basic question regarding burning pic

[afesheir]

Dear everyone ..
I'm trying to program PIC16F877A using JDM serial programmer and IC-PROG. I've got a successful verification message from IC-PROG, so I removed the PIC from JDM and installed it on bread board with appropriate Vdd on Pin 11 & 32 and Vss on Pin 12 & 31. I've connected 8MHz crystal with two capacitors on pins 13 & 14 and pulled MCLR pin up to Vdd. The problem that there is no output at all (the hex file is actually a simple flasher program just for test)

Any help or support is very appreciated and most welcome

Regards

 

[wp100]

Hi,

You really need to post your code in case you have a error there.

Hardware wise, have you got the led to the right port, connected the right way around and fitted with a 330 to 470 ohm series resistor ?

As to if you chip has programmed correctly, take it out of your circuit and using your programmer 'Read' the chips contents and see if they are the same as your hex file.

edit - its also a know problem that with the crystals wire being to thin you cannot always get a good connection on a breadboard, so soldering the crystal ansd caps on to a bit of board with thicker wires is better.
The Crystal and caps must be on short leads as close to the pic pins as possible.

 

[afesheir]

hi

void main ()
{
TRISB=0;
while (1)
{
PORTB=1;
delay_ms(1000);
PORTB=1;
delay_ms(1000);
}
}

and I've connected one led to B0 pin with the appropriate resistor ..

OK, if the content is identical to the hex file, why doesn't the circuit operate as expected ??

 

[wp100]

Hi,

I am not into C, but surely the second PORTB should be PORTB=0;

 

[afesheir]

Oops .. I've miss-written the code here in the board, but it's ok in mikroC .. and even .. if both PORTB are 1, I should have gotten the LED lighting, but really it is off