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by gainestr on Thu Oct 18, 2012 5:25 pm

After purchasing the Pi Cobbler (PID: 914) I have noticed that it has a lot of noise in the cable. I am not able to get good input readings when using the Pi Cobbler. My PIR sensor (PID: 189) that I have purchased from you does not register effectively when using the cobbler. If I touch the wires with my finger, it will trip my input reading. I believe that the cable is not properly shielded and when viewing the all I/O pins using a python script that I created, I can see that pins will jump from a high to low state on their own. When the cable is disconnected, everything reads fine. I have rechecked all of my solder joints and can not find anything even remotely close to being an issue. Again, I feel that it is a shielding issue. Any suggestions?
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by adafruit on Thu Oct 18, 2012 5:44 pm

do you have pullups installed?
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by gainestr on Thu Oct 18, 2012 10:59 pm

Yes, Pull up resisters are installed. I have even tried GPIO 8 (BCM 0) which has a 1K8 pull up on board. Even without anything plugged into my bread board except the Pi Cobbler, I encounter issues.
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by adafruit on Fri Oct 19, 2012 12:18 pm

The cobbler is just wires - and we've never heard of this issue - it could be something with your wiring. Replacing the cobbler is unlikely to solve your problem :/
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by gainestr on Fri Oct 19, 2012 5:10 pm

Yea, I don't really think its the cobbler myself. I think that its either a bad connection on one end of the cable or a short in the cable itself. There is definitely some bleed over in the cable, that is for sure. I guess I'll have to look for a higher quality cable then the one you provide. But I guess that if I'm the only one with this issue then it must be an anomaly.
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by gainestr on Tue Oct 23, 2012 5:38 pm

Looks like I'm not the only one with cable issues after all.
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by flaneur on Mon Nov 05, 2012 10:41 pm

I'm also having a confusing time with my cable. I don't think it's the soldering of the cobbler piece itself. I've found I have to touch the ribbon to get it to give non-zero values back to the Python GPIO example. At first I thought that the Cobbler wasn't seated correctly in the breadboard, or the ribbon wasn't seated correctly in the Cobbler or Pi itself, but I'm pretty confident this isn't the case.

Even the gentlest of touches of the ribbon can provoke it to produce non-zero values, but moving the cable in various ways by holding the Pi with one hand and the breadboard with the other will not produce a value.
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by adafruit on Tue Nov 06, 2012 10:06 am

post up a clear photo of the project & wiring - we can take a look
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