Portc 16F913 problem

[Andre_Pretorius]

Hi all
I am trying to use a PIC16F913 to read a keypad, the problem is i can not get PortC.2 to go to a high state ,can anyone please point me in a direction, Pin 0 and 1 works fine

INCLUDE "MODEDEFS.BAS"
Asm
    ERRORLEVEL -306
Endasm

DEFINE OSC 20    ' Define crystal as 20Mhz
LCDCON = 0
TRISC = %11110000   'Set PORTC for keypad   
TRISB = %00000000   'Sert PORTb as outputs and for use with the ICD2
VAR1 VAR BYTE
VALUE VAR BYTE
PortB.0 = 0
 
keyPad: portc=1
  
  if portc.4=1 then
  for VAR1=0 to 10
   if portc.4=1 then VAR1 = 0
  next
  VALUE=1 
  goto getPin
  endif
  if portc.5=1 then
  for VAR1=0 to 10
   if portc.5=1 then VAR1 = 0
  next
  VALUE=4 
  goto getPin
  endif
  if portc.6=1 then
  for VAR1=0 to 10
   if portc.6=1 then VAR1 = 0
  next
  VALUE=7 
  goto getPin
  endif
  if portc.7=1 then
  for VAR1=0 to 10
   if portc.7=1 then VAR1 = 0
  next
  VALUE=10 '* button
  goto getPin
  endif
  portc=2
  if portc.4=1 then
  for VAR1=0 to 10
   if portc.4=1 then VAR1 = 0
  next
  VALUE=2 
  goto getPin
  endif
  if portc.5=1 then
  for VAR1=0 to 10
   if portc.5=1 then VAR1 = 0
  next
  VALUE=5 
  goto getPin
  endif
  if portc.6=1 then
  for VAR1=0 to 10
   if portc.6=1 then VAR1 = 0
  next
  VALUE=8 
  goto getPin
  endif
  if portc.7=1 then
  for VAR1=0 to 10
   if portc.7=1 then VAR1 = 0
  next
  VALUE=0 
  goto getPin
  endif
  portc=4
 
  if portc.4=1 then
  for VAR1=0 to 10
   if portc.4=1 then VAR1 = 0
  next
  VALUE=3 
  goto getPin
  endif
  if portc.5=1 then
  for VAR1=0 to 10
   if portc.5=1 then VAR1 = 0
  next
  VALUE=6 
  goto getPin
  endif
  if portc.6=1 then
  for VAR1=0 to 10
   if portc.6=1 then VAR1 = 0
  next
  VALUE=9 
  goto getPin
  endif
  if portc.7=1 then
  for VAR1=0 to 10
   if portc.7=1 then VAR1 = 0
  next
  VALUE=11 '# button 
  goto getPin
  endif
  goto keypad
getpin:
PortB.0 = 1
return
 
END

[Demon]

For starters, GETPIN is a subroutine, use GOSUB to call it, not GOTO.

Robert

[Andre_Pretorius]

Thanks i'll do so - I did a bit of reading and it seems it has something to do with the "read modify write" functions on portC.2 and 5.
I moved the pins to portB as they are spare and all seems to be working now

[shahidali55]

On 16F913, Port C is shared with the VLCD module. To uses this as digital I/O, you will need to clear the VLCDEN bit in LCDCON register.