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Connecting pixels


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I just got my first smart pixels and controller. The controller is a DMX to WS2801, and the pixels are WS2801, but I am unsure of where the wires go.

The pixels have 5 wires. +5v, Ground, Clock, Data, and a second ground.

I have looked at the Ebay page and it says the controller can work at 5v, but I only have female jumpers. Will a loop of wire do the job of a jumper?


The controller has Clock, +12v and GND, as well as SPD. Is SPD for the data connection?

I think I know, but am not 100% about where the wires go.

Does anybody know if the wire will work?

Edited by EmmienLightFan
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If your pixels are 5 volts, DO NOT connect them to 12 volt power - you will quite likely let the magic smoke out.

And like Kevin said, post pictures and details of what you have (links to the correct page on the site where you purchased them is really good).

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I connected them with another power supply. They did nothing at first, not even in the demo mode. The last light (Near the female connection) comes on white, and once, I disconnected the Data and connected it again and the last light went blue. I did this again and it went a brighter blue.

The cable comes out of a RS485 adapter, and is connected like this:

Blue +

Blue Stripe -

Green Gnd (Tried with and without)


The pixels have writting on inside. The +5v and the Gnd is correct. I cannot read the other words, but from what I read online, I think white is clock and green is data. The words inside the silicon look like CO and Do, CC is above the green and Do above the white. Any ideas as to what it says/means?


The light on the board goes orange/yellow when dipswitch 10 is on. Without it being on, the light is a dimmer yellow and flickers quickly. I am using a 5v 2.6a power supply. 


If I wiggle the wires after the last pixel, the last one changes to different colors/off. There is a video below of this.

Since taking the video below, I have removed the end to see if there was a bad connection inside. They still do the same. No wires are touching, just moving them makes it change.


The If Pwr 5v jumper has solder in between, as there are no pins to put jumpers on. There is a jumper with pins that came with it. On the Ebay page it says "If closed 120 ohm resistor connected between D+ and D-. Should this be there? And should it matter? The diagram they give for that is included below.

If you know anything that could possible help or solve this problem, please please say. I have been waiting for a while now and really want to see them working. I have wanted to get into smart lights for a while, and I thought it would be simple to setup.

Links to photos, videos, diagrams and Ebay pages are below.


More links in the links document,

Thanks very much.

Edited by EmmienLightFan
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The first thing you will want to do is get the controller card lighting the pixels in demo mode.  Don't worry at all about getting your computer to send data to the controller via the DMX leads.  Here are a couple things you need to check on.


1)  Do you know FOR SURE what wire color is what signal on the pixels?  Don't assume anything.  These most likely come from China and there is NO standard for color code.  You may be able to see labeling on the pixels themselves from which you can determine the color code, or the vendor may supply the information (I could not see any labels on the pixels in your pictures and the ebay listing did not state it).  I see that the pixels have Red, Green, Blue, and White wires and you have them hooked up as follows (based on the pinout of the controller board):

   Red = Power

   White = Clock

   Green = Data

   Blue = Ground

That may well be right, but you CAN NOT assume that. 


2)  There does need to be either a jumper or solder blob between the "If 5V jumper here" traces.  What this most likely does is bypass the internal voltage regulator that feeds power to the controller itself.  The controller itself most likely runs on 5V and if you are feeding the board with 12V, there is an on-board regulator that that drops it down to 5V for the controller board power.  The other possibility BTW is that the controller board runs on a lower voltage (most likely about 3.5V) and there is an on board regulator that takes whatever comes in and drops it down to the required voltage.  There could be a voltage dropping resistor that drops some of that voltage that is bypassed when the jumper is installed.


3)  For the time being, you can ignore the reference to the 120 ohm resistor across the DMX line.


4)  From the really crappy documentation, it looks like if you set dip switch 10 to on, it will play one of the pre-programmed test sequences.  Varying the settings of switches 1 - 5 will change which test pattern.  If you can't get that to work, then you need to resolve the problem before even trying to send DMX signals to the controller.  In your pictures, you have switches 1, 6, and 10 turned on.  That should have test mode on with pattern 1, and switch 6 really should be off as that switch is used only for increasing the test pattern speed.

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Could getting the data and clock wires the wrong way damage anything? Should I just swap it and test them? 

Yes, I tried it on Auto/demo.

In LeechburgLight's videos (A very similar controller, sold/made by the same person, which I have ordered for my next set of pixels) he has 10 on for DMX. Quite strange.

I have tried several modes. I do have a small solder blob between the holes of If Pwr 5v, as I said, and inside the pixels on the green circuit board, it says co and do. I don't know what this means, but as there are only two, if I can swap them without damaging anything, then that will show what they mean.

Thanks very much for the quick reply. 

Edited by EmmienLightFan
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Swapping clock and data should not damage anything.  Swapping power wrong with just about anything holds the potential of damage.  If you look carefully at the pixels there should be six connections - +5 voltage, ground, Data In (DI), Data Out(DO), Clock In (CI), and Clock Out (CO).  Within the string, Clock Out and Data Out on one pixel connects to Clock In and Data In.  Of course +5 voltage and ground daisy chain from pixel to pixel.  The Data In and Clock In of the first pixel should connect to the Data and Clock of the controller card.

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Do you have a voltmeter to confirm that you have not reversed the polarity from the power suppy to the controller?

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Thank you everybody who replied. I had then connected to the out. I had looked at the +5v solder and seen it was joined between in and out, so I thought they were all joined, and it wouldn't matter. I also had the wrong data and clock, and not enough solder on the if pwr 5v holes. Thank you very much. Next pixels and controllers are coming next week. Let's hope I don't have any problems this time.

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Let me explain a little what is going on with the pixels, and clarify a little of what I said in post #8.  In that earlier reply, I said that there were six connections, however there are eight wires connected to those six connections.  There is really a +5 Volts In and +5Volts Out, and also a Ground In and a Ground Out.  As you saw, the +5 In and +5 Out wires are either soldered to the same pad on the PC board, or there are are two pads for +5 that are connected in the PC board traces.  Similarly, the Ground In and Ground Out wires are either soldered to the same pad on the PC board, or there are are two pads for Ground that are connected in the PC board traces.   Therefore, the +5 Volts In and +5 Volts Out are solidly connected together, and similarly the Ground In and Ground Out are solidly connected together in each pixel.  Because there are tied together, we refer to them as power (+5 in this case) and Ground.  In fact, you can feed the power or ground from one end and the data from the other, or feed power and ground from both ends.  The latter is commonly done for injecting power into long strings.  On the other hand, Data and Clock MUST be connected in one direction and it must be the correct direction.  In each pixel, data and clock are received on the Data In and Clock In wires, and is processed by the chip inside the pixel.  The chip then generates a new data stream that is output on the Data Out and Clock Out wires and are passed to the next pixel.  If you have the Data and Clock reversed, you will be sending data into the output pins of the chip and it won't be able to process the data.  On many pixels there is an arrow printed that shows the data flow.  On some there are labels for DI and DO.  Note that some chip families have a data and clock signal (such as the 2801s that you have), and some only have data (such as the 2811s).

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