Shield made by me makes arduino unrecognized to PC

Hy i have an arduino duemilanove with ATMEGA 328P and i have a shield connected him but it give me an error on the PC saying that windows does not recognize the USB device and the RX and TX leds do not turn off unless I remove the shield and connect the arduino without the shield .... so he can already recognize the device that I built to arduino work properly.
nobody is aware of the problem?I have looked in forums and I can not find anyone with this problem...
please help me, I would apreciate a lot...

Your shield probably has an electrical problem. We will need to see the schematic.

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My guess is that the electrical problem is a short circuit. Check the arduino voltage when it is plugged in.
the scematic is this and I have already verified and it doesn't have any CC

P.S. the arduino work properly without the shield but if I connect the PC with the arduino shield in place it lights up the arduino RX and TX leds and not recognize the card, but if I connect the Arduino to the USB and only afterarduino being recognized I connect the shield on top of the Arduino and it works correctly ... are you understand me?

Are you sure those resistors are 10K? What are the colors on the resistors? Do you have anything connected to the PAD terminals?

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yes I'm sure that resistors are 10k and, the colors are orange black and brown, and at last the is I have nothing connected to the pads terminal...I mean, I have some wires but the wires do not have external power or is oin short-circuit...

I can only think of 2 random things then:

  1. Are you sure you're aligning your shield properly when you plug it in? Any chance you're off by 1 pin?

  2. Those traces that come from pins 2 and 4 are very close to the nearby pads. Could there be a little piece of copper or something shorting them?

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  1. yes they are all well connected all pins are connected to pins in arduino…
  2. no there is nothing shorting them between the two pads I have 20k of resistence, 10k of each one…

everything went well except when I came to this situation and realize that probably nobody has had this problem yet… >:(

Can you post a photograph of your shield?

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Sorry, I’m out of ideas :frowning:

It looks like it should work.

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A picture of the bottom side also?

Weird problem.

I'm going to ask this even though it'll probably make me look stupid. Just on the slim chance it helps.

Is that a full pin gap you've left between the 5v and the Gnd?

thats a cool case you got it in. homemade?

no, there is no pin gap, the cross that you see between pin 5V and GND is the cross that program have to move the component of pins that correspond to pins of arduino…

And yes its homemade, is that why I don’t know if I need some “extra”, “different” connection between pins to make the arduino work with a shield …or if it is because resisters are very low…

Check the arduino voltage when it is plugged in.

Have you done this yet?

also post a pic of the bottom.

Two things (not sure if they'll help though):

  1. can you take a picture of the underside of the shield
  2. those look like 4 barrel connectors at the end that look like you have the wires connected to the outer barrell and not the center pin, are they wired together externally?

The problem with cross posting is that the thread is fragmented and you miss parts of the discussion.
See my reply at:-;num=1281363027;title=PostReply

yes the arduino has 5V when its plugged in, at soon I will post a foto from de bottom of the board, i don't believe that so much because the pads was all well connected, they are not shorting nothing, the board has only one layer of varnish to protect the circuits and can not see very well the bottom but I make the possible to see something....

The point is that what you are doing should not happen. You have done something wrong. What you are trying to do is correct you just have not implemented it like you think you have.

Due to your fault you see there are a limited number of things that can go wrong, very little should affect the USB chip apart from the 5V power supply and the 3v3 supply.

You have to keep looking with a voltmeter to find where you have gone wrong.