840z Zif Adaptor Problem

[-Dan-]

HI

Has anyone here got an melabs epic programmer?

i recently purchased the 840Z zif adaptor for it

when i insert the ribbon cable on the adaptor on to the 10 pin header on the programmer
the led on the programmer light's up constantly

and i get the "device does not match the target device" error from my programming software

i get the same problem wether in the 8-20 or 28-40 header.

Has anyone ever had this problem before ? its so annoying ahhhhhhhhhhh

[mister_e]

i don't have an EPIC, neither any 840z adapter but.. but assuming both male header have different use... is there any chance you have connected the ribbon to the wrong one
http://www.melabs.com/images/840z.jpg

[muddy0409]

I've had both, and the only problem I ever had was plugging onto the WRONG 10 way connector, or failing that, not orienting the target chip the right way around.

[-Dan-]

i don't have an EPIC, neither any 840z adapter but.. but assuming both male header have different use... is there any chance you have connected the ribbon to the wrong one
http://www.melabs.com/images/840z.jpg

yer definately connected to the right one

[-Dan-]

I've had both, and the only problem I ever had was plugging onto the WRONG 10 way connector, or failing that, not orienting the target chip the right way around.

did the led on the programmer stay on constantly tho ?

[muddy0409]

Dunno, too long ago to remeber.

[Darrel Taylor]

Which PIC are you using?
And which way did you plug it in?

See ...
http://www.crownhill.co.uk/images/product/melabs/8-10-zif-datasheet.jpg
<br>

[-Dan-]

Which PIC are you using?
And which way did you plug it in?

See ...
http://www.crownhill.co.uk/images/product/melabs/8-10-zif-datasheet.jpg
<br>


the ribbon cable is on the right 10 pin header

pic is in the zif socket correctly

contacted melabs and they said the led should not come on when i connect the adaptor

they said its probably a faulty adaptor

just my luck!

[Darrel Taylor]

I hate to disagree with melabs support, ... but ...
I just have a hard time believing that.

There's nothing on the adapter itself that can fail.
Unless there's some burnt traces or something. (which you would probably see)

You never did answer the questions ...

Which PIC are you using?
Which way did you plug it in?

It's one thing to say it's correct, but for someone else to help troubleshoot, it makes it easier to know the actual details, so that the problem can be dismissed.

Assuming that the answer to both questions is indeed "They are the correct way".
I would be more likely to believe there's a problem with the ribbon cable, instead of the adapter itself.

And there's a few ways to find out.
1. replace the ribbon cable.
2. use an ohmmeter to test for shorts or opens in the ribbon.
3. visually insure that each conductor lines up with the correct Pins on the IDC connectors.

I just can't see one of those adapters failing on it's own.
<br>

[-Dan-]

HI Darrel

i'm using the 16f870, ive connected the ribbon cable and inserted the pic in to the adaptor as in the attatched diagram.

i have done a continuity test on the ribbon cable, and all seems ok and there seems to be no shorts.

i see what your saying about not much can go wrong with the adaptor, its basically a zif socket on a pcb.


why can't things just work when you plug them in :( haha




I hate to disagree with melabs support, ... but ...
I just have a hard time believing that.

There's nothing on the adapter itself that can fail.
Unless there's some burnt traces or something. (which you would probably see)

You never did answer the questions ...

Which PIC are you using?
Which way did you plug it in?

It's one thing to say it's correct, but for someone else to help troubleshoot, it makes it easier to know the actual details, so that the problem can be dismissed.

Assuming that the answer to both questions is indeed "They are the correct way".
I would be more likely to believe there's a problem with the ribbon cable, instead of the adapter itself.

And there's a few ways to find out.
1. replace the ribbon cable.
2. use an ohmmeter to test for shorts or opens in the ribbon.
3. visually insure that each conductor lines up with the correct Pins on the IDC connectors.

I just can't see one of those adapters failing on it's own.
<br>

[muddy0409]

Hmmm...Blowed if I can find mine after my 3000km re-location.
Just to humour me, connect the ribbon to the other header on the adaptor, It's a long time since I used mine, but with all this discussion, I seem to recall I had some similar problems and changing things like that fixed them??

And as a further follow up, I think there is something about the labeling that is easily confusing..

[-Dan-]

ive just noticed something about the ribbon cable

forgive my crude drawings here mspaint was a quick option.

This is how my ribbon cable is :

<img src="http://img106.imageshack.us/img106/17/ribboncable1lg1.jpg"></img>


I'm just wondering should it be like this :


<img src="http://img126.imageshack.us/img126/8946/ribboncable2qa8.jpg"></img>

[Darrel Taylor]

My cable is like your first picture.
Both keys face the same direction.

Just wondering if you've ever programmed any chips with that EPIC before?
Does the problem only happen with that adapter?
Or has it never worked on anything.

Do you have an 18-pin PIC that you can try to program in the EPIC's ON-Board socket?
Might eliminate questions about the adapter if it won't program an 18-pin.

Have you gone through the EPIC troubleshooting guide ...
http://www.melabs.com/support/epicfixs.htm
<br>

[duncan303]

I have dug out an melabs zif convertor, I personally use the RS232 serial melabs programmers, and am not familiar with the epic programmer.

I have taken a couple of photos
<img width="342" height="256" src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=2225&stc=1&d=1199215653"/> (http://www.picbasic.co.uk/forum/attachment.php?attachmentid=2225&d=1199204528) <img width="371" height="278"src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=2226&stc=1&d=1199215653"/> (http://www.picbasic.co.uk/forum/attachment.php?attachmentid=2226&d=1199204544)

As can be seen the tracks on the board are fairly straighforward but more importantly they are also substantial for the task, the PCB is also good quality, I would suggest that the chances of the board itself failing, probably should be ignored; Likewise the zif socket. In any event the continuity check would have revealed any of the five connections failing.

Melabs do not use boxed headers on either this module or the programmer and I have several times misaligned the IDC socket onto the pin headers as supplied. When this happens I curse them for not providing a boxed header, alternativly I am pleased as most of my connectors I make up and then I do not have to worry about the orientation when clamping the socket.

The led on my serial programmer is a tri-colour, green when power on and red when programming, am I correct in assuming that yours is red all the time you are connected, this would possibly suggest that the socket indeed might not be correctly aligned.

Just another thought (rethink) perhaps there could be residual conductive material floating about inside the zif.
Am now considering how the masking is done during wave soldering on a zif, is it a post assembled component. I regret that the Zif is about to become discombobulated shows how bored I am at Christmas

[-Dan-]

Hi thanks for the the pics ^

i found the problem the adaptor seemed ok so i looked at the programmer and found that for some mad reason the 10 pin header on my programmer is not oriented correctly.

Instead of pin 1 being the bottom right, on mine it is the top left so its basically the wrong way round.