When a customer says that a lighting console should control an LED screen through DMX or Art-Net, the real requirement is often a small set of basic functions: switch input, adjust brightness, adjust volume, call a scene or start/stop predefined content. Development should begin by defining the control object, direction, network boundary and exact model. Otherwise “the lighting console can control DMX lights” is incorrectly treated as “the console can control every function of the LED processor.”
DMX is a control-channel system. Art-Net is commonly used to transport DMX data through an IP network. Neither is automatically the LED pixel-data protocol. The video processor, sending device and receiving cards still have to transmit the image data to the cabinets. A reliable design should draw the lighting console or gateway, protocol conversion, processor control interface and video path as separate blocks.
Clarify whether “local” means no internet or no network. A direct Ethernet or Wi-Fi connection is still a local network and still needs an address plan, ports, isolation and permissions. Confirm whether the exact processor model and firmware provide a local API, TCP/UDP, HTTP, serial, GPIO, preset-scene or other control interface. Model and firmware must be written in the requirement. The API of one processor must not be assumed to work with a different model such as TB40 or VX400 Pro.
Use a control matrix: input switching, brightness, volume, scene recall, play/pause, status reading, error reading and standby/power functions. Mark each item as natively supported, requires external software, requires manufacturer documentation or not yet verified. For brightness and volume, specify whether the target is the processor, playback computer or display, because different layers may produce different results.
Development should start on an isolated network and a test device. Use the manufacturer’s official manual or SDK to verify login, address, port and command format. Test one control object, record the response and define a recovery method. Do not send unknown commands to a customer’s live screen, place shared passwords in a script or publish cloud credentials. If the required function is not supported, state a tested alternative such as processor presets, playback-software hotkeys, serial control, relay control or a manufacturer gateway. Each alternative still needs a real test.
The handover should contain a control-boundary table, network topology, point mapping, model/firmware versions and rollback method. The key sentence is not “the system supports API control,” but “these specific functions are confirmed on this exact model and firmware; these other functions still require manufacturer confirmation.” This protects the customer and keeps development measurable.
The developer should also receive a test matrix rather than a verbal request. For each command, record the trigger, target device, expected response, time-out, retry rule, visible effect, safe fallback and log entry. Test commands with the display in a safe scene and verify that a failed request does not leave the screen in an unknown state. If an API can change brightness, identify the minimum and maximum values, the unit, the persistence rule and the operator override. If it can switch inputs, define what happens when the selected source is missing.
Security is part of a local control design. Use a dedicated network or VLAN where appropriate, restrict administration to authorised workstations, avoid hard-coded shared passwords and disable unused remote functions. Store credentials outside public scripts and documentation. If the manufacturer requires a proprietary SDK or permission, record that dependency instead of presenting the gateway as a self-contained product.
A good prototype has a manual fallback. The operator should still be able to select a tested processor scene or playback source if the DMX gateway, Wi-Fi or lighting console fails. This is especially important for events where a basic brightness or input command must not become a single point of failure for the complete LED display.
Keep the fallback local. If the requirement is specifically “no internet,” the basic control and recovery path should continue to work when the WAN connection is removed. Test the gateway, processor and playback computer on the approved LAN with cloud access disabled. This proves the actual local boundary instead of assuming that a web dashboard or cloud API is equivalent to direct device control.
Frequently Asked Questions
Q1: Can Art-Net replace an LED sending card?
Normally no. Art-Net transports control data; the LED pixel path still needs a compatible processor/sending device and receiving system.
Q2: Does brightness and volume control always require an API?
Not necessarily. Preset scenes, software controls, serial or other interfaces may be available, but they must be confirmed for the exact model.
Q3: Does local control mean that no network is required?
No. Local Ethernet/Wi-Fi is still a network; it simply does not depend on the internet or a cloud service.
Q4: What if the manufacturer has not supplied an API document?
Collect the exact model, firmware, target functions and official protocol information. Do not guess commands; request confirmation or use a tested control method.
