You Need to Know About DMX512 Control

What is DMX512?

DMX512 is a system for controlling lights but it can also control other things. 

“Digital Multiplex” tells you how it works from the name itself. Like a time slot, the packets that make up most of a protocol tell which devices should get data.

 In other words, there is no address and no information about it. 

In this case, the address is determined by where the packet is.

In reality, the process is straightforward. 

You can make electrical connections with 5-pin XLR connectors, and the interface in a balanced line pair (with 0 V reference). 

You can send the bytes and bits to a serial port of 250,000 bps. 

The RS-485 standard is a type of electrical interface.

It’s important to note that “512” in “DMX512” is also very memorable. 

This number shows that a packet can contain up to 512 bytes of data (513 are sent, but the first is not used). 

One package can hold all of the information in a DMX universe.

If each light fixture only supports basic dimming for a single color, like white light, then a single data byte can control a light fixture and offer up to 255 levels of brightness, from off (zero) to fully on (255), this means that you can control 512 devices.

A typical RGB control scheme for red, green, and blue light fixtures needs three data bytes. 

In other words, you can only control 170 RGB devices because a packet (and, by extension, the DMX universe) can hold only 512 usable data bytes.

History of DMX

Before DMX 512, stage lighting manufacturers used a wide range of proprietary and incompatible wire types, which caused a lot of confusion and extra wiring. 

Then the DMX 512 standard was created.

The United States Institute of Theater Technology (USITT) made DMX 512 in 1986, and USITT DMX 512/1990 came out in 1990.

Modern DMX512, on the other hand, was made by the Entertainment Services and Technology Association (ESTA).

 In 1998, ESTA started to send DMX512 to the American National Standards Institute (ANSI). 

ESTA made changes to the last version of DMX512 in 2008.

Basics of DMX control

You can look up “Digital Multiplex Signal” using the letters “DMX.” 

Because it can work with 512 channels, it is often called DMX 512. An RGB light has three different “channels” or colors.

 If you think about an RGB light, you may be able to understand better what a “channel” is. 

One DMX world can control up to 512 monochrome or 170 RGB lights. Using a DMX Decoder/Driver, each fixture receives a unique 512-universe DMX address, and then set up your lighting scenarios to work with those addresses.

What is a DMX address?

A channel is another name for a DMX address. If you want to run several fixtures separately, you’ll need to give each one a unique starting address that isn’t part of any other fixture’s channel group.

• The address, also called the starting address, tells you which channel the light is now tuned to.

• A fixture’s settings are controlled by a DMX personality, which is a channel or group of channels.

Some DMX fixtures have a dip switch that lets you change the default factory address.