What is RDM?
RDM (Remote Device Management) is a communication protocol specified by ANSI E1.20 which deals with the remote identification and configuration of equipment for theatrical and lighting purposes. It is an extension to the ANSI E1.11 DMX512 protocol, is is designed to be fully compatible with both RDM enabled and legacy non-RDM devices. With RDM, DMX devices can be remotely addressed, identified, and configured using an RDM controller.
While DMX is a straightforward protocol (each byte represents one of 512 addresses), the RDM protocol is more complex because of its bidirectional nature. The controller and devices share the same DMX universe, so the communication protocol must specify which devices commands should be addressed to, and where any replies should be sent. Commands may include data payloads. For example, setting the personality requires one byte of payload data indicating the personality number to set. Other commands, such as setting the device label, may carry up to 32 bytes of ASCII characters.
The E1.20 specification lays out commands which allow rich control, configuration and monitoring of DMX devices. All devices on a network can be enumerated through a 'discovery' process. The DMX address of fixture, and their personalities can be configured. Diagnostic information such as sensor values, error counts, and more can be viewed. In addition to the commands outlined in the standard, the RDM protocol is flexible and allows extension by manufacturers to add their own proprietary commands.
Planned Updates
This tool is in development. Planned upgrades include:
- Decoding of multiple sequential frames with transaction highlighting
- Richer payload breakdown for standard RDM PIDs
- DMX frame decoding
- Discovery response decoding
- Upload of user-defined PIDs and payload breakdowns
- Integration with calc.50x.ca for byte-level decoding