4x4 keypad Help

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4x4 keypad Help

Hi all
i am using a 18f452 with the 4 x4 keypad connected to portB
this is on the proton Development board and the connections are as the attachment below
All is get displayed on my lcd is

" Keypad Test "
"Press any key"
I have ran the program on micro studio ICD and the program seems to be struck
in this loop
==========================================
getkeyu:
' Wait for all keys up
PORTB = 0 ' All output pins low
TRISB = $f0 ' Bottom 4 pins out, top 4 pins in
If ((PORTB >> 4) != $f) Then getkeyu ' If any keys down, loop

Pause 50 ' Debounce
================================================== ====

Is there something i am missing
i have the complete code below and

================================================== ==============
DEFINE LOADER_USED 1 ' uses a bootloader

@ __CONFIG _CONFIG1H, _OSCS_OFF_1H & _HS_OSC_1H

Define OSC 20
clear

DEFINE LCD_DREG PORTD ' Use Portd for LCD Data
DEFINE LCD_DBIT 4 ' Use Upper(4) 4 bits of Port
' PORTD-4 thru PORTD-7 connects to
' LCD DB4 thru LCD DB-7 respectively
DEFINE LCD_RSREG PORTE ' PORTE for RegisterSelect (RS) bit
DEFINE LCD_RSBIT 0 ' PORTE-0 pin for LCD's RS line
DEFINE LCD_EREG PORTE ' PORTE for Enable (E) bit
DEFINE LCD_EBIT 1 ' PORTE-1 pin for LCD's E line

DEFINE LCD_BITS 4 ' Using 4-bit bus
DEFINE LCD_LINES 2 ' Using 2 line Display
DEFINE LCD_COMMANDUS 2000 ' Command Delay (uS)
DEFINE LCD_DATAUS 50 ' Data Delay (uS)

' ** Define LCD Control Constants **

I CON 254 ' Control Byte
Clr CON 1 ' Clear the display
Line1 CON 128 ' Point to beginning of line 1
Line2 CON 192 ' Point to beginning of line 2
Line3 CON 148 ' Point to beginning of line 3
Line4 CON 212 ' Point to beginning of line 4

'
' Initialise Hardware
' -------------------

TRISA=%00000000
TRISB=%00000000
TRISC=%10000000
TRISD=%00000000

INTCON2.7 = 1 ' Enable PORTB pullups
ADCON1 = 7 ' Make PORTA and PORTE digital
Low PORTE.2 ' LCD R/W low (write)

Pause 1000 ' Wait for LCD to start

lcdout I,Clr:Pause 30
lcdout I,Line1," Keypad TEST "
lcdout I,Line2,"..Power On.. !!"

' Define program variables
col var byte ' Keypad column
row var byte ' Keypad row
key var byte ' Key value

lcdout I,Clr:Pause 30
lcdout I,Line1," Keypad Test "
lcdout I,Line2, "Press any key" ' Display sign on message

loop: Gosub getkey ' Get a key from the keypad
lcdout I,Clr:Pause 30
lcdout I,Line3, #key
Pause 50
Goto loop ' Do it forever

' Subroutine to get a key from keypad
getkey:
Pause 50 ' Debounce

getkeyu:
' Wait for all keys up
PORTB = 0 ' All output pins low
TRISB = $f0 ' Bottom 4 pins out, top 4 pins in
If ((PORTB >> 4) != $f) Then getkeyu ' If any keys down, loop

Pause 50 ' Debounce

getkeyp:
' Wait for keypress
For col = 0 to 3 ' 4 columns in keypad
PORTB = 0 ' All output pins low
TRISB = (dcd col) ^ $ff ' Set one column pin to output
row = PORTB >> 4 ' Read row
If row != $f Then gotkey ' If any keydown, exit
Next col

Goto getkeyp ' No keys down, go look again

gotkey: ' Change row and column to key number 1 - 16
key = (col * 4) + (ncd (row ^ $f))
Return ' Subroutine over

End

Best Regards
Sabu

Yes it will stuck, you need some pull-up resistors in that. You can enable the PIC internal one

Code:

INTCON2.7=0

Just saw you already did.. just the wrong way ;)

AND you WILL have erratic results with this routine... add a PAUSEUS 5 in this section

Code:

TRISB = (dcd col) ^ $ff ' Set one column pin to output PAUSEUS 5 row = PORTB >> 4 ' Read row

Thank mister_e for your reply
i am a bit confused by what you mean by

just the wrong way ;)

Also without doing anything else to the program apart from changing the Enable PORTB pullups line when i used a 16f877a

================================================== =
OPTION_REG.7 = 0 ' Enable PORTB pullups for 16f877a
'INTCON2.7 = 1 ' Enable PORTB pullups for 18f452
================================================== =

the program works fine could it be my pic?

Best Regards
Sabu

In your first post you used...
INTCON2.7=1

But this actually DISABLE the internal pull-up...

Use
INTCON2.7=0
instead, and the problem will disapear

Oops silly me
it works fine

thanks a lot

Sabu

warning unable to include keypas.bas and lcd.bas

i using pic18f4550 and PICBASIC PRO version 1.0 as my compiler..
while i compile my program below, there is warning which is

unable to include file keypad.bas
unable to include file lcd.bas..

this is my source code...

Code:

'**************************************************************** '* Name : UNTITLED.BAS * '* Author : [select VIEW...EDITOR OPTIONS] * '* Notice : Copyright (c) 2010 [select VIEW...EDITOR OPTIONS] * '* : All Rights Reserved * '* Date : 10/5/2010 * '* Version : 1.0 * '* Notes : * '* : * '**************************************************************** Include "modedefs.bas" DEFINE PIC18F4550 DEFINE OSC 4 INCLUDE "KeyPad.bas" ' ( mister_e 's great keypad include file ) INCLUDE "lcd.bas" CMCON = 7 ADCON1 = 7 TRISD = %00000000 TRISB = %11111111 '// Declare Variables... Col_A VAR PORTB.0 Col_B VAR PORTB.1 Col_C VAR PORTB.2 Col_D VAR PORTB.3 Row_A VAR PORTB.4 Row_B VAR PORTB.5 Row_C VAR PORTB.6 Row_D VAR PORTB.7 Scan_Col VAR BYTE ' Counter - current col Key_Press VAR BYTE ' Value of key (0-9) & * + # + A + B + C + D Key_Down VAR BYTE ' Flag set true when key is depressed Allow_Key VAR BYTE ' Flag - disallow multiple keys being pressed I VAR byte ' General working var Scan_Keypad: @ incf _Scan_Col, 1 ' Inc col pos... SELECT CASE Scan_Col ' Col (1-4) CASE 1 Col_A = 0 ' Switch on col (active low) Col_B = 1 ' Col off Col_C = 1 ' Col off Col_D = 1 ' Col off '// 1 Key IF Row_A = 0 THEN ' Key down? ... IF Allow_Key = 0 THEN ' Any other key down? Key_Press = 1 ' Load var w/value of key Allow_Key = 1 ' Disallow other keys ENDIF ENDIF '// 4 Key IF Row_B = 0 THEN IF Allow_Key = 0 THEN Key_Press = 4 Allow_Key = 1 ENDIF ENDIF '// 7 Key IF Row_C = 0 THEN IF Allow_Key = 0 THEN Key_Press = 7 Allow_Key = 1 ENDIF ENDIF '// * Key IF Row_D = 0 THEN IF Allow_Key = 0 THEN Key_Press = 42 Allow_Key = 1 ENDIF ENDIF CASE 2 Col_A = 1 Col_B = 0 Col_C = 1 Col_D = 1 '// 2 Key IF Row_A = 0 THEN IF Allow_Key = 0 THEN Key_Press = 2 Allow_Key = 1 ENDIF ENDIF '// 5 Key IF Row_B = 0 THEN IF Allow_Key = 0 THEN Key_Press = 5 Allow_Key = 1 ENDIF ENDIF '// 8 Key IF Row_C = 0 THEN IF Allow_Key = 0 THEN Key_Press = 8 Allow_Key = 1 ENDIF ENDIF '// 0 Key IF Row_D = 0 THEN IF Allow_Key = 0 THEN Key_Press = 0 Allow_Key = 1 ENDIF ENDIF CASE 3 Col_A = 1 Col_B = 1 Col_C = 0 Col_D = 1 '// 3 Key IF Row_A = 0 THEN IF Allow_Key = 0 THEN Key_Press = 3 Allow_Key = 1 ENDIF ENDIF '// 6 Key IF Row_B = 0 THEN IF Allow_Key = 0 THEN Key_Press = 6 Allow_Key = 1 ENDIF ENDIF '// 9 Key IF Row_C = 0 THEN IF Allow_Key = 0 THEN Key_Press = 9 Allow_Key = 1 ENDIF ENDIF '// # Key IF Row_D = 0 THEN IF Allow_Key = 0 THEN Key_Press = 35 Allow_Key = 1 ENDIF ENDIF CASE 4 Col_A = 1 Col_B = 1 Col_C = 1 Col_D = 0 '// A Key IF Row_A = 0 THEN IF Allow_Key = 0 THEN Key_Press = 65 Allow_Key = 1 ENDIF ENDIF '// B Key IF Row_B = 0 THEN IF Allow_Key = 0 THEN Key_Press = 66 Allow_Key = 1 ENDIF ENDIF '// C Key IF Row_C = 0 THEN IF Allow_Key = 0 THEN Key_Press = 67 Allow_Key = 1 ENDIF ENDIF '// D Key IF Row_D = 0 THEN IF Allow_Key = 0 THEN Key_Press = 68 Allow_Key = 1 ENDIF ENDIF Scan_Col = 0 END SELECT LCDOUT $fe,1 LCDOUT " Key_Press " '// Check for key release, all cols on (active low) ... Col_A = 0 Col_B = 0 Col_C = 0 Col_D = 0 IF Row_A = 1 THEN IF Row_B = 1 THEN IF Row_C = 1 THEN IF Row_D = 1 THEN Allow_Key = 0 Key_Down = 0 Key_Press = 255 ENDIF ENDIF ENDIF ENDIF GOTO Scan_Keypad

please help me...
thank you...

Hi,
Do you have those two files, KeyPad.bas and lcd.bas in the same folder as your source file that you're trying to compile?

With that said, PBP1.0 sounds REALLY old, are you sure that is the cirrect version. And lastly, there's really no need to post the same question in three different threads, one would've been enough.

/Henrik.