12C671 - GP3 problem

[financecatalyst]

When I put 5V continues supply i.e. system already gets +ve & -Ve 5V and does not depend on button press for -Ve. Then lowering GP3 does result in serout data.

In other words, pic gets its 5V continues and all pins pulled high with 10K. Lowering any pin results in serout data.

[malc-c]

i.e. system already gets +ve & -Ve 5V and does not depend on button press for -Ve.

Are you applying 10V across the supply pins ? - I thought most pics will only work on 5V (ie +5v and 0V supply lines)

[financecatalyst]

No, it is 5V only. i.e. +5V & 0V.

[Acetronics2]

Hi, FC

My circuit only gets power when any button is pressed.

Reading that , ... I think you didn't show or tell us everything :

OR the code shown only is a part of ...

OR you should show the Hardware side ...

no way for us to help further not knowing what you did and how you did it ...

Alain

[financecatalyst]

Hi, I have attached the schematic and this is the complete code I have shown here. Hope to find a solution soon.

[mackrackit]

The way I read this, from the data sheet

Most other registers are reset to a “reset
state” on Power-on Reset (POR), MCLR Reset, WDT
Reset, and MCLR Reset during SLEEP

Every time you press the GPIO.3 button the chip will go into a continuous reset.
The chip never gets to read the configuration to see that MCLR is turned off.

[malc-c]

Hi, I have attached the schematic

Comments:

1) - There are no smoothing capacitors either side of the regulator - what are you using to provide the 12v supply. If it's simply a bridge rectifier off a transformer then the supply will need smootthing.

2) - I assume the diodes are LEDS ? If so then you would be better off putting them in series with the resistors rather than in parallel.

3) - If they are not LEDS, then try removing them from the circuit, there may be some reverse bias or something causing the current to flow and possibly short out the supply ?

As Dave has mentioned - It does sound as if you are constantly resetting the chip before it configures itself.

[aratti]

With reference to your schematic, I am sure you have mistaken in drawing it, while the hardware is correctly wired, otherwise you will short the 12 Volts as soon as you connect it to the circuit. ( see the snap posted and compare it with your circuit)

As far as the code is concerned, I would place a delay below the label send

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

Al.