diff --git a/Marlin/Configuration.h b/Marlin/Configuration.h
index 9db8dee5f4..842b060640 100644
--- a/Marlin/Configuration.h
+++ b/Marlin/Configuration.h
@@ -256,8 +256,8 @@ const bool Z_ENDSTOPS_INVERTING = true; // set to true to invert the logic of th
 #define Z_MAX_LENGTH (Z_MAX_POS - Z_MIN_POS)
 
 // The position of the homing switches
-//#define MANUAL_HOME_POSITIONS  // If defined, manualy programed locations will be used
-//#define BED_CENTER_AT_0_0  // If defined the center of the bed is defined as (0,0)
+//#define MANUAL_HOME_POSITIONS  // If defined, MANUAL_*_HOME_POS below will be used
+//#define BED_CENTER_AT_0_0  // If defined, the center of the bed is at (X=0, Y=0)
 
 //Manual homing switch locations:
 #define MANUAL_X_HOME_POS 0
diff --git a/Marlin/Configuration_adv.h b/Marlin/Configuration_adv.h
index be66d18050..b74f74ad81 100644
--- a/Marlin/Configuration_adv.h
+++ b/Marlin/Configuration_adv.h
@@ -78,7 +78,7 @@
 
 //// AUTOSET LOCATIONS OF LIMIT SWITCHES
 //// Added by ZetaPhoenix 09-15-2012
-#ifdef MANUAL_HOME_POSITION  //Use manual limit switch locations
+#ifdef MANUAL_HOME_POSITIONS  // Use manual limit switch locations
   #define X_HOME_POS MANUAL_X_HOME_POS
   #define Y_HOME_POS MANUAL_Y_HOME_POS
   #define Z_HOME_POS MANUAL_Z_HOME_POS
diff --git a/Marlin/Makefile b/Marlin/Makefile
index dee6eccbe0..930a200719 100644
--- a/Marlin/Makefile
+++ b/Marlin/Makefile
@@ -173,7 +173,11 @@ F_CPU ?= 16000000
 ifeq ($(HARDWARE_VARIANT), arduino)
 HARDWARE_SRC = $(ARDUINO_INSTALL_DIR)/hardware/arduino/cores/arduino
 else
-HARDWARE_SRC = $(HARDWARE_VARIANT)/cores/arduino
+ifeq ($(shell [ $(ARDUINO_VERSION) -ge 100 ] && echo true), true)
+HARDWARE_SRC = ../ArduinoAddons/Arduino_1.x.x/$(HARDWARE_VARIANT)/cores/arduino
+else
+HARDWARE_SRC = ../ArduinoAddons/Arduino_0.xx/$(HARDWARE_VARIANT)/cores/arduino
+endif
 endif
 
 TARGET = $(notdir $(CURDIR))
diff --git a/Marlin/pins.h b/Marlin/pins.h
index 59f86a5ac7..8e9680b725 100644
--- a/Marlin/pins.h
+++ b/Marlin/pins.h
@@ -973,19 +973,16 @@
 #define X_STEP_PIN          0
 #define X_DIR_PIN           1
 #define X_ENABLE_PIN       39
-#define X_MIN_PIN          13
 #define X_MAX_PIN          -1
 
 #define Y_STEP_PIN          2
 #define Y_DIR_PIN           3
 #define Y_ENABLE_PIN       38
-#define Y_MIN_PIN          14
 #define Y_MAX_PIN          -1
 
 #define Z_STEP_PIN          4
 #define Z_DIR_PIN           5
 #define Z_ENABLE_PIN       23
-#define Z_MIN_PIN          15
 #define Z_MAX_PIN          -1
 
 #define E0_STEP_PIN         6
@@ -997,11 +994,19 @@
 #define HEATER_2_PIN       -1
 #define HEATER_BED_PIN     20  // Bed
 #define FAN_PIN            22  // Fan
+// You may need to change FAN_PIN to 16 because Marlin isn't using fastio.h
+// for the fan and Teensyduino uses a different pin mapping.
 
-#if MOTHERBOARD == 8
+#if MOTHERBOARD == 8  // Teensylu
+  #define X_MIN_PIN          13
+  #define Y_MIN_PIN          14
+  #define Z_MIN_PIN          15
   #define TEMP_0_PIN          7  // Extruder / Analog pin numbering
   #define TEMP_BED_PIN        6  // Bed / Analog pin numbering
-#else
+#else  // Printrboard
+  #define X_MIN_PIN          35
+  #define Y_MIN_PIN           8
+  #define Z_MIN_PIN          36
   #define TEMP_0_PIN          1  // Extruder / Analog pin numbering
   #define TEMP_BED_PIN        0  // Bed / Analog pin numbering
 #endif