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Supported DMX Adapters


bob

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  • 1 year later...
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All of the LOR USB 485 devices support DMX output with the proper adapter cable.

 

I have one of each of them and they handled the DMX output quite well in a recent test with some DJ type lights.

 

Since the DMX timing is generated by your computer, it may have erratic output if your computer gets overloaded.

 

The most reliable interfaces have outboard timing that does not rely on your computer.

 

These would be the Enttec Pro (not the Open model), DMXKing, Fusion Pro and the Actidongle.

There are others, but these are the most popular.

 

Street prices range from $50 to $150 each.

 

 

See also: http://forums.lightorama.com/index.php?/topic/20771-using-lor-dongle-with-dmx/

 

and: http://forums.lightorama.com/index.php?/topic/24129-usb-to-dmx-adapter-suggestions/

 

and: http://forums.lightorama.com/index.php?/topic/27403-lor-usb-485-dongles/

Edited by Ken Benedict
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  • 2 months later...

For this year's show I have acquired 3 strips of 150 RGB LED pixels, and I got 3 of the HolidayCoro TinyPix pixel controllers for them.  I have connected one of the TinyPix controllers to a LOR 485b adapter with a custom wired crossover cable.  So far, I have only hooked up one, and for the most part, it works, and I've created some complex sequences in the S3.10 sequence editor to test them.  It's all pretty cool and I'm really stoked about all the possible things I can do in my show this year.  Each strip has 150 LEDs X RGB = 450 DMX channels, almost a whole universe per strip.

 

But when I say it works for the most part, I have noticed some minor glitches in the fast parts that appear to be lag in the data stream.  It appears that something is having trouble keeping up with the high 250K data rate of the "Raw" DMX protocol.  I worried about what's gonna happen when I try to run 3 universes instead of just 1.  And try to run it on an older computer.  And run all the adapters thru a hub since I don't have that many available USB ports.

 

Can someone shed some light on the practical limitations of this set-up?  Is anyone successfully running 1350 DMX channels / 3 Universes using LOR-485b adapters on an old laptop thru a USB hub?

 

I am considering getting a RPM E1.31 to DMX bridge.  I was wondering if that might take care of the lag problem.  E1.31 is of course, ethernet which should have plenty of bandwidth. I'm sort of assuming that the bridge must buffer and retransmit the data and would thus correct any timing issues.  I read thru the E1.31 wiki and didn't see anything about the packet timing being critical.  The bridge is about $75 but I'm already way over budget this year and I loathe to spend even another $75 right now.  Anyone have any practical experience with bridges fixing timing problems?

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You may be going too fast for the DMX data stream; it only refreshes 30-40 times per second and sends out 450 channels when it does.

 

Try slowing down your timing sequences.

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Yes, you have to watch your timings used with DMX.

 

The maximum refresh rate for DMX is 43 frames per second which is about 23 milliseconds timing marks.

 

40 FPS is 25 millisecond timing and 20 FPS is maximum 50 millisecond timing marks.

 

Anything generated faster or between your FPS timing are not sent to the lights.

 

I recommend only using fixed timing with DMX to prevent missed events. I learned this last year, my display for the past 3 years was having troubles and did not respond correctly to my seauences, until the light over my head finally got bright enough to correct the timing in my sequences.

Edited by Dennis Cherry
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I'm not going THAT fast!  My test sequences are at 20FPS.  And my desktop test machine is a powerful one: i7-920, 4GHz, 12GB Ram, Win8.1, and I try to keep my background processes and services at a minimum.  The machine I was hoping to run the completed show on however, is a laptop with a 2.2GHz Core 2 Duo and 4GB ram.  It only has 3 USB ports and I need one for the mouse, so I'm gonna have to use a little 4 port USB 2.0 hub for the LOR and DMX adapters.  I'm gonna try and get everything plugged into the laptop tonight for a full scale test and see how it does.

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The DMX dongle you are using (the LOR 485B) does not have any on-board DMX processing; it relies on the CPU for this.

 

Using 3 of these on an older computer with a USB hub will bring your DMX network to it's knees.

 

See this solution: http://forums.lightorama.com/index.php?/topic/16319-supported-dmx-adapters/?p=260569

 

The LOR network only sends out CHANGES, which is much lower traffic to handle.

Edited by Ken Benedict
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