The DMX circuit expansion allows DART controllers to connect and control devices such as LED lights.
It is also possible to use the MIDI feedback function for MIDI to DMX conversion: as the machine receives a MIDI signal from an outside source (via USB or via DIN cables), the LED corresponding to the modifier that is set on the same message will light up, and the corresponding DMX output will be produced.
So, the MIDI to DMX conversion allows the user to program light sequences as easily as writing sequences of MIDI notes.
DMX config example
In this example we opened the Dart_ONE_default_preset on the DART_Editor and selected the item B17 (related to an Arcade pushbutton). In the Settings_Box on the left of the screen, the DMX_channel selector has been set up to value 11, so the pushbutton B17 will control DMX values on channel 11:
- the value 255 (maximum_value*2) on channel 11 will be sent out on Button_pushed condition.
- the value 0 on channel 11 will be sent out on Button_released condition.
- The DMX contol functionality is available for pots, buttons and distance sensors.
- The DMX value range is 0-255 (double of the common MIDI range, wich is 0-127), so the minimum/maximum values, that are defined for MIDI messages, are just multiplied by 2 for DMX operation.
- It is possible to access up to 64 DMX channels by default. The maximum number of channels can be increased by modifying this setting within the Sketch: DmxSimple.maxChannel(64);
DMX expansion circuit
|DMX circuit on breadboardDMX||DMX circuit on DART_MOBO|
DMX output – circuit components:
- 6N137 optocoupler
- SN75176 line transmitter
- NME0505 CC-CC converter
- 1x resistor 100 ohm
- 1x resistor 4,7k
- 1x resistor 470 ohm
- 4x 0.1 uF capacitors
- Cannon connector
DMX section assembly examples
SHOP : DMX output – Expansion kit