USB DMX Controllers

Similar to the ethernet to DMX controller, I built a pair of devices to control DMX fixtures over a simpler USB connection. Often a direct USB connection is much easier to set up and use in a test environment or a small-scale production when a full network setup with multiple ethernet runs is not necessary. The two USB controllers that I built have similar offerings as multiple options on the market, but I can build them at a much cheaper price and am able to extend the firmware functionality further than what is available currently.

USB DMX Controller Standard

This is a ‘dumb’ implementation of the USB to DMX serial conversion. There is no microcontroller or state maintained within the device - it simply converts the incoming USB signals to RS485, it is up to the data source to properly format the data as DMX. While there is ESD and transient voltage protection through the circuit, there is no active isolation between circuit and the DMX output data and ground. This device is designed for quick test and verification use in systems, not to run live show or production from. The pros are that it is cheap and the parts count is very low.

USB DMX Controller Pro

The Pro version of this controller is much more useful as a general tool and to run actual content. While the input USB and output XLR5 interfaces are the same, this design supports multiple operating modes and remote configuration. The device can be used in standard DMX output mode where incoming DMX data is buffered internally and output exactly at the framerate configured by the user, even if connection to the data source is lost. Other modes include:

• sync mode to output data exactly at the cadence it’s received
• test mode which will output a continuous test pattern (multiple patterns available, configured by the user)
• static mode which will output a continuous static custom DMX universe that the user can configure.