Christmas lights version 3
the rise of the RGB pixel
For nearly a century our parents and grandparents have been hanging lights on trees, houses and yards – and, for nearly that entire time, they were just static, sans maybe a blinking bulb or two – this was Christmas Lights Version 1.0. Then, in the late 90’s, a movement started to sequence lights to music using personal computers. Since the late 90’s and up through 2010, that same basic system of controlling lights has prevailed – a personal computer with software, that controls a box, that turns a typical strand of incandescent or LED (Light Emitting Diodes) lights on and off – this is Christmas Lights Version 2.0.
What drove the move from version 1 to version 2 of Christmas lighting was the rise of cheap personal computers, the availability of low cost microprocessors used in lighting controllers and the primary component that made it all possible – the rise of the Internet and its ability to easily share ideas and designs of controllers and software. While the interfaces for controlling lighting controllers used in version 2 changed from parallel ports to the RS-485 network used by DMX (Digital MultipleXing), Light-O-Rama, Animated Lighting, Renard and others today, the same basic design didn’t change – a controller that could vary the intensity of a string of, typically, AC (Alternating Current) powered lights. About half-way through the decade, as displays became more complex and the channel count rose from dozens to hundreds, people started adding multiple colors of strings on different channels so that they could, for example, turn a mini-tree white, blue, red or green instead of just a single color; this has now become quite common place in displays today. While adding additional strings did allow additional colors, what it didn’t allow was for them to be mixed to form secondary colors such as pink, purple, yellow or orange and still the most granular control that could be applied was to an entire string of lights at a time.
In 2008 and 2009, the appearance of color mixing RGB (Red Green Blue) lights, primarily in the form of flood and spot lights made their appearance. Then in 2008 d-Light introduced their RGB FireFli pixel string and 2009 saw the introduction of the Cosmic Color Ribbon (CCR) from Light-O-Rama, another RGB pixel device. While a small number of these RGB flood lights and RGB strings were used in displays (relative to ‘traditional’ A/C controllers), they lacked a critical component necessary in the most popular sequencing application, Light-O-Rama S2 software suite– the ability to easily mix those RGB colors natively. So the ability to really take advantage of those devices vast color range was severely limited. Another serious limitation for people with the FireFli, and in particular the CCR, was that they now had several hundred channels to sequence since a CCR “strip” is comprised of 150 channels for every 16 feet of strip. The question became – how do you control such a granular level of lights? The short story was – you generally didn’t, since it was just exceedingly complex to do so by hand using LOR S2. So, the FireFli and the CCR were often just used in their primary colors of red, green and blue and turned on and off in “sections” or controlled via built-in macros (such as found in the CCR.)
Looking at this problem in early 2010 it was obvious to me that while there were hints of some really interesting RGB hardware coming down the road and we needed much better software to be able to sequence this new type of hardware. So in the Spring of 2010, I wrote an article titled “Death of the Grid” in PlanetChristmas magazine, in which it laid out what I thought would be solutions to the software sequencing limitations we had, up until that time, with this new breed of RGB and pixel hardware. It was shortly thereafter that David Johnson, developer of LightShow Pro, introduced version 1.7 of his application that was the first major jump forward in the ability to sequence not only RGB devices, which the application was doing previously, but more importantly it had the ability to “auto sequence” a majority of a sequence using simple video files – it basically allowed you to turn your display into a huge video screen using its new Video Transition feature. The first major piece in the puzzle had been solved – it was now possible to sequence thousands of channels with the same ease as a hundred channels, with more complexity and detail than could ever be accomplished by hand sequencing or using built-in hardware macros.
Now before moving on, it’s best to start with a few descriptions of some hardware items. While these terms are in flux at the moment since they don’t have a single vendor or trade name, they are commonly used names for these items.
During the spring of 2010 there had been two developments in RGB lights – the discovery of a very inexpensive $7 three channel DMX controller and the development of the Tiger DMX, a high density 120 channel DC controllers by Phil of Aussie Christmas Lighting. The $7 DMX controller allowed for a decentralized method of putting an RGB controller directly into an element such as a mini-tree, star, snowflake or other discrete display element and at that price range allowed for a lot of RGB channels to be exploited in an expensive manner. The Tiger DMX board allowed centralized elements such as highly complex mini-trees with 120 channels per tree, mega-trees, matrix displays and other high channel count item where the wiring was centralized.
What become obvious with the 120 channel controller was that wiring 240 individual parallel wires was going to get very messy and complex when scaled up, so another solution was necessary. That solution was to focus on a serial based wiring system like that used in the Light-O-Rama CCR and the d-Light FireFli. The problem was that all the inexpensive Chinese pixels, be it nodes, strip or modules used special chips and proprietary controllers. So, in the summer of 2010, Phil and Tabor of Aussie Christmas Lighting started work on decoding the protocols used by commercially available pixel chips (such as the 6803 and 2801) and out of that work resulted the TP3244 – a board which provided an interface between the lighting protocol DMX and the proprietary protocol used by the pixel chips – it was now possible to cheaply and easily control all different kinds of RGB pixels at a cost that was up to 60% cheaper than commercially available solutions.
This creates a real problem – now it is fairly reasonable that even in a modest display, it would require thousands of channels to run the display since each pixel requires three channels. With DMX limited to 512 channels (Light-O-Rama’s protocol varies but ranges from 500 to 1,000 channels per network) per “dongle,” it would require numerous physical dongles – so how do you get that many channels and their data out of the sequencing software into lots of RGB pixel based devices? Well it turns out that someone else was already thinking of this same problem – Ed Bryson of www.j1sys.com. Ed could see that as this new generation of controllers was being developed, there would be a need for extremely high channel counts and so he got started designing a product to do just that.
Ed developed the EtherConGateway which took a single, high bandwidth, Ethernet signal and then split it into eight different “slaves” or what most people would call dongles or RS485 adapters. This then allowed you to have 4,096 channels from a single board. While this may sound like a lot of channels when so many displays, even today, are under 200 channels, these levels of channels are required to support a typical pixel based display. The protocol that the EtherConGateway was written to support is based off an open standard called E1.31 or “Streaming ACN” (Architecture for Control Networks ) which was originally developed for the professional lighting industry. This protocol was when added into LightShow Pro version 1.8 and Vixen, a free sequencing application. It was then that all the parts necessary to support large, complex, multi-thousands pixel displays were in place.
So why would you want RGB pixels? There are a variety of reasons why to consider a move toward RGB pixels over standard light strings:
Flexibility – Imagine putting up lights on your house for Halloween – already you’ve got orange, purple and green covered and it’s one less thing you’ll need to put up for your Christmas display because those same lights also do blue, green, white and red. Want to do a July 4th or Valentine ’s Day display – no problem, RGB pixels can handle that also.
Value – While the upfront costs for pixels and the controllers to run them are slightly higher than a traditional AC controller with traditional LED strings, when you consider that within a single string of pixels you have nearly every color you could need for a display, something that isn’t even possible with traditional methods, you end up with better overall value.
Size/Weight – Unlike “super strings” comprised of several different traditional LED strings, pixels are typically only comprised of three to four 18-24 gauge wires. This allows them to be lighter, easing requirements for substrates that “super strings” would normally be attached to. So instead of requiring a large PVC pipe frame, just simple light weight plastic sheets could be used as the mounting surface. Pixels are lighter which makes for easier storage and handling – real handy when you are on top of a tall ladder.
Granular Control – Pixels, while they vary in size, generally offer the ability to control individual groups of LEDs in sections as small as a few inches. Imagine a spiral mega-tree, but instead of building it with a physical spiral of the light strings around the tree, which is fairly complex, you just build it in the traditional vertical, top-to-bottom vertical fashion, and then instead create the spiral effects in software. The granular control of pixels also allows you to do very smooth fades of color across a large area. Imagine that you have pixel strips or pixel modules lining your gutters, roof lines and windows – creating a smooth red to green horizontal transition over the entire house only takes a few seconds and results in an ultra-smooth transition. Compare this with traditional strings in which only “blocks” of lights, say the right side of the house or the left window could be controlled individually – where pixels would allow you to fade sections as small as a few inches.
No Fading Issues – As all RGB pixels are run from DC (Direct Current) power, they do not suffer issues with improper fading, the need for “snubbers” or parts of the string that can catch on fire as can occur in LED light strings driven from high voltage AC power.
While RGB pixels have many advantages, they are not perfect and a few things to be aware of are:
No Standard Interconnect – Standard Christmas lights use the standard AC (Alternating Current) plug for power connections (in the US.) This means that off-the-shelf parts and interconnects can be used to connect the display together. Currently with pixels, there is no standard connector used to provide signal and power to each string. A common solution is CAT5 (Category 5) but there is no standard around its use.
Often a DIY Solution – Only two vendors offer nearly complete RGB pixel devices to the residential lighting community and those still require the end user to weatherproof the control box and power supply. All other currently announced solutions for pixels are DIY only, in varying levels – from completely assembled boards to solder together solutions.
Requires a Power Supply – As pixels are driven by DC, this means that a DC power supply must be used to drive them. There are a variety of solutions for this – inexpensive waterproof DC power supplies, centralizing the power but they all do require the use of a separate power supply not required by “standard” strings.
More Complexity – Pixels are just inherently more technically complex to deploy as they involve the use of more channels, they have more options as to physical form factor, color options, diffusion and power. Additionally, as pixels are “new”, they involve a learning curve over standard lights and controllers.
Better Software – To get the absolute most value from pixels, new software will need to be developed that is completely different from the grid-based software we use today.
So, what’s ahead for Christmas Lights 3.0? As of late 2010, there are already a number of new announcements for pixel controllers from a variety of DIY sites and rumors that additional commercial vendors will be offering inexpensive pixel based solutions in the coming year. The upcoming year will also see many improvements in quality, standardization and huge improvements in sequencing software that should make incorporating RGB pixels into a display easier and less expensive. So 2011 is really looking to be the year of the RGB Pixel and the start of an entirely new level of Christmas displays never seen before!
This article was included in the December 2010 issue of PlanetChristmas Magazine.
By David Moore