Rune Langoy
4x4 Keypad easy to use library that pollis the interface width pullups
Dependents: 4x4KeyBoardExample xoxokey 4x4KeyBoardExample ProgettoCassaforte ... more
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 |
|
| 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 |
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| int | getKeyIndex () |
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return the index value representating the pressed key
|
|
Diff: keypad.cpp
- Revision:
- 1:fa689a04c361
- Parent:
- 0:1fa357ea3fcc
- Child:
- 14:d6592dac4365
--- a/keypad.cpp Sat Nov 06 14:36:22 2010 +0000
+++ b/keypad.cpp Sat Sep 19 07:51:21 2015 +0000
@@ -1,4 +1,4 @@
-/* Copyright (c) 2010 Dimiter Kentri
+/* 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
@@ -19,60 +19,54 @@
THE SOFTWARE.
*/
-/*Simple example
+/*
+ Example is available in keypad.h
-#include "mbed.h"
-#include "keypad.h"
-
-Serial pc(USBTX, USBRX);
-Keypad telepad(p13,p14,p15,p16,p17,p18,p19,p20);
-
-int main(void){
- char key;
- pc.printf("Enter codes\n\r");
- while(1){
- key = telepad.getKey();
- if(key != KEY_RELEASED){
- pc.printf("%c\n",key);
- wait(0.6);
- }
- }
-} */
+*/
#include "mbed.h"
#include "keypad.h"
using namespace mbed;
-Keypad::Keypad(PinName col1, PinName col2, PinName col3, PinName col4, PinName row1,PinName row2, PinName row3, PinName row4): _col1(col1),
- _col2(col2),_col3(col3),_col4(col4),_rows(row1,row2,row3,row4) {
-
-}
+Keypad::Keypad(PinName col0, PinName col1, PinName col2, PinName col3,
+ PinName row0,PinName row1, PinName row2, PinName row3):
+ _cols(col0,col1,col2,col3) ,_rows(row0,row1,row2,row3) { }
+
+ void Keypad::enablePullUp()
+{
+ _cols.mode(PullUp);
+}
-int Keypad::getKeyIndex(){
- for(int k=0; k<4; k++) {
- _rows = 0;
- }
- for(int i=0; i<4; i++) {
- _rows = 1 << i;
- for(int j=0; j<4;j++){
- if (_col1)
- return 1+(i*4);
- else if (_col2)
- return 2+(i*4);
- else if (_col3)
- return 3+(i*4);
- else if (_col4)
- return 4+(i*4);
- }
+bool Keypad::getKeyPressed()
+{
+ _rows = 0; // Ground all keys
+ if(_cols.read()==0xff) //Chk if key is pressed
+ return false;
+
+ return true;
+}
+
+int Keypad::getKeyIndex()
+{
+ if (!getKeyPressed())
+ return -1;
+
+ //Scan rows and cols and return switch index
+ for(int i=0; i<4; i++)
+ { _rows = ~(0x01 << i);
+ for(int j=0; j<4;j++)
+ if ( !( (_cols.read()>> j )& 0x1 ))
+ return j + (i*4);
}
return -1;
}
-char Keypad::getKey(){
-int k = getKeyIndex();
-if(k != -1)
- return keys[k-1];
- else
- return 0;
+char Keypad::getKey()
+{
+ int k = getKeyIndex();
+ if(k != -1)
+ return keys[k];
+
+ return 0;
}