ArtNetOutModule¶

Category: driver | Tags: ☸️🟦🐙

Sends DriverLayer pixels as Art-Net DMX over UDP. Each frame is split across consecutive Art-Net universes of 170 RGB pixels (510 channels) each. The number of universes sent per frame is ceil(total_pixels / 170) and scales automatically with the panel size.

Controls¶

Control	Type	Range	Default	Description
`universe_start`	slider	0-255	0	First Art-Net universe number
`ip`	text		255.255.255.255	Destination IP (broadcast or unicast)
`enabled`	toggle	0/1	1	Enable/disable sending

Wiring¶

{
  "type": "ArtNetOutModule",
  "inputs": { "layer": "<driver-layer-id>" }
}

Art-Net packet format¶

Each universe is sent as a standard Art-Net OpDmx packet (Art-Net 4 spec):

Offset	Size	Content
0	8	`"Art-Net\0"`
8	2	OpCode `0x00 0x50` (OpDmx, little-endian)
10	2	ProtVer `0x00 0x0e` (14, big-endian)
12	1	Sequence (0 = disabled)
13	1	Physical (0)
14	2	Universe number (little-endian)
16	2	Channel count (big-endian, always even)
18+	N	DMX data: R, G, B per pixel

Multi-universe example¶

A 20x20 panel = 400 pixels = ceil(400/170) = 3 universes:

Universe	Pixels	Channels
0	0-169	510
1	170-339	510
2	340-399	180 (padded to 180, already even)

Health report¶

universe_start=0 packets_tx=1234 ip=255.255.255.255

Test coverage¶

Unit tests in tests/test_artnet.cpp:

Test	Level	What is verified
Lifecycle without layer	`smoke`	No crash when `layer_` is null; `packets_tx=0` in healthReport
Sends packets when wired	`behavioral`	`packetsTx() > 0` after one frame with a real DriverLayer
Multi-universe: 170px = 1 uni, 171px = 2	`behavioral`	Universe split at exactly 170 pixels
Packet header bytes correct	`behavioral`	Art-Net OpDmx header present after one send
ArtNetOut loopback to ArtNetIn	`integration`	Full send/receive on 127.0.0.1; `packets_tx > 0` confirmed

Live tests (deploy/live_suite.py, deploy/livetest.py):

Test	Level	What is verified
test5 Art-Net loopback (PC)	`integration`	`packets_tx > 0` and `packets_rx > 0` on PC broadcast loopback
Two-device Art-Net (PC sender)	`integration`	`packets_rx > 0` on MM-70BC ESP32 over LAN broadcast UDP

Tags¶

Emoji	Meaning
☸️	Driver
🟦	2D+
🐙	WLED-compatible protocol