added support for the reprapworld keypad

Marlin/pins.h

@@ -416,9 +416,27 @@
       #define BEEPER 33	 // Beeper on AUX-4
 
       //buttons are directly attached using AUX-2
-      #define BTN_EN1 37
-      #define BTN_EN2 35
-      #define BTN_ENC 31  //the click
+      #ifdef KEYPAD
+        #define BTN_EN1 64 // encoder
+        #define BTN_EN2 59 // encoder
+        #define BTN_ENC 63 // enter button
+        #define SHIFT_OUT 40 // shift register
+        #define SHIFT_CLK 44 // shift register
+        #define SHIFT_LD 42 // shift register
+        // define register bit values, don't change it
+        #define BLEN_KEYPAD_F3 0
+        #define BLEN_KEYPAD_F2 1
+        #define BLEN_KEYPAD_F1 2
+        #define BLEN_KEYPAD_UP 3
+        #define BLEN_KEYPAD_RIGHT 4
+        #define BLEN_KEYPAD_MIDDLE 5
+        #define BLEN_KEYPAD_DOWN 6
+        #define BLEN_KEYPAD_LEFT 7
+	  #else
+        #define BTN_EN1 37
+        #define BTN_EN2 35
+        #define BTN_ENC 31  //the click
+      #endif
 
       #ifdef G3D_PANEL
         #define SDCARDDETECT 49