diff --git a/README.md b/README.md
index 3aae7a5..08e915f 100644
--- a/README.md
+++ b/README.md
@@ -35,7 +35,7 @@ The remaining [keybrd tutorials](tutorials) show how to create custom keybrd fir
 Example complex keybrd sketch
 -----------------------------
 The keybrd_DH emulates the DataHand keyboard.
-It has 72 keys, 4 layers, a sub-layer, 2 matrices, and many features.
+It has 72 keys, 4 layers, 6 sub-layers, 2 matrices, 8 LEDs, and blinking LEDs.
 The keybrd_DH and its instantiation files contain about 800 lines of code.
 
 [mainSketch.ino](https://github.com/wolfv6/keybrd_DH/blob/master/examples/keybrd_DH/mainSketch.cpp)<br>
diff --git a/doc/CHANGELOG.md b/doc/CHANGELOG.md
index 7ff3188..ec7f41f 100644
--- a/doc/CHANGELOG.md
+++ b/doc/CHANGELOG.md
@@ -7,6 +7,10 @@ keybrd version 1.0.0 will be released when the public API is stable.
 
 ## [Unreleased][unreleased]
 
+## [0.3.1] - 2016-05-30
+### Changed
+* Rename StateLayers to LayerState
+
 ## [0.3.0] - 2016-05-09
 ### Changed
 * Restructured the project directory to conform to Arduino library manager specifications
diff --git a/doc/keybrd_library_user_guide.md b/doc/keybrd_library_user_guide.md
index 8df2b00..b9e6cf6 100644
--- a/doc/keybrd_library_user_guide.md
+++ b/doc/keybrd_library_user_guide.md
@@ -190,7 +190,7 @@ Hardware items to check:
 * 5 volts across power and ground
 * To validate keyboard hardware, modify the simple single-layer keybrd sketch from the tutorial.
 
-<!-- todo after teensy LC bb, linke to minimal keybrd sketch
+<!-- todo after teensy LC bb, link to minimal keybrd sketch
 [minimal keybrd sketch](blob/master/tutorials/keybrd_2_single-layer_annotated/keybrd_2_single-layer_annotated.ino).
  -->
 
diff --git a/doc/planned_features.md b/doc/planned_features.md
index 0997c62..a4182e6 100644
--- a/doc/planned_features.md
+++ b/doc/planned_features.md
@@ -2,7 +2,7 @@ planned_features is a view of where the keybrd project is headed.
 
 Top priority
 ============
-Add interrupts for I2C
+Redesign elements of debouncer.
 
 Med priority
 ============
@@ -12,7 +12,7 @@ Add 16x16 matrix capability (currently limited to 8x8 matrices)
 
 Low priority
 ============
-Add matrix-to-layout transform array (to decouple matrix from layout)
+Add matrix-to-layout mapping array (to decouple matrix from layout)
 
 Change tutorial sketches from teensy 2.0 and PCA9655E-D IOE to Teensy LC and MCP23018 IOE
 
diff --git a/src/LED.h b/src/LED.h
index f08e826..d62bbcd 100644
--- a/src/LED.h
+++ b/src/LED.h
@@ -3,14 +3,6 @@
 
 /* LED is an abstract base class
 Each LED object is an IC pin that is used to power an LED on and off.
-
-Connect the LED in series with the resistor:
-    Calculate current-limiting-resistor value (100 Ohms to 10k Ohms will work with 5 volts)
-        R = (Vs - Vf) / If
-        http://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-led-series-resistor
-    Connect the LED's anode (the longer lead) to the AVR output pin (+)
-    Connect the LED's cathode to ground (-)
-Never connect a LED directly from ground to power.  Doing so would destroy the LED.
 */
 class LED
 {
diff --git a/tutorials/tutorial_3a_multi-layer_keyboard.md b/tutorials/tutorial_3a_multi-layer_keyboard.md
index 21a1d7a..758ae19 100644
--- a/tutorials/tutorial_3a_multi-layer_keyboard.md
+++ b/tutorials/tutorial_3a_multi-layer_keyboard.md
@@ -17,7 +17,7 @@ When you finish this tutorial you will be able to be able to modify a multi-laye
 ## Pseudo code for simple layer scheme
 The following pseudo code has just enough detail to show how layer schemes work.
 
-**Key_Layer** objects select the active layer.
+**Key_Layer** objects are used to select an active layer.
 The "layer" variable is a layer id number.
 When a Key_Layer object is pressed, it tells LayerState to update the active layer.
 ```
@@ -40,9 +40,9 @@ class LayerState
 }
 ```
 
-**Key_Layered** objects contain multiple Key pointers, one Key pointer for each layer.
-Layer ids are used like indexes to select the appropriate key.
-When a Key_Layered object is pressed, it gets the active layer from LayerState, and then sends the key of the active layer.
+**Key_Layered** objects contain multiple elements, one element for each layer.
+Layer ids are used like indexes to send the appropriate element.
+When a Key_Layered object is pressed, it gets the active layer from LayerState, and then sends the appropriate element.
 ```
 class Key_Layered
 {