Rune Langoy / KeypadLib

4x4 Keypad easy to use library that pollis the interface width pullups

Dependents:   4x4KeyBoardExample xoxokey 4x4KeyBoardExample ProgettoCassaforte ... more

Fork of keypad by Dimiter K

Simple library for reading a 4x4 keypad width at ability to use internal pullups

Import program
4x4KeyBoardExample - main.cpp

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
KeypadLib - Keypad Class Reference

Public Member Functions

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
.
char getKey ()
Returns the letter of the pressed key
.
bool getKeyPressed ()
Detects if any key was pressed.
void enablePullUp ()
Enables internal PullUp resistors on the coloums pins.

Protected Member Functions

int getKeyIndex ()
return the index value representating the pressed key

keypad.cpp@21:fb28bc08ded4, 2015-09-20 (annotated)

Committer:
rlanghbv
Date:
Sun Sep 20 06:00:00 2015 +0000
Revision:
21:fb28bc08ded4
Parent:
14:d6592dac4365 
doc update

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rlanghbv 1:fa689a04c361 1 /* Copyright (c) 2015 Rune Langøy
DimiterK 0:1fa357ea3fcc 2
DimiterK 0:1fa357ea3fcc 3 Permission is hereby granted, free of charge, to any person obtaining a copy
DimiterK 0:1fa357ea3fcc 4 of this software and associated documentation files (the "Software"), to deal
DimiterK 0:1fa357ea3fcc 5 in the Software without restriction, including without limitation the rights
DimiterK 0:1fa357ea3fcc 6 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
DimiterK 0:1fa357ea3fcc 7 copies of the Software, and to permit persons to whom the Software is
DimiterK 0:1fa357ea3fcc 8 furnished to do so, subject to the following conditions:
DimiterK 0:1fa357ea3fcc 9
DimiterK 0:1fa357ea3fcc 10 The above copyright notice and this permission notice shall be included in
DimiterK 0:1fa357ea3fcc 11 all copies or substantial portions of the Software.
DimiterK 0:1fa357ea3fcc 12
DimiterK 0:1fa357ea3fcc 13 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
DimiterK 0:1fa357ea3fcc 14 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
DimiterK 0:1fa357ea3fcc 15 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
DimiterK 0:1fa357ea3fcc 16 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
DimiterK 0:1fa357ea3fcc 17 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
DimiterK 0:1fa357ea3fcc 18 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
DimiterK 0:1fa357ea3fcc 19 THE SOFTWARE.
DimiterK 0:1fa357ea3fcc 20 */
DimiterK 0:1fa357ea3fcc 21
rlanghbv 1:fa689a04c361 22 /*
rlanghbv 1:fa689a04c361 23 Example is available in keypad.h
DimiterK 0:1fa357ea3fcc 24
rlanghbv 1:fa689a04c361 25 */
DimiterK 0:1fa357ea3fcc 26
DimiterK 0:1fa357ea3fcc 27 #include "mbed.h"
DimiterK 0:1fa357ea3fcc 28 #include "keypad.h"
DimiterK 0:1fa357ea3fcc 29
DimiterK 0:1fa357ea3fcc 30 using namespace mbed;
DimiterK 0:1fa357ea3fcc 31
rlanghbv 14:d6592dac4365 32 Keypad::Keypad(PinName col0, PinName col1, PinName col2, PinName col3,
rlanghbv 14:d6592dac4365 33 PinName row0,PinName row1, PinName row2, PinName row3):
rlanghbv 14:d6592dac4365 34 _cols(col0,col1,col2,col3) ,_rows(row0,row1,row2,row3) { }
rlanghbv 1:fa689a04c361 35
rlanghbv 14:d6592dac4365 36 void Keypad::enablePullUp()
rlanghbv 1:fa689a04c361 37 {
rlanghbv 14:d6592dac4365 38 _cols.mode(PullUp);
rlanghbv 1:fa689a04c361 39 }
DimiterK 0:1fa357ea3fcc 40
rlanghbv 1:fa689a04c361 41 bool Keypad::getKeyPressed()
rlanghbv 1:fa689a04c361 42 {
rlanghbv 14:d6592dac4365 43 _rows = 0; // Ground all keys
rlanghbv 1:fa689a04c361 44 if(_cols.read()==0xff) //Chk if key is pressed
rlanghbv 14:d6592dac4365 45 return false;
rlanghbv 14:d6592dac4365 46
rlanghbv 14:d6592dac4365 47 return true;
rlanghbv 1:fa689a04c361 48 }
rlanghbv 1:fa689a04c361 49
rlanghbv 1:fa689a04c361 50 int Keypad::getKeyIndex()
rlanghbv 1:fa689a04c361 51 {
rlanghbv 1:fa689a04c361 52 if (!getKeyPressed())
rlanghbv 14:d6592dac4365 53 return -1;
rlanghbv 14:d6592dac4365 54
rlanghbv 14:d6592dac4365 55 //Scan rows and cols and return switch index
rlanghbv 14:d6592dac4365 56 for(int i=0; i<4; i++) {
rlanghbv 14:d6592dac4365 57 _rows = ~(0x01 << i);
rlanghbv 14:d6592dac4365 58 for(int j=0; j<4; j++)
rlanghbv 14:d6592dac4365 59 if ( !( (_cols.read()>> j )& 0x1 ))
rlanghbv 14:d6592dac4365 60 return j + (i*4);
rlanghbv 14:d6592dac4365 61 }
DimiterK 0:1fa357ea3fcc 62 return -1;
rlanghbv 14:d6592dac4365 63 }
DimiterK 0:1fa357ea3fcc 64
rlanghbv 1:fa689a04c361 65 char Keypad::getKey()
rlanghbv 1:fa689a04c361 66 {
rlanghbv 14:d6592dac4365 67 int k = getKeyIndex();
rlanghbv 14:d6592dac4365 68 if(k != -1)
rlanghbv 14:d6592dac4365 69 return keys[k];
rlanghbv 14:d6592dac4365 70
rlanghbv 14:d6592dac4365 71 return 0;
DimiterK 0:1fa357ea3fcc 72 }