Diff: keypad.h

Revision:

1:fa689a04c361

Parent:

0:1fa357ea3fcc

Child:

2:cf9e1e315e74

--- a/keypad.h	Sat Nov 06 14:36:22 2010 +0000
+++ b/keypad.h	Sat Sep 19 07:51:21 2015 +0000
@@ -1,4 +1,6 @@
-/*	 Copyright (c) 2010 Dimiter Kentri
+/*mbed simple keypad library, using polling 
+
+	 Copyright (c) 2015 Rune Langøy
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -25,28 +27,100 @@
 #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',
+   
+const char keys[16] = {'1','2','3','A',
                       '4','5','6','B',
                       '7','8','9','C',
                       '*','0','#','D'};
-                      
+ /**
+ * An simple polling-based interface to read a 4x4 keypad.
+ *
+ * The function getKey() reads  the index of the pressed key 
+ * and returns the letter of the pressed key 
+ *
+ *  This work is a derivative of the works done by:
+ *    Dimiter Kentri in 2010 https://developer.mbed.org/users/DimiterK/code/keypad/
+ *  and
+ *    Yoong Hor Meng in 2012 https://developer.mbed.org/users/yoonghm/code/keypad/
+ *
+ *Example
+ * 
+ * #include "mbed.h"
+ * #include "keypad.h"
+ *	  
+ * Serial pc(USBTX, USBRX); 
+ * Keypad keypad(D3,D4,D5,D6,D7,D8,D9,D10);
+ * // Keypad keypad( PC_3,PC_2,PA_0,PA_1,PA_4,PB_0,PC_1,PC_0 ); // Tested on  Nucleo303RE card
+ * 					
+ * int main(void)
+ * {
+ *  keypad.enablePullUp();
+ *  char key;
+ *  pc.printf("Please touch a key on the keypad\n\r");
+ *  while(1)
+ *  { 
+ *	key = keypad.getKey();	
+ * 	if(key != KEY_RELEASED)
+ *	{
+ *	   pc.printf("%c\n",key);
+ *	   wait(0.2);
+ *	 }
+ *  }
+ * }	
+ * @endcode
+
+ */
+                     
 class Keypad{    
     public:
+    /** Create a 4x4 (col, row) or 4x4 keypad interface:
+     *
+     *          | Col0 | Col1 | Col2 | Col3
+     *   -------+------+------+------+-----
+     *   Row 0  |   x  |   x  |   x  |  x
+     *   Row 1  |   x  |   x  |   x  |  x
+     *   Row 2  |   x  |   x  |   x  |  x
+     *   Row 3  |   x  |   x  |   x  |  x
+     *
+     *  @param col<0..3>     Row data lines
+     *  @param row<0..3>     Column data lines
+     */
         Keypad(PinName col1, PinName col2, PinName col3, PinName col4, PinName row1,PinName row2, PinName row3, PinName row4);
-        int getKeyIndex();
+    
+       /** User-defined function that returns the letter of the pressed key
+        *      if no walid key was pressed
+        *      the value -1 is returned
+        *          
+        *  returns char
+        */
         char getKey();
+        
+        /** User-defined function that returns true if any key is pressed 
+        *          
+        *  returns bool
+        */
+        bool getKeyPressed();
+        /** User-defined function enables PullUp resistors on the 
+        *          
+        *  returns bool
+        */
+        void enablePullUp();
 
     protected:
-        DigitalIn _col1,_col2,_col3,_col4;    
+        BusIn  _cols;    
         BusOut _rows;
+         /** User-defined function that return the index value 
+        *      representating the pressed key if no walid key was pressed
+        *      the value 0 is returned
+        *          
+        *  returns int
+        */
+        int getKeyIndex();
+       
 };
 
 }