scan a 3x4 keypad with softaware pulldown resistors by polling it continuously.

Fork of keypad by Dimiter K

Revision:
0:1fa357ea3fcc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/keypad.h	Sat Nov 06 14:36:22 2010 +0000
@@ -0,0 +1,53 @@
+/*	 Copyright (c) 2010 Dimiter Kentri
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#ifndef KEYPAD_H
+#define KEYPAD_H
+
+#include "DigitalIn.h"
+#include "BusOut.h"
+
+
+namespace mbed{
+
+const char NO_KEY = '\0';
+#define KEY_RELEASED NO_KEY
+          
+
+       
+const int keys[16] = {'1','2','3','A',
+                      '4','5','6','B',
+                      '7','8','9','C',
+                      '*','0','#','D'};
+                      
+class Keypad{    
+    public:
+        Keypad(PinName col1, PinName col2, PinName col3, PinName col4, PinName row1,PinName row2, PinName row3, PinName row4);
+        int getKeyIndex();
+        char getKey();
+
+    protected:
+        DigitalIn _col1,_col2,_col3,_col4;    
+        BusOut _rows;
+};
+
+}
+#endif