DMXpix Tutorial and Demonstration

This introductory document assumes familiarity with RC4 OneTouch, RC4MagicPC, and RC4 Series 3 Harmonized Design.  A more complete User Manual for the DMXpix will be available soon.  In the meantime, do not hesitate to contact RC4 Wireless for additional information and detail if needed – we are here to help.

Summary

The RC4Magic DMXpix is a very small wireless DMX-controlled driver for two separate strings of pixel LEDs, each string up to 500 pixels long.  It provides patent-pending RC4 ColorMatch for white-balance adjustment, and patent-pending RC4 Custom Pixel Profiles to create beautiful pixel effects utilizing up to 3000 output channels (RGB x 1000 pixels) while conserving the number of DMX control channels needed.

Many device parameters are accessible with a simple 3-button user interface.  It is easy to set the DMX starting address, string type, pixel color order, and white-balance for each string without the need for a computer or RDM controller.

Using RC4MagicPC software, all parameters for both drivers are displayed together on one screen.  Additional advanced features are provided, including parameters for grouping pixels to channels, setting how many channels will be used to control an entire string, and more – this is the core of RC4 Custom Pixel Profiles.

The DMXpix also provides a standard DMX data port, and an I2C interface for use with Arduino, Raspberry Pi, and other microcontrollers.   Because of the small size of the DMXpix (and other RC4Magic Series 3 devices), an adaptor cable brings DMX data out to a standard XLR connector.  (The XLR connector is comparable in size to an entire RC4 device!)

With everything configured as desired, control pixels from your DMX console in real time, limited only by your programming skills and imagination.

A concise outline of the DMXpix 3-button user-interface is provided at the end of this document.

 

Getting Started

This following tutorial demonstrates most features of the DMXpix with BETA firmware version 4.050.  It is intended to be used with a kit of sample equipment supplied by RC4 Wireless, which includes LED pixel strings, a DMXio transmitter, a DMXpix, a CodeLoader cable, and other items.

Future firmware updates are easily installed using the RC4Magic USB CodeLoader cable.  Adding new types of pixel strings and expanding the DMXpix feature-set are only a few clicks away.

 

Clear All Settings to Factory Defaults

In case your sample kit has been used by others and the current configuration is unknown, clear all internal settings.  You need two small button-pushing tools – bent paperclips are ideal – to operate the small recessed buttons.  As on most RC4 Series 3 devices, the Func button acts like a computer shift key.  Defaults are restored with Func-SetA:

With no pixel strings connected, apply power to the DMXpix.  Observe the start-up LED sequence and wait for it to complete, then:

  • Press and hold the Func button
  • Tap and release the SetA button (with Func still held down)
  • Release the Func button

LED indicators will blink several times.

Default settings are:

  • Both pixel drivers are configured for WS2812-based LED strings.
  • Both pixel drivers are set to start at DMX channel 1.
  • Pixels are 1:1 mapped to DMX channels: DMX channels 1/2/3 are RGB for pixel 1, channels 4/5/6 are RGB for pixel 2, and so on. (One universe supports 170 pixels using DMX channels 1 to 510.)
  • ColorMatch is not active. Color palettes will be displayed unmodified.

Disconnect power from the DMXpix and set up a DMX controller.

 

Setting Up a Wireless DMX Controller

The following steps require basic DMX data to be on the air for the DMXpix to receive.  This can be done with either a DMX console and a DMXio transmitter, or RC4MagicPC software with a USB dongle device and control from the RC4MagicPC Virtual TX tab.

Using a DMX Console and DMXio Transmitter

Connect the RC4Magic DMXio transmitter to a DMX controller with an XLR data cable, and be sure the transmitter and console are both powered on.  The DMXio with version 4.050 firmware or later will automatically detect the presence of DMX data and configure itself as a transmitter.

You must be able to set individual DMX channels to specific levels on your controller to proceed with the rest of this tutorial.

Using RC4MagicPC and the Virtual TX Tab

Previous experience with RC4MagicPC is assumed.  For additional information and assistance, contact RC4 Wireless. 

For DMXpix with firmware version 4.050, RC4MagicPC software version 3.14.6.4 BETA or later MUST be used.  Earlier versions are not aware of pixel devices.  If you do not have the installer for this software, please ask RC4 Wireless to provide it along with an RC4 Encrypted System ID file paired with the supplied sample equipment.

RC4MagicPC communicates with wireless devices using a hardware dongle connected to the host PC via USB.  As of firmware version 2.019, an RC4Magic Series 3 DMXio can be switched to Dongle Mode and connected to the PC through an RC4 CodeLoader cable.  As of firmware 4.050, almost all Series 3 devices are capable of Dongle Mode:

  • Plug the RC4 USB CodeLoader cable into your PC. If this is the first time using it, Windows Update will find and install the drivers (an Internet connection is required).  If you are using a Mac with Parallels or Bootcamp, it may be necessary to download drivers manually.  Contact RC4 Wireless for additional information.
  • Connect CodeLoader miniplug cable to the DMXio.
  • Apply power to the DMXio and wait for the start-up LED sequence to complete.
  • Press and hold the Func button for several seconds, until the DMXio LEDs begin chasing from left to right continuously. This indicates Dongle Mode.
  • Launch the RC4MagicPC software. The DMXio MUST be in Dongle Mode FIRST, before running the software.
  • Learning RC4 System IDs using the Public ID is no longer required. Find the supplied RC4 Encrypted ID file.  Click Load ID File, choose the file and click OK.  Your private system IDs are now available in your software.

Follow the 5 Easy Steps to Connect, as outlined on the opening screen of the software:  click the COM port for the dongle, click Use ID0, select RC4Magic (2.4GHz), and click the Device and IDs tab at the top of the page to proceed.

The Configuring RF progress box will briefly appear, and the software will switch to the Device and IDs tab.

RC4MagicPC must be running on the same RC4 System ID as the DMXpix.  With the DMXpix powered on, confirm that the blue RFcon indicator on both the dongle device at the PC and the remote DMXpix are blinking (not solidly on).  If either or both are not blinking, the wireless link has not been established.  Do not hesitate to contact RC4 Wireless for assistance.

Click the right-most tab in the software, Virtual TX.  You are now ready to experiment with the DMXpix.  The wireless data is equivalent to what would be coming from a DMX console plugged into a DMXio transmitter.

 

Setting up the DMXpix

The sample kit does not provide WS2812 pixel strings, which are the default type after restoring defaults. Now we will set up the DMXpix to work with the supplied APA102-based and LPD8806-based pixel strings.  If you have any other string types, like WS2811/WS2812, or WS2801, feel free to try them after working through this tutorial with the supplied strings.

With no power applied, plug the supplied APA102 pixel string into the DMXpix Pixel Driver A socket.  Plug the supplied LPD8806 string into Driver B.

These strings have 5V regulators in-line at the 4-pin header connector, so they are fully protected and work perfectly from 6V to 23VDC.

Connect the supplied 12V battery the DMXpix. With DMX data on the air, confirm again that the RC4Magic RF link is active by seeing the blue RFcon indicator blinking (not solid) on both the DMXio and the DMXpix.

Because the default string type is not the type you have connected, random LED blinks or levels may appear (or not).  This does not harm the pixel strings.

 

DMX Channel, String Type, and Color Order

DMX channels and string types are set with RC4 OneTouch, the same method used for assigning DMX channels and curves on RC4Magic dimmers.  A list of the DMX levels that correspond to pixel string types is provided at the end of this document.

First, we will configure Pixel Driver A:

A level of 30% selects the APA102 string type (RC4MagicPC Virtual TX levels are displayed in decimal levels from 0 – 255; 30% is decimal level 77).  Set DMX channel 9 to 30%, then tap the SetA button.  Driver A is now set to start on DMX channel 9 with an APA102 pixel string.

The first color of the first pixel in the APA102 string will come on at 30% brightness.  If the hardware pixel color order is not red/green/blue in the string, the first pixel may be something other than red.  For proper operation of RC4 ColorMatch, and to make console programming easier, the DMXpix can re-order the colors to be RGB:

When setting the channel and type (as outlined above), repeatedly tapping the Set button cycles through 6 possible color sequences.  Keep in mind that there are 2 sequences that start with each color, so two sequences in a row might start with the same color and not change with the press of the button.  A list of color sequences is provided at the end of this document.

With DMX channel 9 still at 30%, tap the SetA button again.  The color of the first pixel will change.  Do this repeatedly until the first pixel is red.  On your DMX controller, test the color order using channels 9, 10, and 11.  If the result is red, green, blue, the process is done.  If you find the order to be red, blue, green, then put channel 9 back at 30% and press SetA again, and repeat as necessary until you see the next option that begins with red.

Now we will repeat these steps for Pixel Driver B:

A level of 50% selects the LPD8806 string type (decimal level 128).  Set DMX channel 17 to 50%, then tap the SetB button.  (If you are using the RC4MagicPC Virtual TX tab, you should reassign the fader channels to be 9-16 on the top row, and 17-24 on the bottom row). Driver B is now set to start on DMX channel 17 with an LPD8806 pixel string.  The first color of the first pixel will come on at 50%.  If the pixel color order is not red/green/blue, the first pixel may be something other than red.  Repeatedly press the SetB button until the first pixel is red.  Test the color order with DMX channels 17, 18, and 19.  If necessary, restore channel 17 to 50% and press SetB additional times until the pixel color order is red/green/blue.

All settings are automatically saved in non-volatile memory and will be restored after subsequent power cycles.  Basic pixel string setup is now complete.  You have 1:1 DMX channel mapping of both strings, but starting on different DMX addresses.  This is much like other pixel drivers on the market.

 

RC4 ColorMatch White Balance Adjustment

The RC4 ColorMatch process is used to visually adjust white balance and make different pixel strings look more alike when operated side by side.  The easiest way to use ColorMatch is by eye.  Here we will match the APA and LPD strings, which deliver considerably different versions of white, neither of which look white at all (which is why we’re using these particular strings for this tutorial).

The ColorMatch process scales each primary color so that the desired white color temperature is produced when all 3 channels are at 100% on the DMX console.  To ensure maximum control resolution, at least one color should remain scaled at 100% — that is, it should not be scaled or attenuated at all.  Only one or two colors should be scaled back to achieve the desired result.

First, we will look at what the pixel string connected to Pixel Driver A delivers normally as white: raise DMX channels 9, 10, and 11 to 100%.  In many cases, a typical APA102 string looks somewhat pink or purple.

Adjust the levels of the DMX channels (9, 10, and 11) for a better white.  For example, pulling channel 9 (red) down to 43% (dec 109), and channel 11 (blue) down to 56% (dec 142) often results in an attractive white.  Remember, at least one channel should always be at 100% — in this case it is green.  Color varies from string to string, so use your eyes to find the white you personally like.

With the desired white visible on the pixel string LED, press and HOLD the SetA button for several seconds. When you see the color of the LED change slightly, release the button.  Be careful not to fumble and accidentally tap the button, which would reassign the channel and string type.  Now, set DMX channels 9, 10, and 11 to 100% and you will see the white color you selected.  The rest of the color palette is also normalized to this reference.

Next, we will match the Pixel Driver B string to provide a very similar white:

With channels 9, 10, and 11 still at 100% to see the reference white, raise channels 17, 18, and 19 to 100% and observe the normal white delivered by the LPD8806 string.  In many cases, this type of string looks very blue.  (You will also see one or more pixels illuminate on the Driver A string.  This is because DMX channels 17, 18, and 19 are also mapped on pixel string A.  Ignore this, covering those other LEDs if they are distracting.)

Adjust the levels of channels 17, 18, and 19 to improve Driver B white.  For example, pulling green down to 58% (dec 149) and blue down to 49% (dec 126) often looks quite good.  Use your eyes and find the white that matches the APA102 string on Driver A.

With an acceptable white color visible on the Driver B string, press and HOLD the SetB button for several seconds. When you see the color of the LED change slightly, release the button.  Be careful not to fumble and accidentally tap the button, which would reassign the channel and string type. 

RC4 ColorMatch for both strings is now complete.  All settings are automatically saved.

 

Setup Limitations and Best Practices

For optimal performance when using one WS2812-based pixel string and one of any other type, connect the WS2812 to Pixel Driver B.  Using Pixel Driver A for the WS2812 string may produce unacceptable flickering in one or both strings.

Using WS2812 strings on both drivers works fine.

Many 3-wire pixel strings are compatible with WS2812 and are subject to this same directive.  This includes the WS2811 (but not the 4-wire WS2801).  A list of WS2812-compatible pixel types is currently being compiled and may (or may not) include: INK1002, INK1003, TM1803, TM1804, TM1809, TM1812, TLS3001, TLS3002, CYT3001, and/or CYT3005.

RC4 Wireless is in the process of compiling a comprehensive list of compatible protocols, chip types, string brands, and models for each driver type.  For example, all Vivid RGB Lighting strings are WS2812 compatible.

 

Use RC4MagicPC and Discover RC4 Custom Pixel Profiles

Previous experience with RC4MagicPC is assumed.  For additional information and assistance, contact RC4 Wireless. 

For DMXpix with firmware version 4.050, RC4MagicPC software version 3.14.6.4 BETA or later MUST be used.  Earlier versions are not aware of pixel devices.  If you do not have the installer for this software, please ask RC4 Wireless to provide it along with an RC4 Encrypted System ID file paired with the supplied sample equipment.

Follow the setup steps earlier in the tutorial ( Using RC4Magic and the Virtual TX Tab).

The RC4Magic DMXpix is much more exciting when you use RC4 Custom Pixel Profiles.  Rather than simple 1:1 mapping of DMX channels to pixels, which is limited to just 170 pixels with a single DMX universe, RC4 Custom Pixel Profiles lets you group contiguous pixels to respond together, and assign a sequence of channels to be assigned repeatedly along the length of a string.  Then, using console programming of just a few DMX channels, visual effects can be mapped over two strings of 500 pixels – a total of up to 1000 pixels and the equivalent of 3000 control channels.

Initial Connection and Reading Settings in the DMXpix

With the link established (blue RFcon blinking on the dongle and the DMXpix), click the RC4MagicPC Settings tab, then click Read Device at the top right corner.  The green progress bar at the bottom of the window will indicate data transfer.  On completion, the name of the 5th tab in RC4MagicPC will become DMXpix.  Click that tab to display all the parameters for the device and their current settings.  Everything you set previously with the buttons – string type, DMX channel, and ColorMatch scaling – is displayed.

Sequence Length, Sequence Mode, and Group Length

With DMXpix firmware version 4.050, RC4 Custom Pixel Profiles consists of 3 parameters.  The first is Sequence Length.  This defines how many RGB console channels will be used in the profile.  Remember that each pixel uses 3 channels, so selecting a sequence length of 16 pixels will use 48 DMX channels.

What happens next is determined by the Sequence Mode parameter.  When set to Increment Channels, the 17th pixel acts like the 1st pixel, the 18th like the 2nd, and so on.  This series of pixels (determined by Sequence Length above) repeats from beginning to end – incrementally – all the way to the end of the pixel string, up to 500 pixels in length.

When set to Decrement Channels, the same series is mapped in reverse.  The 1st pixel on the console controls the 16th physical pixel, the 2nd controls the 15th, and so on, all the way to the 16th console pixel controlling the 1st physical pixel.  The pattern of 16 pixels repeats from end to beginning within each block – decrementally – all the way to the end of the pixel string.

Remember: in these examples we refer to 16 pixels because that is the setting of Sequence Length.  It can be anything you choose, from 1 to 500.

Increment/Decrement alternates between the two modes above, starting with the increment pattern.  Decrement/Increment alternates between the two modes, starting with the decrement pattern.  In these cases, the complete up/down (or down/up) pattern repeats every 32 pixels (16 + 16).

Using multiple strings with different Sequence Modes in one display provides visual variation with strong symmetry.  Using different Sequence Lengths and Group Lengths departs from this symmetry, introducing rolling “seams” with wider and narrower pattern renderings.  The power of this effect should not be overlooked.

With pixels grouped and mapped to DMX channels within the DMXpix, the rest of the creative work is done at the DMX console, limited only by programming abilities and imagination.

Marquee scrolling – a very common application for pixel strings – is easily done using as few as 3 pixels (9 DMX channels).  Smooth fades, color gradations, negative or positive scrolling space, and so on, are easily created at the console.  Color, speed, depth, pattern, brightness, effect width – it all becomes part of console scenes and cues, truly personal creations of the lighting designer.

Quick Select Options

RC4MagicPC provides five Quick Select options that populate the 3 parameters described above.  DMX 1:1 is the factory default configuration, mimicking most pixel drivers on the market: 510 DMX channels control 170 RGB pixels (and the last two channels in the universe control red and green for the 171st pixel).

DMX 1:3 demonstrates grouping 3 pixels to each control channel, so that 501 DMX channels will control 167 trios of pixels out to the 500-pixel maximum of one DMXpix driver.

Seq 5 incrementally maps 15 console channels (5 x RGB) to individual (not grouped) physical pixels.  Seq 16 incrementally maps 48 console channels (16 x RGB) to physical pixels. When experimenting with these, try different values for Seq Mode and Group Length.

Unison emulates regular LED tape: all 500 pixels are mapped to the same 3 RGB control channels.  This is a functional waste of a pixel string, but is useful for fine-tuning ColorMatch white balance while viewing the composite white of the entire string.

Configuring one pixel string to behave like multiple equal lengths of regular LED tape is easy.  For example, configure a 60-pixel string with a Sequence Length of 2, and a Group Length of 3o.  Now you have separate RGB control of the first and second halves of the string.  Divide it up into as many equal parts as you like.

Fine Tuning RC4 ColorMatch Settings

RC4MagicPC provides direct numeric editing of ColorMatch values.  After finding approximate settings by eye, fine-tuning provides the precision needed for truly optimal visual appearance.

Save Identical Settings to Multiple DMXpix Devices

To send the same settings to multiple DMXpix devices, keep RC4MagicPC open with the DMXpix tab visible.  Disconnect the first DMXpix, plug in the next, wait for the wireless link to connect, then click Send Pix Settings.  There is no need for the software to Read each different device first, which would overwrite the settings on screen.  Only the first DMXpix must be read (by clicking Read Device) to initially enable the DMXpix tab.

 

Future Features

With DMXpix firmware version 4.050, dividing a string into individually controlled segments is done with the Group Length parameter, forcing all segments to be of equal length.  A future firmware update will allow multiple groups to have unique lengths.

In the somewhat more distant future, the next generation of RC4 DMXpix will allow DMX channels to control Custom Pixel Profile parameters in real-time.  The Sequence Length, Group Length, and other parameters will be dynamically controllable rather than fixed in configuration settings.

The future of RC4 pixel control is bright!

RC4Magic Series 3 Firmware Version 4.050 (2015)
DMXpix Button Functions

Power-Up “Hidden” Functions:

Func:                                      Invoke CodeLoader for Updates

SetA:                                      Select Private System ID0

SetB:                                      Select Private System ID1

SetA+SetB:                           Select ID3 (Public)

After Power-Up (Normal Running Mode), Tap Button:

SetA:                                      Set OutA DMX Channel, Select Pixel String Type1
Repeated pressing cycles through 6 pixel color orders2

SetB:                                      Set OutB DMX Channel, Select Pixel String Type1
Repeated pressing cycles through 6 pixel color sequences2

Func:                                      (not used)

Press Func (works like keyboard shift key) and Tap Button:

Func+SetA:                          Restore Factory Default Settings (Incl. Select ID0)

Func+SetB:                           (not used)

Long-Press (Press and hold several seconds):

SetA:                                      Use current DMX levels for OutA pixel 1 as
ColorMatch white reference for OutA.

SetB:                                      Use current DMX levels for OutB pixel 1 as
ColorMatch white reference for OutB.

Func:                                      Invoke RC4 Dongle Mode for RC4MagicPC.
(CodeLoader USB Cable Required)

 

1 DMX Level Selection of Pixel String Types:

30%                        APA102

50%                        LPD8806

70%                        WS2801

100%                      WS2811/WS2812

1 Various other string types are compatible with these.

Driver firmware for additional string types will be introduced from time to time and are easily loaded with the RC4 USB CodeLoader cable.

Color Sequences:

RGB (red/green/blue)

GRB

RBG

BRG

GBR

BGR (blue/green/red)

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