Questions tagged [dmx512]

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

Filter by
Sorted by
Tagged with
1
vote
2answers
79 views

How DMX512 protocol da daisychain?

First of all DMX signal use differential-pair signal, RS-485. Many website said that each device have programble unique ID then we can send data to each ID by following protocol. (seem like they same ...
0
votes
2answers
59 views

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 ...
0
votes
0answers
289 views

How to interface a RPi Pico to DMX / RDM

Years ago, I was looking at creating a stage DMX controller using AVR. Time moved on and the Raspberry Pi Pico has now been released. I'd like to revisit the project using a Raspberry Pi Pico, which ...
0
votes
0answers
30 views

DMX over RJ45 daisychain extra pins?

Im building a DMX controller that uses RJ45. (Controller as in lights are connected to it) I will obviously have 2 RJ45 jacks for daisy-chaining. What I was wondering is, I've seen that multiple ...
0
votes
1answer
30 views

MAX485 DMX connection polarity/pinout

Im working on an Arduino project that involves receiving DMX with a MAX485 chip. The pinout of the chip has the 2 dmx pins labeled as A and B, but all the DMX pinouts have them labeled as + and -. ...
0
votes
1answer
2k views

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) > ...
8
votes
2answers
700 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-...
0
votes
2answers
167 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-...
0
votes
1answer
573 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 ...
1
vote
1answer
132 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 ...
-1
votes
2answers
83 views

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 ...
0
votes
2answers
1k 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 ...
1
vote
2answers
247 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, ...
2
votes
2answers
557 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 ...
6
votes
1answer
2k 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 ...
0
votes
1answer
443 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 ...
2
votes
1answer
822 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 ...
3
votes
1answer
6k 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. ...
0
votes
1answer
54 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 ...
0
votes
1answer
43 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 ...
1
vote
2answers
2k 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 ...
1
vote
0answers
273 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 ...
1
vote
1answer
176 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, ...
0
votes
1answer
49 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 ...
0
votes
2answers
618 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 ...
2
votes
3answers
352 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 ...
0
votes
1answer
55 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....
2
votes
1answer
891 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 ...
0
votes
2answers
779 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. ...
1
vote
1answer
6k 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. ...
2
votes
1answer
341 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 ...
5
votes
2answers
10k 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?
1
vote
2answers
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 ...
5
votes
1answer
673 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. ...
1
vote
1answer
842 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 ...
3
votes
1answer
16k 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 ...
1
vote
1answer
895 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 ...
2
votes
2answers
2k 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 ...
-2
votes
1answer
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 ...
3
votes
2answers
10k 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 ...