-  // The slider's value will be scaled to match the servo's movement range
-
-  slider.scale(scalingRange).on("slide", function(err, value) {
+  var slider = new five.Sensor("A0");
+  var tilt = new five.Servo(9);
 
-    servo.to(Math.floor(this.value));
+  slider.scale([0, 180]).on("slide", function() {
 
+    // The slider's value will be scaled to match the tilt servo range
+    tilt.to(this.value);
   });
 });
 
diff --git a/docs/sonar-scan.md b/docs/sonar-scan.md
index 6dedecc7c..4074a5664 100644
--- a/docs/sonar-scan.md
+++ b/docs/sonar-scan.md
@@ -130,7 +130,7 @@ board.on("ready", function() {
   // [2] Sonar "change" events are emitted when the value of a
   // distance reading has changed since the previous reading
   //
-  sonar.on("change", function(err) {
+  sonar.on("change", function() {
     var turnTo;
 
     // Detect collision
diff --git a/docs/tinkerkit-accelerometer.md b/docs/tinkerkit-accelerometer.md
index f7cf493a6..b8600a2d0 100644
--- a/docs/tinkerkit-accelerometer.md
+++ b/docs/tinkerkit-accelerometer.md
@@ -18,10 +18,8 @@ node eg/tinkerkit-accelerometer.js
 
 
 ```javascript
-var five = require("johnny-five"),
-  board, accel;
-
-board = new five.Board();
+var five = require("johnny-five");
+var board = new five.Board();
 
 board.on("ready", function() {
 
@@ -32,7 +30,7 @@ board.on("ready", function() {
   // - Dual Axis http://tinkerkit.tihhs.nl/accelerometer/
   //
 
-  accel = new five.Accelerometer({
+  var accel = new five.Accelerometer({
     pins: ["I0", "I1"],
     freq: 100
   });
@@ -44,7 +42,7 @@ board.on("ready", function() {
   // Fires once every N ms, equal to value of freg
   // Defaults to 500ms
   //
-  accel.on("acceleration", function(err, timestamp) {
+  accel.on("acceleration", function() {
 
     console.log("acceleration", this.pitch, this.roll);
   });
@@ -53,7 +51,7 @@ board.on("ready", function() {
   //
   // Fires only when X, Y or Z has changed
   //
-  accel.on("axischange", function(err, timestamp) {
+  accel.on("axischange", function() {
 
     console.log("axischange", this.raw);
   });
diff --git a/eg/accelerometer-pan-tilt.js b/eg/accelerometer-pan-tilt.js
index 40f066262..36f79990b 100644
--- a/eg/accelerometer-pan-tilt.js
+++ b/eg/accelerometer-pan-tilt.js
@@ -30,7 +30,7 @@ board.on("ready", function() {
   // Center all servos
   (five.Servos()).center();
 
-  accel.on("acceleration", function(err, timestamp) {
+  accel.on("acceleration", function() {
     // console.log( "acceleration", this.axis );
 
     tilt.to(Math.abs(Math.ceil(170 * this.pitch.toFixed(2)) - 180));
diff --git a/eg/classic-controller.js b/eg/classic-controller.js
index 0db61ea8d..2c3a05316 100644
--- a/eg/classic-controller.js
+++ b/eg/classic-controller.js
@@ -38,7 +38,7 @@ board.on("ready", function() {
   // Fired when the joystick detects a change in
   // axis position.
   //
-  nunchuk.joystick.left.on("change", function(err, event) {
+  nunchuk.joystick.left.on("change", function(event) {
     console.log(
       "Left joystick " + event.axis,
       event.target[event.axis],
@@ -46,7 +46,7 @@ board.on("ready", function() {
     );
   });
 
-  nunchuk.joystick.right.on("change", function(err, event) {
+  nunchuk.joystick.right.on("change", function(event) {
     console.log(
       "Right joystick " + event.axis,
       event.target[event.axis],
@@ -78,7 +78,7 @@ board.on("ready", function() {
 
   ["down", "up", "hold"].forEach(function(type) {
 
-    nunchuk.on(type, function(err, event) {
+    nunchuk.on(type, function(event) {
       console.log(
         event.target.which + " is " + type,
 
diff --git a/eg/gripper.js b/eg/gripper.js
index 21922e66f..481c88670 100644
--- a/eg/gripper.js
+++ b/eg/gripper.js
@@ -52,13 +52,13 @@ var five = require("../lib/johnny-five.js"),
     // g.*() from REPL
     //
     //
-    motion.on("motionstart", function(err, ts) {
+    motion.on("motionstart", function() {
       chop();
     });
 
     // "motionstart" events are fired following a "motionstart event
     // when no movement has occurred in X ms
-    motion.on("motionend", function(err, ts) {
+    motion.on("motionend", function() {
       if (repeater) {
         repeater.stop();
         repeater = null;
diff --git a/eg/ir-motion.js b/eg/ir-motion.js
index ae51e898e..a5e8a07ff 100644
--- a/eg/ir-motion.js
+++ b/eg/ir-motion.js
@@ -8,18 +8,18 @@ board.on("ready", function() {
 
   // "calibrated" occurs once, at the beginning of a session,
   motion.on("calibrated", function() {
-    console.log("calibrated");
+    console.log("calibrated", Date.now());
   });
 
   // "motionstart" events are fired when the "calibrated"
   // proximal area is disrupted, generally by some form of movement
   motion.on("motionstart", function() {
-    console.log("motionstart");
+    console.log("motionstart", Date.now());
   });
 
   // "motionend" events are fired following a "motionstart" event
   // when no movement has occurred in X ms
   motion.on("motionend", function() {
-    console.log("motionend");
+    console.log("motionend", Date.now());
   });
 });
diff --git a/eg/ir-reflect-array.js b/eg/ir-reflect-array.js
index 609f2c353..e409ab655 100644
--- a/eg/ir-reflect-array.js
+++ b/eg/ir-reflect-array.js
@@ -9,7 +9,7 @@ five.Board().on("ready", function() {
 
   // calibrate for two seconds
   eyes.calibrateUntil(function() { return !calibrating; });
-  setTimeout(function() { calibrating = false; }, 2000); 
+  setTimeout(function() { calibrating = false; }, 2000);
 
   eyes.enable();
 
@@ -17,7 +17,7 @@ five.Board().on("ready", function() {
   //
   // Fires continuously once calibrated
   //
-  eyes.on("line", function(err, line) {
+  eyes.on("line", function(line) {
     console.log("line: ", line);
   });
 });
diff --git a/eg/ir-reflect.js b/eg/ir-reflect.js
index daca85f6e..7bbd50150 100644
--- a/eg/ir-reflect.js
+++ b/eg/ir-reflect.js
@@ -19,7 +19,7 @@ five.Board().on("ready", function() {
   //
   // Fires continuously, every 66ms.
   //
-  ir.on("data", function(err, timestamp) {
+  ir.on("data", function() {
     console.log("data");
   });
 });
diff --git a/eg/joystick-motor-led.js b/eg/joystick-motor-led.js
index 619d461cb..db0174142 100644
--- a/eg/joystick-motor-led.js
+++ b/eg/joystick-motor-led.js
@@ -37,7 +37,7 @@ board.on("ready", function() {
 
   // Pushing the joystick to up position should start the motor,
   // releasing it will turn the motor off.
-  joystick.on("axismove", function(err, timestamp) {
+  joystick.on("axismove", function() {
 
     if (!motor.isOn && this.axis.y > 0.51) {
       motor.start();
diff --git a/eg/motor-3-pin.js b/eg/motor-3-pin.js
index 5a1a90d61..d44423f17 100644
--- a/eg/motor-3-pin.js
+++ b/eg/motor-3-pin.js
@@ -9,7 +9,7 @@ board.on("ready", function() {
         pwm: 9
         dir: 8
         cdir: 11
-        
+
       Motor B
         pwm: 10
         dir: 12
@@ -20,7 +20,7 @@ board.on("ready", function() {
         pwm: 6
         dir: 5
         cdir: 7
-        
+
       Motor B
         pwm: 4
         dir: 3
@@ -44,20 +44,20 @@ board.on("ready", function() {
     motor: motor
   });
 
-  motor.on("start", function(err, timestamp) {
-    console.log("start", timestamp);
+  motor.on("start", function() {
+    console.log("start", Date.now());
   });
 
-  motor.on("stop", function(err, timestamp) {
-    console.log("automated stop on timer", timestamp);
+  motor.on("stop", function() {
+    console.log("automated stop on timer", Date.now());
   });
 
-  motor.on("brake", function(err, timestamp) {
-    console.log("automated brake on timer", timestamp);
+  motor.on("brake", function() {
+    console.log("automated brake on timer", Date.now());
   });
 
-  motor.on("forward", function(err, timestamp) {
-    console.log("forward", timestamp);
+  motor.on("forward", function() {
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -65,8 +65,8 @@ board.on("ready", function() {
     });
   });
 
-  motor.on("reverse", function(err, timestamp) {
-    console.log("reverse", timestamp);
+  motor.on("reverse", function() {
+    console.log("reverse", Date.now());
 
     // demonstrate braking after 5 seconds
     board.wait(5000, function() {
diff --git a/eg/motor-PCA9685.js b/eg/motor-PCA9685.js
index 430851338..325643347 100644
--- a/eg/motor-PCA9685.js
+++ b/eg/motor-PCA9685.js
@@ -27,7 +27,7 @@ board.on("ready", function() {
 
   // "start" events fire when the motor is started.
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
 
     // Demonstrate motor stop in 2 seconds
     board.wait(2000, function() {
@@ -37,7 +37,7 @@ board.on("ready", function() {
 
   // "stop" events fire when the motor is started.
   motor.on("stop", function() {
-    console.log("stop");
+    console.log("stop", Date.now());
   });
 
   // Motor API
diff --git a/eg/motor-brake.js b/eg/motor-brake.js
index a724cc619..540359aa1 100644
--- a/eg/motor-brake.js
+++ b/eg/motor-brake.js
@@ -30,19 +30,19 @@ board.on("ready", function() {
   });
 
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
   });
 
   motor.on("stop", function() {
-    console.log("automated stop on timer");
+    console.log("automated stop on timer", Date.now());
   });
 
   motor.on("brake", function() {
-    console.log("automated brake on timer");
+    console.log("automated brake on timer", Date.now());
   });
 
   motor.on("forward", function() {
-    console.log("forward");
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -51,7 +51,7 @@ board.on("ready", function() {
   });
 
   motor.on("reverse", function() {
-    console.log("reverse");
+    console.log("reverse", Date.now());
 
     // demonstrate stopping after 5 seconds
     board.wait(5000, function() {
diff --git a/eg/motor-current.js b/eg/motor-current.js
index 81385c20d..2529461ab 100644
--- a/eg/motor-current.js
+++ b/eg/motor-current.js
@@ -43,19 +43,19 @@ board.on("ready", function() {
   });
 
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
   });
 
   motor.on("stop", function() {
-    console.log("automated stop on timer");
+    console.log("automated stop on timer", Date.now());
   });
 
   motor.on("brake", function() {
-    console.log("automated brake on timer");
+    console.log("automated brake on timer", Date.now());
   });
 
   motor.on("forward", function() {
-    console.log("forward");
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -64,7 +64,7 @@ board.on("ready", function() {
   });
 
   motor.on("reverse", function() {
-    console.log("reverse");
+    console.log("reverse", Date.now());
 
     // demonstrate stopping after 5 seconds
     board.wait(5000, function() {
diff --git a/eg/motor-directional.js b/eg/motor-directional.js
index b5cc051c2..11ad9daf9 100644
--- a/eg/motor-directional.js
+++ b/eg/motor-directional.js
@@ -61,15 +61,15 @@ board.on("ready", function() {
   });
 
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
   });
 
   motor.on("stop", function() {
-    console.log("automated stop on timer");
+    console.log("automated stop on timer", Date.now());
   });
 
   motor.on("forward", function() {
-    console.log("forward");
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -78,7 +78,7 @@ board.on("ready", function() {
   });
 
   motor.on("reverse", function() {
-    console.log("reverse");
+    console.log("reverse", Date.now());
 
     // demonstrate stopping after 5 seconds
     board.wait(5000, function() {
diff --git a/eg/motor-hbridge.js b/eg/motor-hbridge.js
index 92ed27d36..f5decdb1c 100644
--- a/eg/motor-hbridge.js
+++ b/eg/motor-hbridge.js
@@ -34,15 +34,15 @@ board.on("ready", function() {
   });
 
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
   });
 
   motor.on("stop", function() {
-    console.log("automated stop on timer");
+    console.log("automated stop on timer", Date.now());
   });
 
   motor.on("forward", function() {
-    console.log("forward");
+    console.log("forward", Date.now());
 
     // demonstrate switching to reverse after 5 seconds
     board.wait(5000, function() {
@@ -51,7 +51,7 @@ board.on("ready", function() {
   });
 
   motor.on("reverse", function() {
-    console.log("reverse");
+    console.log("reverse", Date.now());
 
     // demonstrate stopping after 5 seconds
     board.wait(5000, function() {
diff --git a/eg/motor.js b/eg/motor.js
index 7c5c616e2..d3487db56 100644
--- a/eg/motor.js
+++ b/eg/motor.js
@@ -20,7 +20,7 @@ board.on("ready", function() {
 
   // "start" events fire when the motor is started.
   motor.on("start", function() {
-    console.log("start");
+    console.log("start", Date.now());
 
     // Demonstrate motor stop in 2 seconds
     board.wait(2000, function() {
@@ -30,7 +30,7 @@ board.on("ready", function() {
 
   // "stop" events fire when the motor is stopped.
   motor.on("stop", function() {
-    console.log("stop");
+    console.log("stop", Date.now());
   });
 
   // Motor API
diff --git a/eg/navigator-original.js b/eg/navigator-original.js
index 8b05e995a..a17ae2d6b 100644
--- a/eg/navigator-original.js
+++ b/eg/navigator-original.js
@@ -398,7 +398,7 @@ board.on("ready", function() {
   // [2] Sonar "change" events are emitted when the value of a
   // distance reading has changed since the previous reading
   //
-  sonar.on("change", function(err) {
+  sonar.on("change", function() {
     var turnTo;
 
     // Detect collideAt
diff --git a/eg/navigator.js b/eg/navigator.js
index d2fb0bc73..f09838064 100644
--- a/eg/navigator.js
+++ b/eg/navigator.js
@@ -458,7 +458,7 @@ Navigator.prototype.pivot = function(which, time) {
   // distance reading has changed since the previous reading
   //
   // TODO: Avoid false positives?
-  ping.on("data", function(err) {
+  ping.on("data", function() {
     var release = 750,
       distance = Math.abs(this.inches),
       isReverse = false,
diff --git a/eg/nodeconf-navigator.js b/eg/nodeconf-navigator.js
index 5c782410a..4e890e0de 100644
--- a/eg/nodeconf-navigator.js
+++ b/eg/nodeconf-navigator.js
@@ -416,7 +416,7 @@ board.on("ready", function() {
   // distance reading has changed since the previous reading
   //
   // TODO: Avoid false positives?
-  ping.on("data", function(err) {
+  ping.on("data", function() {
     var release = 750,
       distance = Math.abs(this.inches),
       isReverse = false,
diff --git a/eg/nodeconf-radar.js b/eg/nodeconf-radar.js
index 6d34f2818..9ce36c44c 100644
--- a/eg/nodeconf-radar.js
+++ b/eg/nodeconf-radar.js
@@ -109,7 +109,7 @@ board.on("ready", function() {
 
     soi = socket;
 
-    ping.on("read", function() {
+    ping.on("data", function() {
 
       if (last !== degrees) {
         io.sockets.emit("ping", {
diff --git a/eg/nodeconf-slider.js b/eg/nodeconf-slider.js
index 4f5c73501..6875a2b76 100644
--- a/eg/nodeconf-slider.js
+++ b/eg/nodeconf-slider.js
@@ -1,21 +1,10 @@
-var five = require("../lib/johnny-five.js"),
-  board, slider, servo, scalingRange;
-
-board = new five.Board();
+var five = require("../lib/johnny-five.js");
+var board = new five.Board();
 
 board.on("ready", function() {
+  var slider = new five.Sensor("A0");
 
-  slider = new five.Sensor({
-    pin: "A0",
-    freq: 50
-  });
-
-  // log out the slider values to the console.
-  slider.on("slide", function(err, value) {
-    if (err) {
-      console.log("error: ", err);
-    } else {
-      console.log(Math.floor(this.value));
-    }
+  slider.on("slide", function(value) {
+    console.log(Math.floor(this.value));
   });
 });
diff --git a/eg/nunchuk.js b/eg/nunchuk.js
index 92c2c9cfa..3ce2f7af4 100644
--- a/eg/nunchuk.js
+++ b/eg/nunchuk.js
@@ -35,7 +35,7 @@ board.on("ready", function() {
   // Fired when the joystick detects a change in
   // axis position.
   //
-  nunchuk.joystick.on("change", function(err, event) {
+  nunchuk.joystick.on("change", function(event) {
     console.log(
       "joystick " + event.axis,
       event.target[event.axis],
@@ -48,7 +48,7 @@ board.on("ready", function() {
   // Fired when the accelerometer detects a change in
   // axis position.
   //
-  nunchuk.accelerometer.on("change", function(err, event) {
+  nunchuk.accelerometer.on("change", function(event) {
     console.log(
       "accelerometer " + event.axis,
       event.target[event.axis],
@@ -80,7 +80,7 @@ board.on("ready", function() {
 
   ["down", "up", "hold"].forEach(function(type) {
 
-    nunchuk.on(type, function(err, event) {
+    nunchuk.on(type, function(event) {
       console.log(
         event.target.which + " is " + type,
 
diff --git a/eg/ping.js b/eg/ping.js
index be3c38f9e..7d91ca413 100644
--- a/eg/ping.js
+++ b/eg/ping.js
@@ -18,7 +18,6 @@ board.on("ready", function() {
   // Calculated distance to object in centimeters
   //
 
-
   ping.on("change", function() {
     console.log("Object is " + this.in + " inches away");
   });
diff --git a/eg/servo-slider.js b/eg/servo-slider.js
index cb630b87e..468c9dfac 100644
--- a/eg/servo-slider.js
+++ b/eg/servo-slider.js
@@ -1,28 +1,14 @@
-var five = require("../lib/johnny-five.js"),
-  board, slider, servo, scalingRange;
-
-board = new five.Board();
+var five = require("../lib/johnny-five.js");
+var board = new five.Board();
 
 board.on("ready", function() {
 
-  scalingRange = [0, 170];
-
-  slider = new five.Sensor({
-    pin: "A0",
-    freq: 50
-  });
-
-  servo = new five.Servo({
-    pin: 10,
-    range: scalingRange
-  });
-
-
-  // The slider's value will be scaled to match the servo's movement range
-
-  slider.scale(scalingRange).on("slide", function(err, value) {
+  var slider = new five.Sensor("A0");
+  var tilt = new five.Servo(9);
 
-    servo.to(Math.floor(this.value));
+  slider.scale([0, 180]).on("slide", function() {
 
+    // The slider's value will be scaled to match the tilt servo range
+    tilt.to(this.value);
   });
 });
diff --git a/eg/slider-log.js b/eg/slider-log.js
new file mode 100644
index 000000000..546d2d735
--- /dev/null
+++ b/eg/slider-log.js
@@ -0,0 +1,11 @@
+var five = require("../lib/johnny-five.js");
+var board = new five.Board();
+
+board.on("ready", function() {
+
+  var slider = new five.Sensor("A0");
+
+  slider.scale(0, 100).on("slide", function() {
+    console.log(Math.floor(this.value));
+  });
+});
diff --git a/eg/slider-pan.js b/eg/slider-pan.js
new file mode 100644
index 000000000..c53da496a
--- /dev/null
+++ b/eg/slider-pan.js
@@ -0,0 +1,18 @@
+var five = require("../lib/johnny-five.js");
+var board = new five.Board();
+
+board.on("ready", function() {
+
+  var range = [0, 170];
+  var slider = new five.Sensor("A0");
+  var tilt = new five.Servo({
+    pin: 10,
+    range: range
+  });
+
+  slider.scale(range).on("slide", function() {
+
+    // The slider's value will be scaled to match the tilt servo range
+    tilt.to(this.value);
+  });
+});
diff --git a/eg/sonar-scan.js b/eg/sonar-scan.js
index ca1ce69e2..0cf4ff4bf 100644
--- a/eg/sonar-scan.js
+++ b/eg/sonar-scan.js
@@ -110,7 +110,7 @@ board.on("ready", function() {
   // [2] Sonar "change" events are emitted when the value of a
   // distance reading has changed since the previous reading
   //
-  sonar.on("change", function(err) {
+  sonar.on("change", function() {
     var turnTo;
 
     // Detect collision
diff --git a/eg/tinkerkit-accelerometer.js b/eg/tinkerkit-accelerometer.js
index f99d8dbd6..dae79d774 100644
--- a/eg/tinkerkit-accelerometer.js
+++ b/eg/tinkerkit-accelerometer.js
@@ -1,7 +1,5 @@
-var five = require("../lib/johnny-five.js"),
-  board, accel;
-
-board = new five.Board();
+var five = require("../lib/johnny-five.js");
+var board = new five.Board();
 
 board.on("ready", function() {
 
@@ -12,7 +10,7 @@ board.on("ready", function() {
   // - Dual Axis http://tinkerkit.tihhs.nl/accelerometer/
   //
 
-  accel = new five.Accelerometer({
+  var accel = new five.Accelerometer({
     pins: ["I0", "I1"],
     freq: 100
   });
@@ -24,7 +22,7 @@ board.on("ready", function() {
   // Fires once every N ms, equal to value of freg
   // Defaults to 500ms
   //
-  accel.on("acceleration", function(err, timestamp) {
+  accel.on("acceleration", function() {
 
     console.log("acceleration", this.pitch, this.roll);
   });
@@ -33,7 +31,7 @@ board.on("ready", function() {
   //
   // Fires only when X, Y or Z has changed
   //
-  accel.on("axischange", function(err, timestamp) {
+  accel.on("axischange", function() {
 
     console.log("axischange", this.raw);
   });
diff --git a/lib/ir.js b/lib/ir.js
index 3ff6bc9fa..dce9bc143 100644
--- a/lib/ir.js
+++ b/lib/ir.js
@@ -28,15 +28,14 @@ Devices = {
     data: function(read, data) {
       var state = priv.get(this).state,
         value = data[0],
-        timestamp = new Date(),
-        err = null;
+        timestamp = new Date();
 
       if (value !== state && value === 1) {
-        this.emit("motionstart", err, timestamp);
+        this.emit("motionstart", timestamp);
       }
 
       if (state === 1 && value === 3) {
-        this.emit("motionend", err, timestamp);
+        this.emit("motionend", timestamp);
       }
 
       priv.set(this, {
@@ -77,11 +76,11 @@ Devices = {
       };
 
       // if ( temp.left < 200 ) {
-      //   this.emit( "left", err, timestamp );
+      //   this.emit( "left", timestamp );
       // }
 
       // if ( temp.right < 200 ) {
-      //   this.emit( "right", err, timestamp );
+      //   this.emit( "right", timestamp );
       // }
 
 
diff --git a/lib/motor.js b/lib/motor.js
index 840b5809f..d5da7b526 100644
--- a/lib/motor.js
+++ b/lib/motor.js
@@ -315,6 +315,7 @@ var Devices = {
           saveSpeed: false,
           braking: true
         });
+
         process.nextTick(this.emit.bind(this, "brake"));
 
         if (duration) {
diff --git a/lib/ping.js b/lib/ping.js
index 13a998d77..a1fea4694 100644
--- a/lib/ping.js
+++ b/lib/ping.js
@@ -49,29 +49,18 @@ function Ping(opts) {
 
   // Interval for throttled event
   setInterval(function() {
-    var err = null;
-
     if (state.value === null) {
       return;
     }
 
-    // median = samples.sort()[samples.length / 2 | 0];
-
-    // if (!median) {
-    //   median = last;
-    // }
-
-    // @DEPRECATE
-    this.emit("read", err, state.value);
-
     // The "read" event has been deprecated in
     // favor of a "data" event.
-    this.emit("data", err, state.value);
+    this.emit("data", state.value);
 
     // If the state.value for this interval is not the same as the
     // state.value in the last interval, fire a "change" event.
     if (state.value !== last) {
-      this.emit("change", err, state.value);
+      this.emit("change", state.value);
     }
 
     // Store state.value for comparison in next interval
diff --git a/lib/pir.js b/lib/pir.js
index c274f1ed9..ff37bce2c 100644
--- a/lib/pir.js
+++ b/lib/pir.js
@@ -30,8 +30,7 @@ function Pir(opts) {
   // Analog Read event loop
   // TODO: make this "throttle-able"
   this.io.digitalRead(this.pin, function(data) {
-    var timestamp = Date.now(),
-      err = null;
+    var timestamp = Date.now();
 
     // If this is not a calibration event
     if (this.value != null && this.value !== +data) {
@@ -42,13 +41,13 @@ function Pir(opts) {
       // "motionstart" event fired when motion occurs
       // within the observable range of the PIR sensor
       if (data) {
-        this.emit("motionstart", err, timestamp);
+        this.emit("motionstart", timestamp);
       }
 
       // "motionend" event fired when motion has ceased
       // within the observable range of the PIR sensor
       if (!data) {
-        this.emit("motionend", err, timestamp);
+        this.emit("motionend", timestamp);
       }
     }
 
@@ -57,12 +56,12 @@ function Pir(opts) {
     if (!this.isCalibrated) {
       this.isCalibrated = true;
       this.value = +data;
-      this.emit("calibrated", err, timestamp);
+      this.emit("calibrated", timestamp);
     }
   }.bind(this));
 
   setInterval(function() {
-    this.emit("data", null, Date.now());
+    this.emit("data", Date.now());
   }.bind(this), this.freq);
 }
 
diff --git a/lib/reflectancearray.js b/lib/reflectancearray.js
index 55b41c311..705615596 100644
--- a/lib/reflectancearray.js
+++ b/lib/reflectancearray.js
@@ -58,15 +58,15 @@ function onData(sensorState, value) {
   allRead = __.every(state.sensorStates, "dataReceived");
 
   if (allRead) {
-    this.emit("data", null, this.raw);
+    this.emit("data", this.raw);
 
     if (state.autoCalibrate) {
       setCalibration(state.calibration, this.raw);
     }
 
     if (this.isCalibrated) {
-      this.emit("calibratedData", null, this.values);
-      this.emit("line", null, this.line);
+      this.emit("calibratedData", this.values);
+      this.emit("line", this.line);
     }
 
     state.sensorStates.forEach(function(sensorState) {
@@ -244,7 +244,7 @@ ReflectanceArray.prototype.disable = function() {
 ReflectanceArray.prototype.calibrate = function() {
   var state = priv.get(this);
 
-  this.once("data", function(err, values) {
+  this.once("data", function(values) {
     setCalibration(state.calibration, values);
 
     this.emit("calibrated");
diff --git a/lib/sensor.js b/lib/sensor.js
index ff8bfe39c..d42f7e3b7 100644
--- a/lib/sensor.js
+++ b/lib/sensor.js
@@ -121,11 +121,11 @@ function Sensor(opts) {
     // For digital sensors, skip the analog
     // noise filtering provided below.
     if (opts.type === "digital") {
-      this.emit("data", err, value);
+      this.emit("data", value);
 
       if (last !== value) {
         aliases.change.forEach(function(change) {
-          this.emit(change, err, value);
+          this.emit(change, value);
         }, this);
         // Update the instance-local `last` value.
         last = value;
@@ -138,18 +138,15 @@ function Sensor(opts) {
       // Filter the accumulated sample values to reduce analog reading noise
       median = arrayMedian(samples);
     }
-    // @DEPRECATE
-    this.emit("read", err, median);
-    // The "read" event has been deprecated in
-    // favor of a "data" event.
-    this.emit("data", err, median);
+
+    this.emit("data", median);
 
     // If the filtered (median) value for this interval is at least ± the
     // configured threshold from last, fire change events
     if (median <= (last - this.threshold) || median >= (last + this.threshold)) {
       // Include all aliases
       aliases.change.forEach(function(change) {
-        this.emit(change, err, median);
+        this.emit(change, median);
       }, this);
       // Update the instance-local `last` value (only) when a new change event
       // has been emitted.  For comparison in the next interval
@@ -165,11 +162,11 @@ function Sensor(opts) {
       }
 
       if (boundary) {
-        this.emit("limit", err, {
+        this.emit("limit", {
           boundary: boundary,
           value: median
         });
-        this.emit("limit:" + boundary, err, median);
+        this.emit("limit:" + boundary, median);
       }
     }
 
diff --git a/lib/sonar.js b/lib/sonar.js
index 898480613..bc3dc27ae 100644
--- a/lib/sonar.js
+++ b/lib/sonar.js
@@ -64,8 +64,6 @@ function Sonar(opts) {
 
   // Throttle
   setInterval(function() {
-    var err = null;
-
     // Nothing read since previous interval
     if (state.samples.length === 0) {
       return;
@@ -74,19 +72,14 @@ function Sonar(opts) {
     state.median = state.samples.sort()[Math.floor(state.samples.length / 2)];
     this.value = state.median;
 
-    // @DEPRECATE
-    this.emit("read", err, state.median);
-    // The "read" event has been deprecated in
-    // favor of a "data" event.
-    this.emit("data", err, state.median);
-
+    this.emit("data", state.median);
 
     // If the state.median value for this interval is not the same as the
     // state.median value in the last interval, fire a "change" event.
     //
     if (state.last && state.median &&
       (state.median.toFixed(1) !== state.last.toFixed(1))) {
-      this.emit("change", err, state.median);
+      this.emit("change", state.median);
     }
 
     // Store this media value for comparison
diff --git a/lib/temperature.js b/lib/temperature.js
index fca55831f..2fe7427da 100644
--- a/lib/temperature.js
+++ b/lib/temperature.js
@@ -513,11 +513,11 @@ function Temperature(opts) {
     data.F = data.fahrenheit = this.fahrenheit;
     data.K = data.kelvin = this.kelvin;
 
-    this.emit("data", null, data);
+    this.emit("data", data);
 
     if (this.celsius !== last) {
       last = this.celsius;
-      this.emit("change", null, data);
+      this.emit("change", data);
     }
   }.bind(this), freq);
 }
diff --git a/lib/wii.js b/lib/wii.js
index ab00e1712..9e740d67e 100644
--- a/lib/wii.js
+++ b/lib/wii.js
@@ -124,11 +124,7 @@ function Wii(opts) {
       target: this
     });
 
-    // @DEPRECATE
-    this.emit("read", null, event);
-    // The "read" event has been deprecated in
-    // favor of a "data" event.
-    this.emit("data", null, event);
+    this.emit("data", event);
 
   }.bind(this), this.freq);
 }
diff --git a/test/reflectancearray.js b/test/reflectancearray.js
index caa4a1f9b..7ee5595b2 100644
--- a/test/reflectancearray.js
+++ b/test/reflectancearray.js
@@ -146,7 +146,7 @@ exports["ReflectanceArray"] = {
     this.sendAnalogValue(2, 77);
     this.clock.tick(25);
 
-    test.deepEqual(dataSpy.getCall(0).args[1], [55, 66, 77]);
+    test.deepEqual(dataSpy.getCall(0).args[0], [55, 66, 77]);
 
     test.done();
   },
@@ -297,7 +297,7 @@ exports["ReflectanceArray"] = {
     this.sendAnalogValue(2, testValues[2].raw);
     this.clock.tick(25);
 
-    test.deepEqual(dataSpy.getCall(0).args[1], __.pluck(testValues, "expected"));
+    test.deepEqual(dataSpy.getCall(0).args[0], __.pluck(testValues, "expected"));
 
     test.done();
   },
@@ -319,7 +319,7 @@ exports["ReflectanceArray"] = {
     this.sendAnalogValue(2, 50);
     this.clock.tick(25);
 
-    test.deepEqual(dataSpy.getCall(0).args[1], 1000);
+    test.deepEqual(dataSpy.getCall(0).args[0], 1000);
     test.equal(this.eyes.isOnLine, true);
 
     test.done();
@@ -342,7 +342,7 @@ exports["ReflectanceArray"] = {
     this.sendAnalogValue(2, 435);
     this.clock.tick(25);
 
-    test.deepEqual(dataSpy.getCall(0).args[1], 1600);
+    test.deepEqual(dataSpy.getCall(0).args[0], 1600);
     test.equal(this.eyes.isOnLine, true);
 
     test.done();
diff --git a/test/sensor.js b/test/sensor.js
index 13dd2165f..19aa530c2 100644
--- a/test/sensor.js
+++ b/test/sensor.js
@@ -216,7 +216,7 @@ exports["Sensor - Analog"] = {
       dataSpy = sinon.spy(),
       chgSpy = sinon.spy(),
       tickDelta, tickAccum, spyCall, raw, filtered;
-    test.expect(41);
+    test.expect(37);
 
     this.sensor.on("data", dataSpy);
     this.sensor.on("change", chgSpy);
@@ -270,12 +270,10 @@ exports["Sensor - Analog"] = {
     test.strictEqual(this.sensor.value, raw, "tick " + tickAccum + ": sensor value property expected to be the last value (" + raw + ") injected");
     // Check the arguments and context provided for the emitted events
     spyCall = dataSpy.getCall(0);
-    test.strictEqual(spyCall.args[0], null, "data event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor), "data event 'this' parameter expected to be source sensor object");
     spyCall = chgSpy.getCall(0);
-    test.strictEqual(spyCall.args[0], null, "change event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered, "change event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "change event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor), "change event 'this' parameter expected to be source sensor object");
 
     // Check for non-integer median value (when even number of data points and odd delta between middle two)
@@ -312,12 +310,10 @@ exports["Sensor - Analog"] = {
 
     // Check that both events provide the correct median value and context
     spyCall = dataSpy.getCall(1);
-    test.strictEqual(spyCall.args[0], null, "data event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor), "data event 'this' parameter expected to be source sensor object");
     spyCall = chgSpy.getCall(1);
-    test.strictEqual(spyCall.args[0], null, "change event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered, "change event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "change event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor), "change event 'this' parameter expected to be source sensor object");
 
     // Check that no events are emitted before the end of the next throttling interval
@@ -339,7 +335,7 @@ exports["Sensor - Analog"] = {
     test.strictEqual(this.sensor.value, raw, "sensor value property expected to be the last value (" + raw + ") read (injected)");
     // Check that the data event has the same filtered value as the previous event
     spyCall = dataSpy.getCall(2);
-    test.strictEqual(spyCall.args[1], filtered, "data event value expected to be still the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "data event value expected to be still the median (" + filtered + ") value");
 
     test.done();
   },// ./filtered: function(test)
@@ -369,7 +365,7 @@ exports["Sensor - Analog"] = {
     // elapsed (fake) time is at the end of the first (event throttling) interval
     tickAccum += tickDelta;
     test.ok(spy.calledOnce, "tick " + tickAccum + ": change event handler should have been called first time at tick " + this.defShape.freq);
-    test.strictEqual(spy.getCall(0).args[1], chgValue, "first change event value expected to be " + chgValue);
+    test.strictEqual(spy.getCall(0).args[0], chgValue, "first change event value expected to be " + chgValue);
 
     // Make sure that no change event is emitted before the end of the next throttling interval
     tickDelta = this.defShape.freq - 1;
@@ -403,7 +399,7 @@ exports["Sensor - Analog"] = {
     // elapsed time is now at the end of the third event throttling interval
     tickAccum += tickDelta;
     test.ok(spy.calledTwice, "tick " + tickAccum + ": change event handler should be called second time at tick " + (this.defShape.freq * 3));
-    test.strictEqual(spy.getCall(1).args[1], chgValue, "second change event value expected to be " + chgValue);
+    test.strictEqual(spy.getCall(1).args[0], chgValue, "second change event value expected to be " + chgValue);
 
     test.done();
   },// ./change: function(test)
@@ -413,7 +409,7 @@ exports["Sensor - Analog"] = {
     var callback = this.analogRead.args[0][1],
       spy = sinon.spy(),
       tickDelta, tickAccum, spyCall, raw, filtered, newShape;
-    test.expect(50);
+    test.expect(45);
 
     this.sensor.on("change", spy);
 
@@ -442,8 +438,7 @@ exports["Sensor - Analog"] = {
 
     // Verify the arguments and context for the call to the event handler
     spyCall = spy.getCall(0);
-    test.strictEqual(spyCall.args[0], null, "change event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered,
+    test.strictEqual(spyCall.args[0], filtered,
       "change event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor),
       "change event 'this' parameter expected to be source sensor object");
@@ -496,8 +491,7 @@ exports["Sensor - Analog"] = {
 
     // Verify the arguments and context for the call to the event handler
     spyCall = spy.getCall(1);
-    test.strictEqual(spyCall.args[0], null, "change event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered, "change event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "change event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor), "change event 'this' parameter expected to be source sensor object");
 
     // Check that no new change event is emitted when the (filtered) value changes (down) by (just) less than the threshold
@@ -582,8 +576,7 @@ exports["Sensor - Analog"] = {
 
     // Verify the arguments and context for the call to the event handler
     spyCall = spy.getCall(2);
-    test.strictEqual(spyCall.args[0], null, "change event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered, "change event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "change event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor), "change event 'this' parameter expected to be source sensor object");
 
     // Only changes of 10 or more should trigger a change event
@@ -671,8 +664,7 @@ exports["Sensor - Analog"] = {
 
     // Verify the arguments and context for the call to the event handler
     spyCall = spy.getCall(3);
-    test.strictEqual(spyCall.args[0], null, "change event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered, "change event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "change event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor), "change event 'this' parameter expected to be source sensor object");
 
     // do a new read at the end of the current interval, after the event has been emitted.
@@ -708,8 +700,7 @@ exports["Sensor - Analog"] = {
 
     // Verify the arguments and context for the call to the event handler
     spyCall = spy.getCall(4);
-    test.strictEqual(spyCall.args[0], null, "change event err argument expected to be null");
-    test.strictEqual(spyCall.args[1], filtered, "change event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(spyCall.args[0], filtered, "change event value expected to be the median (" + filtered + ") value");
     test.ok(spyCall.calledOn(this.sensor), "change event 'this' parameter expected to be source sensor object");
 
     test.done();
@@ -769,7 +760,7 @@ exports["Sensor - Analog"] = {
     tickAccum += tickDelta;
     test.strictEqual(dataSpy.callCount, 1, "tick " + tickAccum +
       ": data event handler should be called first time at tick " + this.defShape.freq);
-    test.strictEqual(dataSpy.getCall(0).args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(dataSpy.getCall(0).args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
     test.strictEqual(limitSpy.callCount + lowerSpy.callCount + upperSpy.callCount, 0,
       "tick " + tickAccum + ": no limit event handlers should be called while limit is null");
 
@@ -790,7 +781,7 @@ exports["Sensor - Analog"] = {
     tickAccum += tickDelta;
     test.strictEqual(dataSpy.callCount, 2, "tick " + tickAccum +
       ": data event handler should be called again time at tick " + this.defShape.freq * 2);
-    test.strictEqual(dataSpy.getCall(1).args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(dataSpy.getCall(1).args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
     test.strictEqual(limitSpy.callCount + lowerSpy.callCount + upperSpy.callCount, 0,
       "tick " + tickAccum + ": no limit event handlers should be called while limit is null");
 
@@ -839,7 +830,7 @@ exports["Sensor - Analog"] = {
     tickAccum += tickDelta;
     test.strictEqual(dataSpy.callCount, 3, "tick " + tickAccum +
       ": data event handler should be called every multiple of " + this.defShape.freq + " ticks");
-    test.strictEqual(dataSpy.getCall(2).args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(dataSpy.getCall(2).args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
     test.strictEqual(limitSpy.callCount + lowerSpy.callCount + upperSpy.callCount, 0,
       "tick " + tickAccum + ": no limit event handlers should be called while value is within the limits");
 
@@ -861,7 +852,7 @@ exports["Sensor - Analog"] = {
     tickAccum += tickDelta;
     test.strictEqual(dataSpy.callCount, 4, "tick " + tickAccum +
       ": data event handler should be called every multiple of " + this.defShape.freq + " ticks");
-    test.strictEqual(dataSpy.getCall(3).args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(dataSpy.getCall(3).args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
     test.strictEqual(limitSpy.callCount + lowerSpy.callCount + upperSpy.callCount, 0,
       "tick " + tickAccum + ": no limit event handlers should be called while value is within the limits");
 
@@ -881,10 +872,10 @@ exports["Sensor - Analog"] = {
       ": limit:lower event handler should be called at " + this.defShape.freq + " ticks; value at lower limit");
     test.strictEqual(upperSpy.callCount, 0, "tick " + tickAccum +
       ": limit:upper event handler should not be called at " + this.defShape.freq + " ticks; value at lower limit");
-    test.strictEqual(dataSpy.getCall(4).args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
-    test.deepEqual(limitSpy.getCall(0).args[1], { boundary: "lower", value: filtered },
+    test.strictEqual(dataSpy.getCall(4).args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.deepEqual(limitSpy.getCall(0).args[0], { boundary: "lower", value: filtered },
       "limit event value expected to be the lower boundary with the median (" + filtered + ") value");
-    test.strictEqual(lowerSpy.getCall(0).args[1], filtered, "limit:lower event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(lowerSpy.getCall(0).args[0], filtered, "limit:lower event value expected to be the median (" + filtered + ") value");
 
     // check that a value matching the upper limit emits limit and limit:upper events
     raw = 550;
@@ -902,10 +893,10 @@ exports["Sensor - Analog"] = {
       ": limit:lower event handler should not be called at " + this.defShape.freq + " ticks; value at upper limit");
     test.strictEqual(upperSpy.callCount, 1, "tick " + tickAccum +
       ": limit:upper event handler should be called at " + this.defShape.freq + " ticks; value at upper limit");
-    test.strictEqual(dataSpy.getCall(5).args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
-    test.deepEqual(limitSpy.getCall(1).args[1], { boundary: "upper", value: filtered },
+    test.strictEqual(dataSpy.getCall(5).args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.deepEqual(limitSpy.getCall(1).args[0], { boundary: "upper", value: filtered },
       "limit event value expected to be the lower boundary with the median (" + filtered + ") value");
-    test.strictEqual(upperSpy.getCall(0).args[1], filtered, "limit:upper event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(upperSpy.getCall(0).args[0], filtered, "limit:upper event value expected to be the median (" + filtered + ") value");
 
     // check that a very low value emits limit and limit:lower events
     raw = 0;
@@ -923,10 +914,10 @@ exports["Sensor - Analog"] = {
       ": limit:lower event handler should be called at " + this.defShape.freq + " ticks; value at lower limit");
     test.strictEqual(upperSpy.callCount, 1, "tick " + tickAccum +
       ": limit:upper event handler should not be called at " + this.defShape.freq + " ticks; value at lower limit");
-    test.strictEqual(dataSpy.getCall(6).args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
-    test.deepEqual(limitSpy.getCall(2).args[1], { boundary: "lower", value: filtered },
+    test.strictEqual(dataSpy.getCall(6).args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.deepEqual(limitSpy.getCall(2).args[0], { boundary: "lower", value: filtered },
       "limit event value expected to be the lower boundary with the median (" + filtered + ") value");
-    test.strictEqual(lowerSpy.getCall(1).args[1], filtered, "limit:lower event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(lowerSpy.getCall(1).args[0], filtered, "limit:lower event value expected to be the median (" + filtered + ") value");
 
     // check that a very high value emits limit and limit:upper events
     raw = 1023;
@@ -944,10 +935,10 @@ exports["Sensor - Analog"] = {
       ": limit:lower event handler should not be called at " + this.defShape.freq + " ticks; value at upper limit");
     test.strictEqual(upperSpy.callCount, 2, "tick " + tickAccum +
       ": limit:upper event handler should be called at " + this.defShape.freq + " ticks; value at upper limit");
-    test.strictEqual(dataSpy.getCall(7).args[1], filtered, "data event value expected to be the median (" + filtered + ") value");
-    test.deepEqual(limitSpy.getCall(3).args[1], { boundary: "upper", value: filtered },
+    test.strictEqual(dataSpy.getCall(7).args[0], filtered, "data event value expected to be the median (" + filtered + ") value");
+    test.deepEqual(limitSpy.getCall(3).args[0], { boundary: "upper", value: filtered },
       "limit event value expected to be the lower boundary with the median (" + filtered + ") value");
-    test.strictEqual(upperSpy.getCall(1).args[1], filtered, "limit:upper event value expected to be the median (" + filtered + ") value");
+    test.strictEqual(upperSpy.getCall(1).args[0], filtered, "limit:upper event value expected to be the median (" + filtered + ") value");
 
     test.done();
   },// ./limit: function(test)
@@ -1273,11 +1264,11 @@ exports["Sensor - Digital"] = {
     callback(0);
     this.clock.tick(25);
 
-    test.equal(data.getCall(0).args[1], 1);
-    test.equal(data.getCall(1).args[1], 0);
+    test.equal(data.getCall(0).args[0], 1);
+    test.equal(data.getCall(1).args[0], 0);
 
-    test.equal(change.getCall(0).args[1], 1);
-    test.equal(change.getCall(1).args[1], 0);
+    test.equal(change.getCall(0).args[0], 1);
+    test.equal(change.getCall(1).args[0], 0);
     test.done();
   },
 
@@ -1304,8 +1295,8 @@ exports["Sensor - Digital"] = {
     callback(0);
     this.clock.tick(25);
 
-    test.equal(spy.getCall(0).args[1], 1);
-    test.equal(spy.getCall(1).args[1], 0);
+    test.equal(spy.getCall(0).args[0], 1);
+    test.equal(spy.getCall(1).args[0], 0);
     test.done();
   },
 
diff --git a/test/temperature.js b/test/temperature.js
index 4cff17de5..15ec79b8c 100644
--- a/test/temperature.js
+++ b/test/temperature.js
@@ -99,7 +99,7 @@ function makeTestAnalogConversion(opts) {
 
     test.equal(spy.callCount, 1);
 
-    var data = spy.firstCall.args[1];
+    var data = spy.firstCall.args[0];
     test.equal(Math.round(data.C), opts.C, "data.C");
     test.equal(Math.round(data.celsius), opts.C, "data.celsius");
     test.equal(Math.round(data.K), opts.K, "data.K");
@@ -550,9 +550,9 @@ exports["Temperature -- DS18B20"] = {
 
     this.clock.tick(100);
 
-    test.equals(Math.round(spy.args[0][1].celsius), 32);
-    test.equals(Math.round(spy.args[0][1].fahrenheit), 90);
-    test.equals(Math.round(spy.args[0][1].kelvin), 305);
+    test.equals(Math.round(spy.getCall(0).args[0].celsius), 32);
+    test.equals(Math.round(spy.getCall(0).args[0].fahrenheit), 90);
+    test.equals(Math.round(spy.getCall(0).args[0].kelvin), 305);
 
     test.done();
   },
@@ -599,8 +599,8 @@ exports["Temperature -- DS18B20"] = {
 
     this.clock.tick(100);
 
-    test.equals(Math.round(spyA.args[0][1].celsius), 32);
-    test.equals(Math.round(spyB.args[0][1].celsius), 64);
+    test.equals(Math.round(spyA.getCall(0).args[0].celsius), 32);
+    test.equals(Math.round(spyB.getCall(0).args[0].celsius), 64);
 
     test.done();
   },
@@ -687,9 +687,9 @@ exports["Temperature -- MPU6050"] = {
     this.clock.tick(100);
 
     test.ok(spy.calledOnce);
-    test.equals(Math.round(spy.args[0][1].celsius), 49);
-    test.equals(Math.round(spy.args[0][1].fahrenheit), 121);
-    test.equals(Math.round(spy.args[0][1].kelvin), 323);
+    test.equals(Math.round(spy.getCall(0).args[0].celsius), 49);
+    test.equals(Math.round(spy.getCall(0).args[0].fahrenheit), 121);
+    test.equals(Math.round(spy.getCall(0).args[0].kelvin), 323);
 
     test.done();
   }
@@ -863,9 +863,9 @@ exports["Temperature -- SI7020"] = {
     this.clock.tick(10);
 
     test.ok(spy.calledOnce);
-    test.equals(Math.round(spy.args[0][1].celsius), 24);
-    test.equals(Math.round(spy.args[0][1].fahrenheit), 75);
-    test.equals(Math.round(spy.args[0][1].kelvin), 297);
+    test.equals(Math.round(spy.getCall(0).args[0].celsius), 24);
+    test.equals(Math.round(spy.getCall(0).args[0].fahrenheit), 75);
+    test.equals(Math.round(spy.getCall(0).args[0].kelvin), 297);
 
     test.done();
   }
@@ -950,9 +950,9 @@ exports["Temperature -- HTU21D"] = {
     this.clock.tick(10);
 
     test.ok(spy.calledOnce);
-    test.equals(Math.round(spy.args[0][1].celsius), 24);
-    test.equals(Math.round(spy.args[0][1].fahrenheit), 75);
-    test.equals(Math.round(spy.args[0][1].kelvin), 297);
+    test.equals(Math.round(spy.getCall(0).args[0].celsius), 24);
+    test.equals(Math.round(spy.getCall(0).args[0].fahrenheit), 75);
+    test.equals(Math.round(spy.getCall(0).args[0].kelvin), 297);
 
     test.done();
   }
@@ -1081,9 +1081,9 @@ exports["Temperature -- MPL3115A2"] = {
     this.clock.tick(10);
 
     test.ok(spy.calledOnce);
-    test.equals(Math.round(spy.args[0][1].celsius), 24);
-    test.equals(Math.round(spy.args[0][1].fahrenheit), 75);
-    test.equals(Math.round(spy.args[0][1].kelvin), 297);
+    test.equals(Math.round(spy.getCall(0).args[0].celsius), 24);
+    test.equals(Math.round(spy.getCall(0).args[0].fahrenheit), 75);
+    test.equals(Math.round(spy.getCall(0).args[0].kelvin), 297);
 
     test.done();
   },
@@ -1147,12 +1147,12 @@ exports["Temperature -- MPL3115A2"] = {
     this.clock.tick(10);
 
     test.ok(spy.calledTwice);
-    test.equals(Math.round(spy.args[0][1].celsius), 24);
-    test.equals(Math.round(spy.args[0][1].fahrenheit), 75);
-    test.equals(Math.round(spy.args[0][1].kelvin), 297);
-    test.equals(Math.round(spy.args[1][1].celsius), 40);
-    test.equals(Math.round(spy.args[1][1].fahrenheit), 104);
-    test.equals(Math.round(spy.args[1][1].kelvin), 313);
+    test.equals(Math.round(spy.getCall(0).args[0].celsius), 24);
+    test.equals(Math.round(spy.getCall(0).args[0].fahrenheit), 75);
+    test.equals(Math.round(spy.getCall(0).args[0].kelvin), 297);
+    test.equals(Math.round(spy.getCall(1).args[0].celsius), 40);
+    test.equals(Math.round(spy.getCall(1).args[0].fahrenheit), 104);
+    test.equals(Math.round(spy.getCall(1).args[0].kelvin), 313);
 
     test.done();
   }