Understanding DMX Events

A DMX event contains specific attributes which are used to control DMX devices. DMX events are added to scripting software such as COBRA Show Creator and Finale3D. You can also create the raw script CSV script format using Excel or a common text editor. COBRA provides example scripts on 6.0 to help.

Before we begin, let's remind you that DMX is outputted from the 36M or 72M only with the use of the 36M/72M DMX Upgrade Kit.

Let's start by introducing DMX event attributes and their purpose.

• DMX Universe - The DMX universe (1-99) is a way to limit which events are uploaded and outputted by specific COBRA 36M or 72M modules.  Only events with the same DMX universe as the 36M/72M is uploaded to that module and outputted when the script is running.  On the 36M/72M, there is an assigned DMX universe. You can access this by pressing the CHANGE BANK button until the DMX Universe displays. Then, by pressing CH+ or CH- you can change the DMX universe assigned to the module. This is remembered on the module even if powered off or the batteries are removed. Please note that the DMX Universe cannot be changed while the 36M/72M is armed.
  Any event whose DMX universe matches the 36M/72M DMX universe is uploaded to that module and outputted when running the script. In short, the event DMX universe allows you to choose which modules output that event. You can also set multiple 36M/72M modules to the same DMX universe.
  The purpose of limiting DMX events to specific modules is to: 1) reduce the upload time to modules by limiting the total # of events per module, and 2) maximize the number of supported DMX channels (200) per module, and 3) allowing you to keep DMX devices on a specific starting DMX channel such as 1. For example, many DMX devices occupy several channels. By keeping all devices on the same starting channel, you can set each 36M/72M module to a different universe and interchange devices between modules without having to set different starting channels. Yes, this sounds a bit complex, but once you start designing DMX shows, this will make more sense.                                                                                                                                       
• DMX Channel - The DMX channel is the unique channel you wish to control and set an associated value to. DMX channels range from 1 to 512. DMX hardware devices will occupy a minimum of one DMX channel and often occupy multiple channels. Think of the channel as a knob you can rotate to turn on and set to a specific level which is the DMX value, explained below.
  
  
• DMX Value - The DMX value is a number 0-255 which sets the level of the associated event DMX channel. Every DMX hardware device has a documented channel and value range to perform specific functionality. For example on a simple DMX RGB light, setting channel 1 to any value between 1 and 255 will act as a master "on" switch to the device. Then, setting channel 2 to a value between 1 and 255 will turn on and control the intensity of the red LED.
  
  
• DMX Pulse - The DMX pulse is the total length of time the associated DMX channel and DMX value is outputted from the module. The accepted format is MM:SS.XX. For example, 1 minute, 10.3 seconds is 01:10.30. By leaving this field blank, the DMX channel and value will be sent continuously until another event with the same DMX channel and value is sent. Leaving this blank is helpful when setting a master "on" switch for a specific DMX hardware device at the beginning of the script and then turning it off at the end of the script. At any time the DMX channel and value is not sent, a value of 0 is sent in the module's DMX signal output. For example, if you set a DMX channel and value mid-script for a defined pulse, once that pulse is over the value of 0 is sent to ensure it's off and not functioning for safety reasons.

The following details the specific DMX event columns within the COBRA Script File Format.

To help illustrate an example, let's create a DMX script to turn on a red LED for one second, a green LED for one second, a blue LED for one second, and then all three LEDs for one second and then turn them off. This is all performed on a single DMX RGB LED hardware device.

Note that in this example, all events are on the same DMX universe. This means that we have all three RGB LED devices daisy-chained together and connected to a single 36M/72M module. The RGB light used in the below example is detailed in Understanding DMX Hardware Devices.