Sep 282011
 
Converts between MIDI, DMX, RS-232 Serial and IRThe DecaBox Universal Protocol Bridge – Click to Enlarge

This firmware revision was commissioned by a Crestron systems integrator in Canada.  He needed to generate simultaneously generate DMX scenes and MIDI note commands from his Crestron controller, which only had an RS-232 output port.

Consequently, we designed a personality which combines features of the RS-232 to DMX Converter and the RS-232 to MIDI firmwares.  DMX commands are generated based on this human-readable ASCII syntax:

FAAA@BBB:CCC[cr]

  • Commands start with a capital ‘F’ character
  • AAA is a three digit DMX channel, range is 000-512. As only channels 1-512 exist in a typical DMX universe, channel 000 is used to select all channels.
  • @ is the ASCII ‘at’ character, hex 0x40
  • BBB is a three digit intensity value, range is 000-255
  • (:) is the ASCII colon character, hex 0x3A
  • CCC is a three digit value, range is 000-999, describing fade time in tenths of a second. One second is 010, twelve seconds is 120, etc.
  • [cr] is the carriage return character, decimal 13 or hex 0x0D.

EXAMPLE COMMANDS

Set channel 5 to 240 on a 2.5 second fade:

F005@240:025[cr]

Setting the channel to zero sets all 512 DMX channels to the specified value and fade time:

F000@255:010[cr] <—- Set entire to full, 1 second fade

F000@000:000[cr] <—- All channels to zero, instantly

Multiple channels may be set to higher or lower levels in the same command, allowing for simultaneous crossfades.  Channel:Value sets are separated by the comma (,) character.

Set channel 10 to full, channels 11-13 to 10, channel 8 to 50%, on a 2 second fade:

F010@255,011@010,012@010,013@010,008@128:020[cr]

MIDI Note messages (Note on and note off are three-byte sequences each, see here for details) are built using a simple five-byte syntax:

M 0xAA 0xBB 0xCC [CR]

  • M is the ASCII ‘M’ character
  • 0xAA is a single byte, relates to note type and MIDI channel
  • 0xBB is a single byte, relates to MIDI note number
  • 0xCC is a single byte, relates to MIDI note velocity
  • [cr] is the carriage return character, decimal 13 or hex 0x0D.

In Crestron control syntax, a single hex character can be sent by using the escape sequence /x.  Thus, the actual command looks like this

M/xAA/xBB/xCC/x0D

Other control systems will of course use different string structures, but the gist is the same.

When the dust settles, a single Crestron (or Extron, or AMX) system can generate crossfading DMX scenes as well as MIDI note information.

A few weeks after we delivered this system, we wrote to see how everything was working.  Quoth the client,

Actually the Decabox worked so well I entirely forgot about it! Basically there were four product reps on the floor, each had an IPAD. They could bring a client to any screen and punch up a video using the IPAD and walk the client through their pitch. Additionally every 10 minutes a master video would roll that spanned across all four screens for a 360 degree projection system.

The Decabox triggered each video through a Dataton Watchout system using MIDI and then triggered preset lighting for each video via DMX. I only needed to make a few minor adjustments in Crestron (MIDI pulse length).

Overall it worked brilliantly and was easily worth the cost. I will be recommending it whenever I can.

Bob, www.rlds.ca

 

Need something similar?  Let us know.  Always happy to help.

 

 Posted by at 9:03 pm

  5 Responses to “How to Generate MIDI and DMX Data From a Crestron Controller”

  1. […] looks, based on which section of the touchscreen was triggered.  Though the DecaBox has an internal DMX Scene Engine, the AMX programmers didn’t want to build lighting scenes channel by channel.  It was much […]

  2. Good afternoon!
    My name is Pavel.I’m from Russia.

    Need information about The DecaBox Universal Protocol Bridge.
    Are there any you have for sale?
    What is the cost?
    What is the cost of transportation and delivery time, if the destination of Hamburg?
    I ask you to reply as soon as possible.

    Thanks a lot.

  3. Privet Pavel… Yes, we have plenty of stock available. 6-10 day shipping through the post office is $38. This is insured and trackable online. We can also ship using FedEx / UPS. This service is usually 2-5 business days, and price would be in the $130 – $160 range for freight.

  4. Good afternoon!
    I ask you to provide information that you have: signal converter from format RC-232 to MIDI.
    Need to a Crestron control system to control audio mixer, which control input is only MIDI
    What is his value?
    How much will it cost transportation to the destination in Hamburg?
    How soon can you send to us after payment?

    Paul.

  5. Pavel – check your email for details.

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