LPD8806 strandtest only first 4 LEDS working

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bullapse
 
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LPD8806 strandtest only first 4 LEDS working

Post by bullapse »

Hi,

I think that I am having the same problem as the post herehttp://forums.adafruit.com/viewtopic.ph ... st#p164015

I ordered 2m of LPD8806 LED strips. I have had trouble getting them to work. Today I worked on troubleshooting the problem. I followed the directions for troubleshooting using this tutorial to see if I could get the strips to work without any luck. https://learn.adafruit.com/digital-led- ... leshooting

I followed everything to a T, but couldn't get the strips to work. The problem is that Only the first few LEDs respond. The rest remain off or flicker randomly, so I followed the suggestions in the guide of the link above. I tried squeezing the strip to find a bad connection, but that didn't work. I ended up cutting off the first two LEDs to see if it was just a bad beginning of the strip, but that didn't work either. I then found out that after the (now) 4th LED, the connection is bad, but I couldn't get it to work unless I held the lead wires directly to the connection after the 4th LED, then the next 18 LEDS would light up to the desired color. (I am using the Adruino UNO Libraries listed in this tutorial btw) I could never get the LED strip to react in the right way. Also the (now) 3rd led is showing purple when the other 3 LEDs that work are showing Blue where blue is correct.

I think that I just got a bad 2m of LED strip.
I will attach pictures of the connections to the LED strip and the UNO
IMG_20140908_142017.jpg
IMG_20140908_142017.jpg (437.53 KiB) Viewed 156 times
IMG_20140908_142113.jpg
IMG_20140908_142113.jpg (393.09 KiB) Viewed 156 times
IMG_20140908_142152.jpg
IMG_20140908_142152.jpg (436.68 KiB) Viewed 156 times

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pburgess
 
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Re: LPD8806 strandtest only first 4 LEDS working

Post by pburgess »

Agreed, I think you got a bum piece of strip. Email [email protected] with your order # and a link to this thread, we'll issue a replacement.

I don't think it's the cause of the problem, but just a tip: I'd suggest pinching two wires in the ground side of the DC jack adapter...run one directly to the strip, the other to the Arduino. The PCB traces on the Arduino might not be adequate for the amount of current, so using it as a ground passthrough isn't always a good idea.

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