pic16f877a programing

[jcleaver]

trying to program this chip and running in to problems writeing the hex file
i believe it has something to do with the electrical hookup
i am using the icsp hookup on my programmer
following connections to the pic
1-vpp 40- pgd 39-pgc 11&32-vdd 12&31-vss
in addition i have a crystal across 13-14 and a 10k to vss on pin 36
i can program very small programs 1 t0 3 lines but the pic still does not run
anything else get errors

thanks for your help

[mister_e]

How the MCLR/VPP pin? Did you place a 10K+Diode to VCC?
How about the capacitor around your crystal? Wich value?
What crystal speed do you use?

What is the malicious code?

How about if you remove the ICSP header once your PIC is Programmed?

What is your device programmer? What is your device programmer software?

[jcleaver]

try to answer the programmer is a velleman and works great with the onboard sockets but does not have a 40 pin thus the icsp the boardf has some circuirty to the vpp pin and like i sai it works fine on other chips

as for as the errors i get is verfify errors but even when i try to write a small program like blink i get no errors but hte chip is not operating any thing else get errors

the crystal is 20 with 22pf to vss

[Srigopal007]

First off you need to have a 10K resistor going from VCC(+5V) to the MCLR pin. Also if you are doing ICSP by using a PICSTART, you might want to supply your own 5V power instead of letting the PICSTART supply the power. This might by what your problem is. Please report back with results. maybe we can help out more depending on waht results you get.

Srig

[jcleaver]

ok will try that it should be noted that there is no other connections to the pic just trying to program using my programmer which has worked on all other chips but does not have a 40 pin scocket thats why i built a little breadboard and extened the five wires listed on my first request to the pic

[jcleaver]

this did not help. think it might have been worse the programmer i am using is already holding thge pin at 10 volts in the program mode adding the resistor drains this, errors i am getting are all failed to verfy. more ideas please