Diff: Keypad.h

Revision:

0:4bbd88022a6f

Child:

1:dd892be4b7c7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Keypad.h	Tue Apr 05 17:37:55 2016 +0000
@@ -0,0 +1,82 @@
+/* Keypad Library v1.0
+ * Copyright (c) 2016 Grant Phillips
+ * grant.phillips@nmmu.ac.za
+ *
+ * This is a modified version of Riaan Ehlers' library which was written for the 
+ * Microchip PIC18 series microcontrollers.
+ *
+ * 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 "mbed.h"
+ 
+/** Class library for a polling-based 4x4 keypad.
+ * 
+ * Example:
+ * @code
+ * #include "mbed.h"
+ * #include "Keypad.h"
+ *
+ * Keypad kpad(PE_15, PE_14, PE_13, PE_12, PE_11, PE_10, PE_9, PE_8);
+ *
+ * int main() {
+ *     char key;
+ *     int released = 1;
+ *
+ *     while(1){
+ *         key = kpad.ReadKey();                   //read the current key pressed
+ *
+ *         if(key == '\0')
+ *             released = 1;                       //set the flag when all keys are released
+ *            
+ *         if((key != '\0') && (released == 1)) {  //if a key is pressed AND previous key was released
+ *             printf("%c\n", key);            
+ *             released = 0;                       //clear the flag to indicate that key is still pressed
+ *         }
+ *     }
+ * }
+ * @endcode
+ */
+ 
+class Keypad {
+  public:
+    /** Create a Keypad object.
+    * @param col1..4 DigitalOut (or BusOut) compatible pins for keypad Column data lines
+    * @param row1..4 DigitalIn (or BusIn) compatible pins for keypad Row data lines
+    */
+    Keypad(PinName col1, PinName col2, PinName col3, PinName col4, PinName row1, PinName row2, PinName row3, PinName row4);
+    
+    /** Returns the letter of the key pressed.
+    * @param 
+    *     None
+    * @return 
+    *     The character of the key pressed.  Returns '\0' if no key is pressed.
+    */
+    char ReadKey();
+    
+ 
+  private:
+    BusOut _cols;    
+    BusIn _rows;
+};
+ 
+#endif
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