Universe, channels, address
A DMX universe has 512 channels, each set from 0 to 255. Each fixture uses a run of channels from its start address: an RGBW PAR in 4-channel mode set to 001 uses 001 to 004; the next one is set to 005.
The mode decides the channel count
The same fixture often offers several modes: a short one (intensity and colour), a long one (macros, strobe, 16-bit fine control). The mode set on the fixture and the one chosen in the software must be the same, otherwise channels are offset. Every page in the catalogue gives the modes and their DMX chart.
Patch example
| Fixture | Mode | Channels | Address |
|---|---|---|---|
| 4 RGBW PARs | 4 channels | 4 each | 001, 005, 009, 013 |
| 2 wash moving heads | 14 channels | 14 each | 017, 031 |
| 1 hazer | 2 channels | 2 | 045 |
Some channels stay free: keep room to add fixtures without readdressing everything.
Cabling, without surprises
- daisy-chain fixtures (DMX out to the next one's in), no "Y" splits;
- a terminator (120 Ω) at the end of the line avoids flicker on long runs;
- beyond 32 devices or a long distance, use a splitter.
In Halyx
In Patch › Add, choose the model, mode and universe: Halyx offers the next free address, and can address fixtures over RDM when they support it, from Outputs.
