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I am confused with the word : channel

I see some of you with 80 000 lights and 16 channels, ???

I understood that a string of 50 pixels represented 150 channels,  Am I confused ?

 

Yet a controller seem to be limited somehow to 512 channels ?

 

please help unconfuse me ....

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12 minutes ago, grouptcl said:

I am confused with the word : channel

I see some of you with 80 000 lights and 16 channels, ???

I understood that a string of 50 pixels represented 150 channels,  Am I confused ?

 

Yet a controller seem to be limited somehow to 512 channels ?

 

please help unconfuse me ....

512 is the number of controller IDs, not channels. The number of ID for dumb, is 1 per controller. The number for Smart is the number of PORTS (a Pixie 2 uses 2, a Pixie 16 uses up 16. You only set the first on for the board. It inherits the next N as needed)

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An AC controller for regular lights has 16 channels. That means you can control 16 sets of regular lights independently of each other. A set of lights can be any number of bulbs, up to the amperage limit of that channel. With led strings that could be thousands of bulbs per channel but of course they will all be doing the same thing.

A pixel is really three bulbs in one. A red, green and blue led which can produce any color by mixing the three channels.

If this is a smart pixel it also has a chip inside which allows direct addressing of the 3 channels allowing the software to control the color.

If there are 100  pixels in the string (there can be any number within limits) there would be 300 channels to control from the software, and any pixel could be any color you like.

In order to organize the large number of channels, we separate them into DMX universes, 1 universe is 512 channels

That's probably enough for starters.

Edited by PhilMassey
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In my classes I always describe 'channel' as being the 'smallest unit you can control'.  Notice there is no mention of color, or even POINTS OF LIGHT (since channels can control other things like Servos, etc).

So if you have a bush that has 2 different colors of regular lights on it, and you connect it so that each single color can be controlled.  THAT is the channel: Bush, Blue or Bush, Red.  1 channel controls 1 color for that entire bush.  If you want the bush blue, turn on the blue channel for it.  If you want it blue and red, turn on both.  If you have another bush and put 2 different channels on it each of those 2 bushes can blue, red or a combination at any time.  2 bushes times 2 colors = 4 channels.

RGB:  RGB just refers to the mixing of different amounts of those 3 colors to make ANY solid color.  Since we need to control the amount of each of those colors, we need 3 channels:  One for each.

Now you have the same bush, but you instead use DUMB RGB.  The smallest unit you can control is still a channel - blue or red or green.  However because those 3 LEDs are in the same lens, they mix and now you can have any color.  We sometimes call that an RGB channel but that is not correct.  It's really an RGB group.  But at the end of the day, you are still only going to control 'the bush'.  Also remember that RGB has absolutely nothing to do with the concept of 'PIXEL'.  RGB just tells you that whatever it is, that particular thing can be any color at any time.

Pixel:  Pixels are individual bulbs on a single string that can be controlled. TECHNICALLY nothing says they have to be RGB (but 99.995% are -- keep reading).  For now lets just say they are ONE color, AND NOT RGB.  That is perfectly legal!  Older pixel technology was single color (white light) ONLY.

So in this case the smallest unit you can control is 'the pixel'.  It will either be ON or off.  The number of pixels is the number of channels required:  50 pixels = 50 channels (remember we are NOT RGB!).  The smallest thing you can control is a single point of light.

Pixel + RGB = SMART pixels: BUUUUUT.... As I said, nearly ALL pixels are also RGB.  That means that where before we used 1 channel to control a pixel, now we need to use  3.  Remember?  We can control the color, and controlling color requires THREE inputs:  the amount of Red, Green, and Blue to mix.  If you want the 5th pixel to be red, you turn on THAT channel.  If you want the 23rd pixel to be BLUE, turn on that channel....

... and again, because these are RGB bulbs (remember:  RGB is nothing more than 3 LEDs in the same lens that can be mixed) you can use the 3 channels assigned to that pixel to make whatever color you want.

RGB channel? :So why do we sometimes (most of the time) call it an RGB channel instead of an RGB group?  We probably shouldn't, but we do.  It goes back to the notion of 'Smallest unit you can control'.  In your mind, you set a color to an RGB 'thing'.  'Color' in this case is singular - you wouldn't consider programming an RGB item in any other way.  TECHNICALLY however, that color is composed of the mix of those 3 different components.  Each of those components is a channel.

UNIT:  So, as you can see with high channel count devices, things can get out of hand in a hurry.  That is where the notion in the LOR world of UNIT comes into play.  Think of a Unit as being the smallest DEVICE that you are addressing.  Some controllers are single devices, like our 16 channel AC controllers.  Other controllers however have MULTIPLE devices, for example our PIXIE controllers.  A Pixie 8 is a single board that houses EIGHT devices.  In this case, each device is an output port on the Pixie.  

Lets examine that a little more and show you why we do it that way.  A Pixie 8 can have a maximum of 1,360 RGB pixels attached (There are 8 ports and each port can run 170 RGB pixels.  8*170).  And don't forget that each of those pixels, because they are RGB, require 3 channels.  That means that one board controls 4,080 channels.  If you have 5 of them, your channels would be numbered from 1 to 20,400.  So quick! Tell me which is the RED channel on board #3, the 5th port, 23rd pixel?  Without a lot of math, you can't.

Let's make that easier by giving each port a unique, separate ID.

So board 1 get's IDs 1-8 (we set the board to starting address 1 and it consumes 8 UNIT IDs).  We set board #2 to 11, board #3 to 21, board 4 to 31, and board 5 to 41.  (yes, we are skipping some numbers)

So board 3 starts at 31.  Port 5 is ... 35 obviously.  That's easy enough.  Now we need the 23rd pixel.  When you look at your sequence or preview, you'll can quickly find unit 35, pixel 23.  If you really need to know, expand pixel 23 and find it's channels 67,68,69.  U:35,C:67 is much easier to remember and find than 4997!

Address:  You need to know that an 'address' in the LOR world is the complete identifier to a particular 'smallest unit you can control'.  An address consists of THREE parts:  We've talked about channels being the most basic unit.  From there channels are grouped into Units ( also called devices or controllers).  We also allow you to group units, and a group of units is called a NETWORK.

NETWORK:  Just to completely round out this discussion of 'addressing' lets talk about Networks. 

Your home address consists of The State and City (Network), the Street (Unit), and finally the numeric address (channel).  LOR networks are the same.  You can have up to 16 different networks, and they are named REGular, AUX A, AUX B...,AUX O.  Many people only have a single network, so we tend to ignore it when we talk about addresses.  We say things like U:30, C:15 where we just assume the network is REGular.  

If however you have more than 1 network, you must identify it.  REG, U:30, C:15 is a different address than AUX A,U:30,C:15.  There are many different reasons to use multiple networks, but typically it is due to the upper limit of channels allowed on a single network.

 

So now you should have a firmer understanding of:

Addressing:

  • Channels (also called 'Circuits) - the base of all addressing
  • Units (also called 'Devices' or 'Controllers') - collections of channels
  • Networks - collections of units.

Pixels

  • Individual points of lights that can be individually controlled on a single string
  • May or may NOT (but almost always are) RGB

RGB

  • Talks only of mixing different amounts of Red, Green and Blue to form any color. 
  • Says nothing about if lights on a string are individually controllable or not
  • Almost ALWAYS pixels (also called SMART strings) are RGB, but there is NO requirement.  RGB and Pixel are separate concepts
  • Some strings/ribbons are DUMB.  You can control the color, but not WHICH point of light is on.  They are all the same color.

 

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@DevMike
Thanks for the thourough explanations !
I will run to the computer and try a layout to sink it all in.  I noticed however that you skipped numbers (your emphasis),I had noticed that the system did that also, any particular reason for the skip ?

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Let's see if I understood this properly:
If I was to use a Pixie8to create a billboard I would do this ?:

Create a prop called Pixie8
Let it know there are 8 strings; say folded
It would attribute Unit ID (per the maximum 512 channels available)

I am presume this iis correrct, if so then how do I attribute these ID'S to the right spotr(connector) on that card once hooking it up the the computer ?  I tought each card (controller) couls only have one ID ?

Did I go astray and if so where?

Please advise

Pixie 8.JPG

Edited by grouptcl
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21 minutes ago, grouptcl said:

Let's see if I understood this properly:
If I was to use a Pixie8to create a billboard I would do this ?:

Create a prop called Pixie8
Let it know there are 8 strings; say folded
It would attribute Unit ID (per the maximum 512 channels available)

I am presume this iis correrct, if so then how do I attribute these ID'S to the right spotr(connector) on that card once hooking it up the the computer ?  I tought each card (controller) couls only have one ID ?

Did I go astray and if so where?

Please advise

Pixie 8.JPG

Don't know about S5 however pixie controllers will use the # of the pixie. A pixie2 = 2 Unit ID.s, Pixie4 =4 Unit IDs and so on and so forth

JR

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For Pixies: Each unit ID (port) supports  UP TO 100 RGB nodes or 300 channels

You will use 8 Unit ID's. 1 per port (not under your control) The reason the tool let you do what you did, was to allow shorter strings segments to be set up/fold., not go over 300 channels

So my numbers are 2400 channels max for a Pixie8

You may not have more than 64 Pixie 8's in a LOR system (your 512 number). Actually, I think there are other restrictions on that 512 You can't use 0, and some are reserved

 

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@TheDucks 

ok so if I get this right, we are limited to 512 channels (circuits) per each ID (port) ? 

So to get the right limit picture we can play with:

16 Networks
512 channels per ID
So far that is 8192 max controllable pixels

What is the limit on ID's within a network ?

So the question is: How many individual pixels can one control with LOR ?


 

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4 hours ago, grouptcl said:

@TheDucks 

ok so if I get this right, we are limited to 512 channels (circuits) per each ID (port) ? 

So to get the right limit picture we can play with:

16 Networks
512 channels per ID
So far that is 8192 max controllable pixels

What is the limit on ID's within a network ?

So the question is: How many individual pixels can one control with LOR ?


 

Why are you stuck on 512??  (someone else needs to answer if you are running in DMX mode. I only do LOR mode)

The ONLY place I see that number (chart for setting ID switches) is for LOR ID's

Not for Channels. Not for Ports (directly. You can't assign ID 512 to any Pixie, because there is nothing available above that to inherit for the rest of the ports on the board)

Look in the back of the various manuals for EACH KIND of devices limits. There are many. Some just require creative powering (injection).

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Personally I am not stuck on 512, it keeps popping up in the explanations, I will wait for more infos when the cards arrives next week, that might be better

Thanks guys for the infos so far

 

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12 minutes ago, grouptcl said:

Personally I am not stuck on 512, it keeps popping up in the explanations, I will wait for more infos when the cards arrives next week, that might be better

Thanks guys for the infos so far

 

Much easier to keep your pixies as just straight strings. In other words, no folds or zig zags.

K.I.S.S. is the best method. Run LOR networks especially until you get more familiar with pixels.

I see you are using more than 170 pixels on some rows. The pixies cannot go above 170, unless there has been a firmware update I am not aware of. Even with PI.

I run 12-13 LOR networks without fail. I had 14 networks set up last year but wanted to leave one open so I consolidated and removed a couple props.

Every now and then I do have a hiccup mainly because of something I forgot to uncheck from the previous year. Scheduler over lap last year but it was an easy fix once I realized my mistake.

JR

Edited by dibblejr
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11 hours ago, TheDucks said:

For Pixies: Each unit ID (port) supports  UP TO 100 RGB nodes or 300 channels

You will use 8 Unit ID's. 1 per port (not under your control) The reason the tool let you do what you did, was to allow shorter strings segments to be set up/fold., not go over 300 channels

So my numbers are 2400 channels max for a Pixie8

You may not have more than 64 Pixie 8's in a LOR system (your 512 number). Actually, I think there are other restrictions on that 512 You can't use 0, and some are reserved

 

Actually pixies will support up to 170 pixels each.

My video under General Hardware explains how to set them up.

JR

Edited by dibblejr
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LOR Controllers, along with DMX universes have a hard cap on the channel number of 512.  

The issue you are having is that you are 'packing pixels'.  You should not 'pixel pack' (IE, use EVERY address available to you) as it just leads to this kind of frustration - EVEN IN DMX mode (which you are not using if you have Pixies).  Early pixel controllers FORCED you to pixel pack.  Newer ones (like ours) do not.

Let's look at an example of a theoretical pixel controller.  This pixel controller has 8 ports, and each port can support up to 170 pixels per port.  To this pixel controller you connect only 100 pixels per port.

Not Pixel Packing:
Each string starts at it's own network identifier (in the case of LOR, that would be NET and UNIT, in E1.31 it would be universe).  Pixels on that port are numbered from 1-100, and therefore consume 300 channels (1-300).  212 of the possible 512 channel IDs will simply not be used (301-512). 

Pixel Packing
Pixie controllers do not allow you to pixel pack.  For E1.31 controllers (DMX over IP) the first string starts at the network identifier (Universe).  Pixels on that first port are numbered 1-100 and consume channels 1-300.  The SECOND string on the SECOND port however continues from the first.  The first 70 pixels will have the SAME network identifier (Universe) as the first string.  The first 70 pixels will be numbered from 101-170, and will consume channels 301-510.  But what about the last 30 pixels?  Those will move to the NEXT network identifier (universe), and will start over with pixel 1-30 (channels 1-90) - your network ID just changed in the middle of a string.  You next full string will be on the next port but start at that network identifier, and the first pixel is number 31 and will run through 130.  The next string is on the next physical port, starts at pixel 131.  It will run for 40 pixels at which time the network identifier changes again.  Are you confused?  Yes you are.

Remember what I said about being able to QUICKLY identify a particular pixels address correctly?  Not packing makes it SUPER easy.  Packing on the other hand requires that you know how to do a lot of math.

The ONLY advantage pixel packing has is that it allows you to use LESS network identifiers (Network and Unit ID).  There is no reason for that - long before you run out of network identifiers, you'll run out of bandwidth.

So REGARDLESS of what protocol you are using (LOR or E1.31), DON'T PIXEL PACK.  It is OK TO WASTE those channel IDs.

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