RS-232 / DMX512 Control Box
Preferred range of use:
The RS-232 / DMX512 Control Box was developed with a view of integrating lighting technology into multimedia projects, stand-alone media controllers or industrial controls.
It can be operated as a DMX transmitter and as a DMX receiver simultaneously.
The merge feature combines the DMX transmitter with the receiver:data received at DMX IN are multiplexed with user generated DMX levels to be retransmitted at DMX OUT. Some priority modes are selecetable.
Specific level changes at DMX IN can trigger ASCII text formatted state messages or user preprogrammed strings to be sent at the RS-232 interface.
In contrast to proprietary control equipment the RS-232 / DMX512 Control Box can be operated with any kind of software which is capable to transmit and receive via a serial COM port.
Primarily all commands are sent and all feedback is received in ASCII text format. As an alternative to ASCII syntax, the most essential features of the box can be operated with a compact binary data format, which provides a higher throughput and easier handling together with some kind of control application.
The range of use is not restricted to Windows-, Linux- or Macintosh computers. Suitable serial ports are available at many handheld devices, industrial controls or special hardware based media controls.
This way the DMX lighting bus is easily integrated into applications, which support serial ports together with a scripting language. Office applications can be used for control, too, if appropriate DLL libraries are added.
In a most simple case - especially to set up or debug lighting installations - manual interactive operation is possible with a simple terminal program.
In addition to the preferred data rate of 115200 baud, 57600, 38400, 19200 and 9600 baud may be chosen with the rotary switch "Select".
The actual lighting scene is buffered internally. It is permanently transmitted at the DMX bus until it is modified by another command. Interruption of the RS-232 connection has no influence on the DMX bus pattern. After power cycling or turn of the rotary switch, automatically preset no.0 is loaded.
Activity and mode of operation is monitored with a red/green dual colour LED.
This interface is intentionally kept simple: only the lines RxD, TxD and signal ground are necessary. At certain positions of the rotary switch "Select" RTS/CTS hardware handshake is activated
At pin8 (standard CTS handshake out) a regulated voltages +5V is permanently fed out (max.300 mA at 9V supply voltage, derating). This simulates permanent readiness to receive commands. On the other hand it is usable to supply external Wifi, Bluetooth and other radio modules. Upon request we assemble the box with a 9 pin "male","DCE" wired SubD connector and +5V out at pin9, which complies better with some commercially available radio modules..
The most essential features of control:
- Any DMX channel 1 to 512 can be set to any level by sending a short sequence of ASCII text to the box (8 bit of resolution). Binary commands are implemented as a more compact alternative.
- Additionally combinations of RGB colors may be set at 3 subsequent DMX channels with simple ASCII text commands.
- For any DMX channel a fade transition can be executed automatically, duration programmable up to 31.9 seconds. This diminuishes the expense for design of complex lighting sequences considerably. Any number of fade processes can be active simultaneously on all DMX channels.
- The flexibly configurable chaser feature loads sequences of presets (=lighting scenes) automatically in a cyclic manner to DMX OUT. Softly faded transitions are possible. The flash feature pushes all DMX channels to a defined level for a short period of time.
- The cycle of DMX data packets can be set by command between 24 and 512 channels. If a DMX channel out of the active DMX cycle is adressed, the packet length is readjusted automatically.
- The RS-232 / DMX Control Box is able to simultaneously receive a signal at DMX IN and transmit a different signal via DMX OUT. The signal transmitted at DMX OUT can be generated by several modes of operation:
--- transmission with DMX clock generated inside the box,
--- transmission externally snychronized with the received DMX signal and
--- receive & readout operation while the received DMX signal is looped to the DMX OUT connector.
- The merge method can be set individually for each DMX channel. Following options are available:
--- user settings loaded via RS-232 are transmitted at DMX OUT,
--- the sigal received at DMX IN is retransmitted at DMX OUT,
--- the less one , the greater one
--- or the last changed one of both is transmitted.
Please note that "merge" means slot-by-slot switching between both signal sources, not linear superposition.
- One ASCII command can poll the levels of 1 to 128 DMX channels of the recently received or transmitted DMX packet via RS-232 interface. An alternative polling method transfers bigger blocks of bytes in a more compact binary format.
- Automatic state messages can be programmed individually for each DMX channel. If the received DMX signal on a sensitized channel has changed more than a programmable threshold, the present DMX level is reported automatically via RS-232.
These messages are sent in the same format which is used by level setting commands. I.e. this feature is useable as a simple DMX recorder (but the capacity of the RS-232 line sets a limit to the number of channels which may be recorded simultaneously).
- Messages of freely defineable strings: If the DMX channels 500 to 512 receive specific levels at DMX IN, strings preformatted by the user (ASCII text, binary or both mixed) are transmitted automatically via RS-232. Up to 104 different strings, each max. 255 bytes, may be stored permanently and held available.
These can be used for control or configuration of external devices with RS-232 interface like video beamers or professional DVD players. The feature can be used for more sophisticated command input to PC-based user software, too.
- The actual state of the RS-232 / DMX Control Box (indluding transmit buffer, merge profile, thresholds for automatic messages, mode of operation, system configuration) can be saved permanently as a preset (=lighting scene). Up to 384 presets can be stored and be reloaded at any time.
The transition from the previous lighting scene is performed with the actual fade time.
During power-on and after turn of the rotary switch preset no.0 is loaded automatically.
equiped with 5 pin XLR connectors in compliance with the DMX standard.
(optionally available with 3 pin XLR connectors or with an 8 pin detachable clamp)
The DMX transmitter as well as the DMX receiver is galvanically isolated from the control processor.
If the application demands a ground referenced DMX transmitter, the optoisolation can be bridged with an internal jumper.
An in-plug adaptor for 230V AC with "europlug" is delivered along with the DMX Control Box. For special applications, other supplies with regulated or unregulated DC output can be used (min. current output 250 mA). The optimum supply voltage is 9 Volt, but up to 16 Volt are permitted.
Rugged aluminum case.
Mechanical dimensions: length about 9.5 cm (incl. connectors), width 11.3 cm, height 3.1cm.
Similar products made by Cinetix:
- Similar features offers the Ethernet / DMX512 Control Box, which is controlled by TCP or UDP ethernet packets instead of RS-232.
- To control and analyse a DMX bus by means of MIDI channel messages, we supply the MIDI / DMX512 Control Box. Additionally, this device offers features to trigger a broad range of MIDI messages by special levels at DMX IN.
- For applications of computer based lighting control, which don't need the receive and merge features, the RS-232 / DMX512 Generator offers a compact and low cost solution.
Manual of the RS-232 / DMX Control Box (PDF file)
* State of information October 2012. Right of technical modifications reserved.
* This description is for information only, no product specifications are assured in juridical sense.
* Trademarks and product names cited in this text are property of their respective owners.