hi everyone,
I've got a problem when I try to burn my 16f84. Each time I try to burn it at the end an error message appears :" Verify failed at address 0x0000" .
I thought it might have come from the MC but with a new one it doesn't work either. I use the Pro Pic 2 Programmer from http://www.tavernier-c.com/programmateur_de_pic.htm on win Xp (with driver for IC prog) and I never had any problem before. I really don't understand to origin of the problem; I hope somebody might help me.
Thanks a lot for your answers.
See u

 

The most usual cause is too little voltage on the MCLR pin, this is used to force the PIC to prgramming mode - if it doesn't switch to programming mode you can't write to it, and a verify obviously fails at the first byte (0x0000.

This is often caused by using unregulated 'wall wart' PSU's, try using two 9V batteries in series to feed the programmer - I ran mine like that for many years.

 

what's supposed to be the voltage on MCLR pin?

 

13V - but with an unregulated PSU it may read 13V on a meter, but have high ripple content which prevents it working. Providing a clean 18V DC (as with two 9V batteries) ensures a good supply - you start getting the same error message when the batteries get too low.

 

but I don't understand , my PSU is regulated. I use a 78L05 and a 78L08. I check on the MCLR pin and I've got 12,15 v and when I send datas it goes until 12,65v. I've also made a hardware test with IC prog and it works, it gives 12.65v. Don't u think it's enought to switch in programming mode??

 

I was refering to the PSU you are feeding the programmer from, not the internal voltage regulators on the programmer. For a smooth 13V output from the 78L08 you need at least 16V or so DC going in, the ripple must not drop below this or the voltage regulator will drop out (stop regulating).

You've never mentioned what you are feeding it from, nor if it's regulated or not.

 

well it's still doesn't work!
I've remove the AC PSU and supplied my 78l05 and 78l08 with 20v DC.
And It's still doesn't work.Still de same error. I really don't understand because it used to work.And now always the same error (verify failed at address 0x0000) or when I try to load other programs it sometimes display "verify failed at address 0x0004". Do u see another solution?
Thanks a lot for giving me your time and your help

 

Well, you said you've tried a different computer, so presumably it's not that - although some computers just don't seen to work (particularly laptops).

Have you tried another PIC - in case that ones died?.

 

Are you using the same cables as before (when it worked). Cables between pc and programmer , and between programmer and pic should be shielded and not too long...

wonder how many times i posted this sentence the last few months ? :lol:

 

Hi all,
I have both a serial port programmer and a parallell port programmer. With the serial port programmer I use IC Prog. Had the same problem till I realised I had the wrong com port selected in the software. I know it sounds silly but check you have correct com port selected!
Hope it helps. ( I use both programmers from my Dell laptop)
Barry
PS. With my P40Pro programmer I use WinPicProg. Never a problem. Thank Nigel!!!

 

Ooooops! Should read Thanks Nigel

 

I'm not to an 's' :lol: