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[quote="cak kalim"]How to read 3 key sequence (example 4,5,6) from a keypad? If the sequence is correct then the led on. Have idea, pleasetell me.[/quote]
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<table border="0" cellpadding="3" cellspacing="1" width="100%" class="forumline"> <tr> <th class="thCornerL" width="22%" height="26">Author</th> <th class="thCornerR">Message</th> </tr> <tr> <td width="22%" align="left" valign="top" class="row1"><span class="name"><a name=""></a><b>myturf</b></span></td> <td class="row1" height="28" valign="top"><table width="100%" border="0" cellspacing="0" cellpadding="0"> <tr> <td width="100%"><img src="../../forum/templates/subSilver/images/icon_minipost.gif" width="12" height="9" alt="Post" title="Post" border="0"/><span class="postdetails">Posted: Tue May 09, 2006 6:08 am<span class="gen"> </span> Post subject: Re: reading key squence from keypad</span></td> </tr> <tr> <td colspan="2"><hr/></td> </tr> <tr> <td colspan="2"><span class="postbody">Here is the source code : <br/> <br/>;PASSWORD Source code : <br/>;Using keypad to catch data and drive LED when the password is correct <br/>;For this example the password is 3 4 5 <br/>;In this lesson we'll scan keypad and get data out to LED-P0 <br/>row1 bit P2.4 <br/>row2 bit P2.5 <br/>row3 bit P2.6 <br/>row4 bit P2.7 <br/>col1 bit P2.0 <br/>col2 bit P2.1 <br/>col3 bit P2.2 <br/>col4 bit P2.3 <br/>; <br/>keydata equ 70h <br/>keybounc equ 71h <br/>keyport equ P2 <br/> org 0h <br/>pass3: call keypad4x4 ;calling subroutine keypad4x4 <br/> Mov A,keydata ;A = keydata <br/> cjne A,#3,pass3 ;detects key 3 <br/>; <br/>pass4: call keypad4x4 <br/> mov A,keydata <br/> cjne A,#4,pass4 ;detects key 4 <br/>; <br/>pass5: call keypad4x4 <br/> mov A,keydata <br/> Cjne A,#5,pass5;detects key 5 <br/>; <br/>send: CPL A ;A = NOT A <br/> Mov P0,A ;P0 = A <br/> Sjmp send ;LOOPING FOREVER PART 2 <br/>; <br/>delay: mov R0,#0 <br/>delay1:mov R2,#50 <br/> djnz R2,$ <br/> djnz R0,delay1 <br/> ret <br/>; <br/>;==================================== <br/>; subroutine scan keypad 4x4 <br/>;==================================== <br/>Keypad4x4: <br/> mov keybounc,#50 ;keybounc = 50 <br/> mov keyport,#0FFh ;keyport=P2= FF <br/> clr col1 ;col1= P3.0 = 0 <br/>Detect:jb row1,key1 ;jump to key1 if row1=1 <br/> djnz keybounc,Detect <br/> mov keydata,#00h ;Keydata =00h <br/> ret <br/>; <br/>key1: jb row2,key2 ;jump to Key2 if row2=1 <br/> djnz keybounc,key1 <br/> mov keydata,#04h ;Keydata = 04h <br/> ret <br/>; <br/>key2: jb row3,key3 ; idem <br/> djnz keybounc,key2 <br/> mov keydata,#08h <br/> ret <br/>; <br/>key3: jb row4,key4 ; idem <br/> djnz keybounc,key3 <br/> mov keydata,#0Ch <br/> ret <br/>; <br/>key4: setb col1 <br/> clr col2 <br/> jb row1,key5 <br/> djnz keybounc,key4 <br/> mov keydata,#01h <br/> ret <br/>; <br/>key5: jb row2,key6 <br/> djnz keybounc,key5 <br/> mov keydata,#05h <br/> ret <br/>; <br/>key6: jb row3,key7 <br/> djnz keybounc,key6 <br/> mov keydata,#09h <br/> ret <br/>; <br/>key7: jb row4,key8 <br/> djnz keybounc,key7 <br/> mov keydata,#0Dh <br/> ret <br/>; <br/>key8: setb col2 <br/> clr col3 <br/> jb row1,key9 <br/> djnz keybounc,key8 <br/> mov keydata,#02h <br/> ret <br/>; <br/>key9: jb row2,keyA <br/> djnz keybounc,key9 <br/> mov keydata,#06h <br/> ret <br/>; <br/>keyA: jb row3,keyB <br/> djnz keybounc,keyA <br/> mov keydata,#0Ah <br/> ret <br/>; <br/>keyB: jb row4,keyC <br/> djnz keybounc,keyB <br/> mov keydata,#0Eh <br/> ret <br/>; <br/>keyC: setb col3 <br/> clr col4 <br/> jb row1,keyD <br/> djnz keybounc,keyC <br/> mov keydata,#03h <br/> ret <br/>; <br/>keyD: jb row2,keyE <br/> djnz keybounc,keyD <br/> mov keydata,#07h <br/> ret <br/>; <br/>keyE: jb row3,keyF <br/> djnz keybounc,keyE <br/> mov keydata,#0Bh <br/> ret <br/>; <br/>keyF: jb row4,Nokey <br/> djnz keybounc,keyF <br/> mov keydata,#0Fh <br/> ret <br/>Nokey:mov keydata,#0FFh <br/> ret <br/>;================================ <br/>;The end of Keypad 4x4 subroutine <br/>;================================ <br/>end</span></td> </tr> </table></td> </tr> <tr> <td colspan="2" height="1" class="spaceRow"><img src="../../forum/templates/subSilver/images/spacer.gif" alt="" width="1" height="1"/></td> </tr> <tr> <td width="22%" align="left" valign="top" class="row2"><span class="name"><a name=""></a><b>cak kalim</b></span></td> <td class="row2" height="28" valign="top"><table width="100%" border="0" cellspacing="0" cellpadding="0"> <tr> <td width="100%"><img src="../../forum/templates/subSilver/images/icon_minipost.gif" width="12" height="9" alt="Post" title="Post" border="0"/><span class="postdetails">Posted: Tue May 09, 2006 2:23 am<span class="gen"> </span> Post subject: Reading key sequence from 4x4 keypad</span></td> </tr> <tr> <td colspan="2"><hr/></td> </tr> <tr> <td colspan="2"><span class="postbody">How to read 3 key sequence (example 4,5,6) from a keypad? <br/>If the sequence is correct then the led on. <br/> <br/>Have idea, pleasetell me.</span></td> </tr> </table></td> </tr> <tr> <td colspan="2" height="1" class="spaceRow"><img src="../../forum/templates/subSilver/images/spacer.gif" alt="" width="1" height="1"/></td> </tr> </table>
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