4x4 Keypad easy to use library that pollis the interface width pullups
Dependents: 4x4KeyBoardExample xoxokey 4x4KeyBoardExample ProgettoCassaforte ... more
Fork of keypad by
Simple library for reading a 4x4 keypad width at ability to use internal pullups
Import program
00001 #include "mbed.h" 00002 #include "keypad.h" 00003 00004 Serial pc(USBTX, USBRX); 00005 00006 00007 int main() { 00008 // c0 c1 c2 c3 r0 r1 r2 r3 00009 Keypad keypad( PC_3,PC_2,PA_0,PA_1,PA_4,PB_0,PC_1,PC_0 ); 00010 00011 keypad.enablePullUp(); 00012 char key; 00013 pc.printf("Please touch a key on the keypad\n\r"); 00014 while (1) 00015 { 00016 key = keypad.getKey(); 00017 if(key != KEY_RELEASED) 00018 { 00019 pc.printf("%c\r\n",key); 00020 wait(0.6); 00021 } 00022 } 00023 }
Import library
Public Member Functions |
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Keypad (PinName col0, PinName col1, PinName col2, PinName col3, PinName row0, PinName row1, PinName row2, PinName row3) | |
Create a 4x4 (col, row) or 4x4 keypad interface
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char | getKey () |
Returns the letter of the pressed key
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bool | getKeyPressed () |
Detects if any key was pressed.
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void | enablePullUp () |
Enables internal PullUp resistors on the coloums pins.
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Protected Member Functions |
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int | getKeyIndex () |
return the index value representating the pressed key
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Diff: keypad.h
- Revision:
- 1:fa689a04c361
- Parent:
- 0:1fa357ea3fcc
- Child:
- 2:cf9e1e315e74
diff -r 1fa357ea3fcc -r fa689a04c361 keypad.h --- 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(); + }; }