Questions tagged [dmx512]

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

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STM32 skips UART frames after framing error

I am currently developing a DMX512 receiver with an STM32F767ZI. DMX512 is basically a protocol transmitting a byte array via RS485. In summary it works like this: > 92us low signal (called break) > ...
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630 views

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-...
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65 views

Is it acceptable to have A & B wire at same voltage in RS485

I'm trying to implement DMX with a Raspberry Pi after reading this page: https://www.element14.com/community/groups/open-source-hardware/blog/2017/08/24/dmx-explained-dmx512-and-rs-485-protocol-detail-...
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DMX protection circuit (diode clipper)

TL;DR I’m building a board that bridges the common types of DMX connector (various forms of XLR, RJ45, tails and product-specific terminals). There is a possibility that someone could accidentally ...
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197 views

RGBW Cree XM-L LED power circuit HELP!

I have 10 Cree XM-L RGBW LEDS and I would like to power them from a 12V power supply. I came up with this idea: A 12V 30 amp power supply powers 3 different step down buck converters (10 amps each ...
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95 views

LED Controller + LED Panel with common cathode

I have a 3-CH DMX controller (5-24V, 5A/ch, common anode) from amazon (don't know if links are desired here) and a 12V 100W MCPCB LED panel, which unfortunately has a common cathode. The panel is ...
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What communication method shouild I use [closed]

So I wan to control a bunch of devices. I though first of using RS485 but after some digging I figured out this might not work as I don't really have a pure daisy chain. The configuration I would like ...
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424 views

Questions about DMX512 protocol/STM

I want to make a DMX512 transmitter with a STM32F103 using HAL, CubeMX. I found some documentation like here about the protocol: Lighting-Control-using-DMX512-protocol-on-STM32. Sadly it does not ...
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2answers
162 views

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, ...
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2answers
289 views

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 ...
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1answer
903 views

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 ...
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139 views

Can you determine needed input voltage from just looking at this circuitboard?

Question poster's level of knowledge: BEGINNER/NOVICE/MENTALLY CHALLENGED Device: A stage lighting pan/tilt motor, for one axis. Used in sets of two to provide remotely controlled X and Y movement ...
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293 views

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 ...
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1answer
5k views

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. ...
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1answer
48 views

Is this cable suitable for DMX wiring?

I'm running some permanent wires for DMX control in the small theatre in our facility, and we have a box of this cable left over from a different job. I've read a lot about how you shouldn't mix ...
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37 views

Sharing DMX512 GND with Power GND

I would like to connect multiple devices using DMX512 protocol. I would like to use the same cable for both power (12V, each device draws around 10W) and communication. For power I need 2 wires and ...
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1k views

DMX: What should I do with ground and shield?

I'm currently developing a DMX interface (master interface) with USB and Ethernet connections. The power for my device I'm retrieving from the 5V of the USB connector. The shield of the USB connector ...
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180 views

Audio reactive lights - DMX vs I2C

I need to build a system to control lights using line-level audio signal. My idea is to acquire the signal from my mixer using a microcontroller (or FPGA), apply some filters and finally drive 5 leds ...
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1answer
155 views

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, ...
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45 views

Using cat5 and mic cables within same DMX512 universe

I understand that I'm not suposed to use mic cable for DMX sygnal. And that's the reason why the standard mandates 5-pin XLR connectors. I also know that in practice 20 out of 20 events I've witnessed ...
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168 views

Use AC to illuminate DC LED's

I need guidance in the explanation of utilizing LED light bars for a different function then designed. I do stage production, sound and lights for concerts and would like to adapt these LED light bars ...
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3answers
324 views

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 ...
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1answer
49 views

Can I use SLIP on the same line as DMX?

I have a CAT 5 line with 12 DMX devices, each taking 4 channels. I also have a CAT 5 line with 8 microcontrollers (ex. Arduinos). These controllers need to send back data, and require error detection....
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1answer
811 views

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 ...
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345 views

Multiple led drivers for a single LED

I have a couple of moving heads like this They have a QCL (Quad color led chip) Theres a total of 10w. Most of the time I don't use the colors, I just use the white quadrant, which I presume is 10w. ...
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1answer
5k views

Can I connect a single color LED string to a RGB DMX512 controller? [closed]

I am planning on doing a bit of a light show this christmas on my house, I have ordered a bunch of 5050 RGB LED Strings, DMX controller, DMX Bridge and will be running the show using Vixen software. ...
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1answer
284 views

choosing the right Opto isolator?

In the process of developing an RDM Compatible DMX receiver board (using a ATMEGA328) and I have been fortunate enough to come across kimliv's most informative answer concerning such a board; DMX on ...
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8k views

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?
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1k views

PIC24F UART Rx Interrupt not firing

I am currently trying to write code for a 48 channel DMX controlled dimmer using a PIC24FJ32GA002. Using a scope I have confirmed that there is a DMX signal reaching the Rx pin of the UART which has ...
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1answer
612 views

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. ...
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1answer
556 views

Control DMX512 from audio out

I'd like to find a simple way to control the lights in our local theater. We have panels and everything, but I'd to experiment with the way I can control the colors of the lights. I'm a web developer ...
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1answer
14k views

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 ...
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1answer
832 views

512 channel LED strip controller over RJ45 (TCP or UDP based commands)

How would you make the following? I'm looking for a 512 channel LED strip (varying size) dimmer, controlled over TCP/IP or UDP. My dream board has: 512 individual channels @ 12V Each channel ...
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2answers
1k views

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 ...
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68 views

Methods for controlling power outlets?

I'm looking for ways to control power outlets (to turn them on/off) remotely and to schedule them. This is not for my home, but for a larger exhibition hall. So far I have found two different ...
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2answers
9k views

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 ...