Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [dmx512]

DMX is a simple protocol based on RS485 used by the entertainment industry for controlling lighting.

42 questions
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Effect of "wrong" driver with slightly long RS-485 stubs

I have a planned 250 kbit/sec, single-pair, 36-metre RS-485 installation where it is advantageous for wiring purposes if the stub lengths can be a little longer than optimal. There is a single almost-always transmitter and three almost-always…
jonathanjo
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What is the relationship between DMX and RS485? Are there any breaks in the protocol in relation to one another?

As far as the DMX is RS485 and at what points one moves away from the other? breaking the standard/protocol?
Delfino
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Blowing out MAX485 transceiver

[Edit: revised my complete post] I have a problem with a project I'm currently working on, and I would really appreciate some help. I created 10pcs of 100W RGB LED modules that are communicating via DMX512. Already two times now, my MAX485…
MartinF
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DMX512 packet issue (no break?)

I'm not sure if I'm reading this wrong or something, but this is a trace of the DMX packet that's coming from my USB-RS485 module then being converter to UART logic levels for my microcontroller. There are a few things I don't think are…
Sensors
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ESD protection on an isolated circuit

I'm currently working on an RS485 DMX circuit and am thinking about proper protective measures. I've oriented myself on this question. I understand that galvanic isolation does not equal ESD protection, so I need some TVS diodes on the incoming…
CShark
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How to de-couple DMX512 with opto-isolators?

I'd like to build a DMX512 device. The problem I have is how to decouple the device from the bus. I decided to use opto-isolators, but how should I wire the diode part of the isolator? Since I need TTL/RS232 levels on the controller side, I'm using…
polemon
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Questions about prototyping a DMX Splitter

Original schematics I want to make the following DMX Splitter: Credits by J. Mack, see Full article: DMX Splitter Changes Changes made by me (with help of Maple, Transistor and many others, thanks for that): Four instead of three output…
Michel Keijzers
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UART Synchronization After Break

With the assumption that not all UART are create equal and that documentation in general is not sufficient to answer this question, I have to ask how can I tell which UARTs (or generally asynchronous serial receivers) properly handle the Break…
bscloutier
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How can I reuse a crowdled bracelet?

I have been to an event last night, where I some wristbands produced by the Crowdled company (see links at the end). Material of one band: 3 colored leds (2 in total) and a button. Runs on battery. For the pictures I opened the bands (2 screws). In…
Daniel Herold
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DMX on Arduino with RS485

I'm implementing DMX on Arduino. DMX uses the RS485 standard to communicate. In the specifications of RS485 it notes that there is a positive line, a negative line and a ground line. If the positive line is at higher potential than the negative…
jdepypere
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DMX (serial first) over Xbee Pro Module with Arduino

I want to transmit a DMX signal over a Xbee RF module. I came to realize that sending 1 Universe of DMX can be problematic. Looking at the Open DMX page we see that the computer's DMX information is sent via USB, then converted to Serial output(via…
Roelf Daling
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How to test a DMX splitter

This question is related to the DMX splitter I'm building and shown in Prototyping a DMX splitter. However, for testing a different question is appropriate. I never really tested a hardware device, so be gentle please. The intended use for the DMX…
Michel Keijzers
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Do I have to use a MAX485 chip in front of an ATXMega microcontroller?

I'm doing a project which involves receiving DMX 512 information on an ATXmegaA3u microcontroller. I've successfully implemented the protocol using the onboard USART of the microcontroller. Basically, 2 frame errors, then 512 valid bytes. Regarding…
Kévin Isabelle
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Can I use ethernet instead of DMX for DIY led lighting?

I've read that while most pro-lighting is uses dmx, some intelligent lighting rigs use ethernet. I'm interested in building some MCU controlled L.E.D. footlights for my stage show, and currently know nothing about dmx and damn little about lighting…
Iain Duncan
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Designing a PWM controlled power supply for a 30W RGB LED

I am building a DMX controlled light using an Arduino, but I am not sure which power supply I should use to power the LEDs which run at 36v (10 in series, 3 rows) 30W. The main problem is whether or not there is a way to control an LED colour using…
Nikita K
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