Lighting
DMX512
01 — Definition
The protocol that drives stage lighting — Digital Multiplex, serial data at 250 kbaud over RS-485. One universe is 512 channels (slots), each running 0 to 255, refreshed up to 44 full frames per second. Count on 300 m maximum on quality cable, a 5-pin XLR as the standard connector, and a 120 Ω terminating resistor at the end of every line.
02 — In the field
Forget the 120 Ω terminator at the end of a long run and the data reflects: fixtures flicker or jump erratically, especially at the end of the chain. Always keep a DMX terminator plug on you.
04 — Sources
- ANSI E1.11-2008 (R2018) §3.34 — 512 slots de données par univers, le slot 0 étant le START Code
- ANSI E1.11 §8.1 — valeurs 0 à 255 sous START Code nul ; §7.1.1 — XLR 5 broches ; §4.9 — terminaison 120 Ω
- ANSI E1.11 tableau 6 — 250 kbit/s (245–255), 44 trames/s au maximum