12C671 - GP3 problem

[financecatalyst]

Hi, thanks for the reply.
I did changed the config and enabled the WDT. The code looks like this now:

DEFINE OSC 4
Define OSCCAL_1K 1
@ __CONFIG _INTRC_OSC_NOCLKOUT & _WDT_ON & _PWRTE_ON & _MCLRE_OFF & _CP_ALL
'// For PIC12C671
include "modedefs.bas"

'// Define variables
ToTx VAR GPIO.0
PAUSE 30 
'// OSCCAL=0
TRISIO = %111110 
OPTION_REG = %10001000
ToTx = 0 
INTCON=0 
ADCON0.0=0
ADCON1=7

send:
if gpio.1=0 then
serout ToTx,N2400,["G0"]
Low ToTx
pause 10
endif

if gpio.2=0 then
serout ToTx,N2400,["G1"]
Low ToTx
pause 10
endif

if gpio.3=0 then
serout ToTx,N2400,["G3"]
Low ToTx
pause 10
endif

if gpio.4=0 then
serout ToTx,N2400,["G4"]
Low ToTx
pause 10
endif

goto send
end

My circuit only gets power when any button is pressed. I can try to scan the paper after drawing the circuit or try to find a software over the net if you think the circuit could be the culprit.
But I would like to add that rest all the buttons are working fine, so I believe the circuit is ok, GP3 is connected the same way as all other pins. Even the voltage on that pin behaves the same way as on any other pin under same circumstances but no DATA OUTPUT is there.

[mackrackit]

Can you try making GPIO3 active high?

[financecatalyst]

Yes I can do it to check but I really need to find an answer to make it work Active Low. I will reply with an update with Active High.

[financecatalyst]

I tried one method in which I gave continues supply to the PIC for 5v. All pins work fine as expected (Active Low).
The problem of GP3 only strikes when circuit gets power only when button is pressed and pin is made low.

[malc-c]

Not sure about the 12C chip, but on 12F series GPIO3 is the MCLR pin and what could be happening is by grounding this you are resetting the PIC - there is a way of disabling the reset function on the 12F series, so you might need to do the same on the 12C chip

[financecatalyst]

Not sure about the 12C chip, but on 12F series GPIO3 is the MCLR pin and what could be happening is by grounding this you are resetting the PIC - there is a way of disabling the reset function on the 12F series, so you might need to do the same on the 12C chip

Hi, I already have disabled the MCLR - (in Config). I also mentioned in the post above that PIC works fine when 5V supply is continues. Thanks

[mackrackit]

PIC works fine when 5V supply is continues.

What exactly do you mean?