Problems with PIC16F628A LED flashing

[jacofaj]

Hi,

This is my first time using Micro C, I am tring to program a simple LED flashing on a PIC16F628A.
But I can't get it to work. My code looks like this:

#include "built_in.h"

void main(){

TRISA = 0x00;
PORTA = 0x00;
CMCON = 0x07;

while(1){

PORTA = 1;
Delay_ms(1000);
PORTA = 0;
Delay_ms(1000);
}
}

Please Help!

[pepesz]

Where is your LED connected? Should be to RA0 if it has to work with your code.
If you want to modify only one pin use PORTA.F0 = 1 or 0; where Fx is PORT pin number

[Stefan Uhlemayr]

Hi,

This is my first time using Micro C, I am tring to program a simple LED flashing on a PIC16F628A.
But I can't get it to work. My code looks like this: ...

Have a look to this compilation of useful links:
http://www.microchip.com/forums/fb.aspx?m=358934
In the second chapter "General Circuit-Design-Questions:", you will find the link "Help, my first PIC-project won't work:". In this post from Dale you will find the most common problems mentioned, why the PIC doesn't work as expected.
Btw, your code looks good, as far as I can say.

Hope this helps,
Stefan

[jacofaj]

Hi,

I tried all the advice, but no success.

I think it is in my configuration.
so if any one can give me an example of
the required config for a PIC16F628A with internal osc,
it will help.

Thanks
Jaco

[CVMichael]

Are you aware that PORTA = 1 only sets the first bit ON ?

I think you should have:
PORTA = 255;
Or
PORTA = 0xFF;
Or
PORTA = 0b11111111;

(All 3 above are doing exactly the same thing).

If you want to set only one bit (pin), then you should call it like this: PORTA.F0 = 1;

[MD5]

Thx Michael,

Can we set in the application the porta status in Decimal, portb in hex or binary?

Example:
PORTA = 255;
Or
PORTB = 0xFF;

Just for info...

Regards,
Sam

[Mince-n-Tatties]

Thx Michael,

Can we set in the application the porta status in Decimal, portb in hex or binary?

Example:
PORTA = 255;
Or
PORTB = 0xFF;

Just for info...

Regards,
Sam

yes you can... and the format is as shown by CVMichael above. you can have any combination within the same source code. you can even use different formats on the same port at different times in the same source.

e.g this is perfectly valid (duplication for demo purpose, but you could do it if you want)

TRISA = 0x0;
TRISA = 0b00000000;
TRISA = 0;

// an 8 bit memory walk
PORTA = 255;
PORTA = 0xAA;
PORTA = 0b01010101;
PORTA = 0;

[jacofaj]

Hi,
Solved the problem.
It was in the config.

Thanks for all your help!!!

[congduc1352]

Hi,
Solved the problem.
It was in the config.

Thanks for all your help!!!

how you config sir?
im stucking here for afew day