problem with led pixels

Hi,

i bought a strand of 50 led pixels claimed to be using the ws2801 chip (bought it from a supplier in "alibaba").

when i tested the strand with the adalight processing and arduino code, it shows random colors (all 50 leds are working) regardless of the code...

i suspected that it uses another chip, so i tried a code i used for lpd6803 chip, and it works perfectly...

the only problem is that the chip in the strand has 14 "legs" and i know that lpd6803 has 16 "legs"...

i'm confused...

did anyone ever met such a problem ?

is there a way i can tell for sure which chip is in the strand ?

thanx
ohad

just wanted to clarify, the i have another ws2801 strand (rectangular containing 4 leds each) that works perfectly so the codes i'm using is ok.

It sounds like you took your risks on an unknown product, discovered it didn't work the way you thought, and figured out a complete workaround solution. Is there still a problem?

this sounds stupid, but make sure both your grounds are connected to the arduino. The same thing happened to me when I got mine. Where did you get yours from? I too, went to alibaba... I'd be interested to know.

Also, if you post a picture of your pixels, I can confirm that they are/are not using the ws2801 chip!

Hi!!

There are some libraries that work with many RGB PWM drivers, such as WS2801 and LPD6803.

For example:
http://code.google.com/p/fastspi/

Use that library and you do need to know which strand (driver) type are using, just need to know your strand has to have one of these drivers:

  • 595 style shift registers
  • hl1606 based led strips
  • lpd6803 based led pixels
  • tm1809 based led strips
  • tm1804 based pixels
  • ws2801 based led strips and pixels
  • lpd8806 based led strips

I also made the adalight project, but I bought the strand from adafruit, just to avoid the problems you are having

Cheers!!

I should point out that many of those driver chips that are listed in the FastSPI library will also have a different name. For example, the LPD1101 is the next generation for the LPD6803, so you can use the LPD6803 configuration in FastSPI to drive the string just the same. You can even drive a WS2803 (18 channels) with it using the WS2801 (3 channels) driver.