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how do i attach a pressure mat to the analog inputs without the mat disconnecting the whole board when no pressure is on it?

????
:-/
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can you give a datasheet? or any type of indication what our talking about? more people might help if you get specific...
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yes, sorry about that.

have a pressure mat connected to the analog inputs of the arduino, (5v, grnd, and 1).
when ever there is no pressure on the mat it turns the whole arduino off, and says on my computer screen that the usb device was removed badly.
How do i avoid this, as I am trying to trigger coding when someone stands on the mat.

hope that makes more sense
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this can happen if you draw more current than the Arduino board can handle, are you shure you hooked the mat up correctly ?`

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How much current does the pressure mat use and does it change with pressure?

Can you try to power the mat from another power source to see if that works ok?

edit: mikmo beat me to it
« Last Edit: February 28, 2008, 02:34:12 pm by mem » Logged

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Is the mat shorting your Arduino out?  It could be that it has near zero resistance when there is no pressure.  Try putting a resistor (say 4.7k) in series with it.
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mikmo&mem - the mat is a four contact pressure mat. it's pressure can either be 1 - 0 , or 1.0 - 0.0, and it can't be powered.

maverick - that is what it is doing, i will try it with the resitor, thank you . I hope it works......


beginner at electronics, hence the lack of jargon.
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do you have a link to a datasheet for the mat ?

Theres a few things i would like to understand :-)

Is it working like a switch or like a variable resistor ?



« Last Edit: February 29, 2008, 08:01:18 am by MikMo » Logged

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like a switch, but i can get it to not disconnect with the whole computer when it is just s=connected to the arduino software, but when connected to other software, e.g.max or SC it disconnects the whole board from the computer

sorry don't know anything else about the mat
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mikmo,

this is the mat, not much detail, maplins is not the best with that

http://www.maplin.co.uk/Module.aspx?ModuleNo=3092&criteria=pressure%20mat&doy=1m3
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That link says the mat is has two contacts that are a normally open switch, and two anti-tamper contacts. Think of the mat as a switch and have a look at the Arduino digital input tutorials for guidance on sketch code and connecting the mat's two switch terminals. You can probably ignore the anti-tamper contacts for your application.
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As mem says, this is basically 4 switches. They should be connected to digital pins on the Arduino NOT analog pins.

Se the switc sample in the palyground for how to use pullup resisors and connec everything.
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thank you, will try that
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thanks, it works perfectly  smiley-grin
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