PICKit2 and PIC18F4550 problem.

Hello

I've recently bought myself a PICKit2 to use instead of my previous Velleman VM134 and it seems to work fine, had no problems writing to any of my PIC16F. But when it comes to the PIC18F4550 my only of the P18F family that I own, then I'll have to write several times to make the darn thing programmed??

When I use the programming software that came with the PICKit2 it says something like "... configuration bits are not set.." every time I load any of my .hex files and that I should in MPLAB export the file with configuration bits. And If I do like it says, I will still get the same result in the PICKit2 software and it never works. If I use MPLAB all the way, then the programming works fine some of the times maby not on the first click but after I've been clicking the write button about five - ten times, then there might be a program on the chip.

Why do I have to program P18F sever times to get the code on the chip? :sad: Anyone else who got this problem with the P18F4550? I had almoust the same problem with my Velleman VM134, but here it was only writing a bit of the code to the chip.

Here is my code, that works some of the times:


Regards

/ Morgan

Hi,

Don't have a 4550 chip to hand to replicate your problem - but I have prgrammed that chip without problems.

First - the code you posted is incomplete and does not build.

Add these to lines to the beginning of your code so MPlab knows what chip you are talking about.


Then check your mplab settings, goto Configure, Cofigure Bits and then see that the check box at the top left " configuaration bits set in code " is Ticked On.


Also when you specify your user Registers Delay1 it automatically assumes you want just one byte, so there is no need to use the :1 unless you want create more.

wp100, I've checked it all now. Still it does only write some of the times when I'm clicking the button which I think is wierd, because if something was wrong it shouldn't work at all, but it does.
I don't get it, why not everytime.

And I must add that it's not reporting that anything went wrong, there's just nothing there when I read back and I've even tried it in circuit. And every once in a while the code has been written to the chip.

Thanks

/ Morgan

Hi,

A few questions before I can answer -

First how have you got your 4550 chip connected to the Pk2, in its own socket, in a circuit board or on a breadboard ?

How long are the leads from the Pk2 output socket to the 4550 ?

You say you are pressing 'the button' - which ? - the red button on the Pk2 ?

How are you using the PK2, from the Programmer selection in Mplab or the stand alone PK2 V2.61 program.

Think knowing all that we can then see whats going wrong.

Hello

wp100 said:

First how have you got your 4550 chip connected to the Pk2, in its own socket, in a circuit board or on a breadboard ?

Click to expand...

It's on a breadboard.

wp100 said:

How long are the leads from the Pk2 output socket to the 4550 ?

Click to expand...

Just about 2 inches

wp100 said:

You say you are pressing 'the button' - which ? - the red button on the Pk2 ?

Click to expand...

The icon button in MPLAB writing section.

wp100 said:

How are you using the PK2, from the Programmer selection in Mplab or the stand alone PK2 V2.61 program.

Click to expand...

Both, I've tried both but it was only working some of the times in MPLAB and never in the stand alone.

/ Morgan

Hi,

Well that all sounds normal with good short leads to the 4550 chip.

Assume ? you have got nothing else connected to the 4550 other than the 5 leads from the PK2 ?

While it should program up on the breadboard they can cause occassional wierd problems due to bad connections - if you have a spare 40 pin dil socket I would be tempted to solder the leads from the pk2 to the dil socket pins so there is no chance of poor connections.

If it still fails to work then send over both the full assembler file you are using plus the built .hex file together with the Mplab Project files, .Mcp & .Mcw, so we can reproduce your situation fully.
Will pinch a 4550 and try programming it with your project code.

Hi,

Just another way to do things - this is a working program for the 4550.

Simply start the stand alone program pk2 v2.61 you should then be able to 'Import' this file then 'write' it to the chip in a few seconds.

Can you do that without problems ?

wp100 said:

Hi,

Well that all sounds normal with good short leads to the 4550 chip.

Assume ? you have got nothing else connected to the 4550 other than the 5 leads from the PK2 ?

While it should program up on the breadboard they can cause occassional wierd problems due to bad connections - if you have a spare 40 pin dil socket I would be tempted to solder the leads from the pk2 to the dil socket pins so there is no chance of poor connections.

If it still fails to work then send over both the full assembler file you are using plus the built .hex file together with the Mplab Project files, .Mcp & .Mcw, so we can reproduce your situation fully.
Will pinch a 4550 and try programming it with your project code.

--------------------------------------------------------------------------------

Hi,

Just another way to do things - this is a working program for the 4550.

Simply start the stand alone program pk2 v2.61 you should then be able to 'Import' this file then 'write' it to the chip in a few seconds.

Can you do that without problems ?

Click to expand...

Hello wp100

Sorry for my delay..
I'll try to use a dil socket instead when I come home from work today, and try using your attached file to see how that works then I'll be back for status report. Thank you, I believe it could be the problem with poor connections like you're saying.

/ Morgan