For Brightsign Units (or computer) with USB Port

DMX512 with 'HMS Protocol'

      
HMS-USB-DMX Board

HMS Firmware Protocol DMX512 Controller

Features:

• Footprint (4.8 x 2.8 inches) (USB-B Connector)
• Diagnostic Mode (Cycle DMX) and 'Options' selectable on board
• On board LED's to indicate BrightSign Power and Processor running.
• Serial Setup: 38400 baud, N,8,1 (Use these settings for the Prolific USB-Serial converter)
• Individual DMX Channels can be set using the new 'Command' structure.
• Special 'Channel Set Commands' to enhance 'DMX Head' controlling.
• Firmware Upgrade/Custom using a computer and the 'HMS Down Loader' program.
• 48 'Scenes' available for programming (175 scenes by special request)

Description of Operation:
This board is used to interface to any BrightSign with a USB port. 

Serial Transmission 'Break' Protocol:  The USB port (BrightSign) has to allow 20 milliseconds to elapse between serial data 'bursts' going out.  This 20 millisecond 'rest' time is interpreted by the HMS board as a 'Break' in serial transmission.  This 'Break' condition synchronizes the HMS board to the serial transmissions from the BrightSign (or other device).

New Command Selection for HMS Protocol:  The first byte received by the HMS board (after 'break condition') sets the receive protocol command.  This new protocol simplifies how many bytes to send from the BrightSign because the DMX parameter is selectable! The bytes are enclosed in brackets [ ].  Note: 'Speed' = Rate of Fade.

Note: See the 'Not HMS Protocol' for simple DMX control (no fade) near the bottom of this specification sheet.

• Command 0 thru Command 15 are not applicable to this board (no outputs)
  
  *********DMX SPECIFIC COMMANDS 16-30 (HMS Protocol) Updated 06/01/2015
  Firmware version 3.30 Limits minimum fade to 12.  IF less than 12, then fade is set to zero to prevent exceeding the limit of the DMX dimmer box.
  Tested on 60Hz line, the minimum may need to be slightly greater than 12 for 50 hz line.
  
• Command16:  Set DMX Channel Values (Starts at Channel 1)
  ? bytes             [16, #Bytes, DMX_CH1 to DMX_CH100], followed by 'Break' if '#Bytes' was not received
  
• Command17:  Set Multiple DMX 'Fade Channel' values
  ? bytes             [17, #Bytes, Channel#,'Channel Value', 'Fade Value', Channel#, 'Channel Value', 'Fade Value',....], followed by 'Break' if '#Bytes' was not received.
  
• Command18:  Set 1 DMX 'Fade Channel'
  4 bytes             [18, Channel#, Channel Value, Fade Value]:   *1  End Command
  
• Command19:  Set all 24 DMX Fade values to one value
  3 bytes             [19, Fade Value,204]  *1  End Command
  
• Command20:  Set the 24 DMX 'Fade Channels' to a pre-set Fade Speed (values have to be in Channel order!)
  25 bytes           [20, Ch1_Fade Value, Ch2 Fade Value,... to Ch24_Fade Value], followed by 'Break' unless all 24 Fade values are sent
  
• Command21:  Set 1 or more DMX channels to a value. 
  ? bytes             [21, #Bytes, Channel#, Value, Channel#, Value....], followed by 'Break' if all the bytes ('#Bytes') was not received
  
• Command22:  Set 1 DMX channel to a value:  New: With Version 3.1 firmware setting channel 0 sets channel 256
  3 bytes             [22, Channel#, Value]   *1  End Command
  
• Command23:  Set all DMX channels to one value (channels 1 to 255)
  3 bytes             [23, Channel Value,204]  *1  End Command
  
• Command24:  Set all 24 DMX ' Fade' channels to one value (channels 1-24)
  3 bytes             [24, Channel Value,204]  *1  End Command
  
• Command25:  Set all DMX 'Non Fade' channels to one value.  (Channels 1-24 depends on options 1-4), and channels 25 to 'Max Channels'
   3 bytes            [25, Channel Value,204]  *1  End Command
  
• Command26:  Set DMX Channel#, first byte to this channel, successive bytes to successive channels.  Well suited to DMX Head Controlling!
  ? bytes             [26, #Bytes, Start Channel#,  Value1,  Value2, more values to #Bytes], followed by 'Break' if '#Bytes' was not received.
  
• Command27:  Set Default Fade Value for Power-up (Value stored and retrieve at power up)
  3 bytes            [27,Fade Value, 204]
  
• Command28:  Set All DMX Channels off Instantly (Does not affect the Fade Values)
  2 bytes             [28,204]
  
• Command29:  Set the maximum number of DMX channels to transmit (the default is 50).  This value stored in permanent memory.
  3 bytes            [29,Max Channels, 204] Note: with Firmware 3.1 all 256 channels can be set.  *See 'DMX512 and Fade' note below.
• Command30:  Set 1 upper DMX channel (Channel 256 to 511)  Note
  3 bytes            [30, Channel#, Value] Note: Channel#=0 is channel 256.  Channel# = 255 is channel 511) (add the channel number to 256 to set set the upper channel number).
  
• Command31:  Set the upper channel 'start channel',  successive bytes to successive channels.  Note: If using a 'play command' the 'successive channels' have to terminate with a '204' byte
  ? bytes            [31, start channel, value, value, value....]  This command terminates with a 'break' protocol.
  

*********Play/Record and Other 'Scene' Commands 32-36

Link to 'Scene Format (Protocol)'

• Command32:  Play 'Recorded' Scene' to the computer (see also the HMS Scene Editor)
  3 bytes             [32, Scene# (1-48), 204] Note: Contact HMS Electronics for a 175 scene board.
  
• Command33:  Record 'Scene' (256 byte limit) (Scenes can be concatenated)
                          [33, Scene# (1 to 48), 204, 1 to 512 bytes] Note: Contact HMS Electronics for a 175 scene board.
  
• Command34:  Cancel 'Play Scene'. This command should be issued prior to any new command if Command32 was last command.  This insures that the 'Play Scene' Command is stopped.
  2 bytes             [34, 204]
  
• Command35:  Erase Scene (erase all scene bytes)
  3 bytes             [35, scene#,204]
  
• Command 36: Set DMX Scene (3.1+ firmware).  This 'scene' command sets the channels from a scene up to 'max channels'.  This scene for DMX can be set using the 'Record Scene' command above.
  3 bytes            [36,scene#,204]
• Command 37 (firmware 7.1+ only!):
  3 bytes          [37,1,204]  This command sets the DMX-512-Flag.  (Only required once after power-up)
   Firmware 7.1 has this new command that sets the 'DMX 512 Flag'  This feature allows for concatenate of two successive scenes, The second scene will play up to 'Max Channels (see Command 29).  I.E. You the 512 flag is set, then you use Command 36 to set scene number.  Then both scene# and the next scene are transferred to the DMX channels.
  

********Miscellaneous Commands (Useful for Development)

• Command 39:  Say "Max Channels = ",max channels.  This command sends the text of 'max channels' to the serial port and the text of the variable 'max_channels'
   
• Command43:  Send the Data for DMX channels 1 to 'Max Channels' to the Serial Port
                        [43,204]
  
• Command44:  Send 'Scene Data' to Serial Port:  All 256 bytes of the scene are sent out the serial port. Very useful for verifying command 'data strings'.
  3 bytes             [44, Scene# (1 to 48), 204]
  
• Command45:  Report the Software version of the board to the Serial Port
  2 bytes             [45,204]
  
• Command46:  Report the Goals and Fades for the Fade channels.  I.E. Goal 1, Fade 1, Goal 2, Fade 2,....to Fade 24
  2 bytes            [46,204]
  
• Command47:  Firmware Upgrade Command (the HZ LED will flash at 3 Hz) (use the 'HMS_Downloader.exe' program)
                          [47,204]

*1: 'End Command' means that this was the end of the command and another command can be part of the same string (no 'Break' required) 
I.E. Turn on DMX channel 1 100%, Turn on DMX channel 50 100%   [22,1,255,22,50,255]  (Two command22's in succession)

Notes:

• Any 'Command' followed by a 'break condition' terminates the Command. So, if zero bytes follow Command=16, Command 16 will simply be terminated at the break condition.
• If you use 255 for the #bytes, then the command will be terminated at 'Break' and fast flashing (Hz LED) will indicate that the command did not terminate correctly (#bytes was not received).
• The brackets are not part of the byte sequence!  Send decimal bytes no strings!
• If #bytes is less than the bytes you are sending as part of the protocol, unexpected results will happen.  
• Any 'illegal' command results in 'dumped bytes' until 'Break' condition.  So, if a large string of bytes is sent, and a channel fade number is out of range (>16), then the remaining bytes of that string are discarded.
• To 'Concatenate' Scenes:  see 'Scene Format Protocol'

To Send Multiple Commands (not concatenated) , Send 1 command, then pause for 10 milliseconds, then send the next command and pause and so on except where designated above.
I.E. if selecting Command12 (Set all 16 DMX fade values): Note if all 16 values are sent then the next Command can be part of the string.
I.E.  [15,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,'new Command#','bytes for that Command]

Note: Fast Flash of the 1Hz LED (3 Hz).  When any command is terminated with 'Break', fast flashing occurs.  When a command is sent incomplete or out of range, (I.E. set fade for channel 30), because channel 30 is out of range, fast flashing is set.  Fast Flashing is cleared upon complete reception of a command not requiring the 'Break' condition.  I.E. Send 'Command0', to clear the fast flashing after 'Break'.

DMX512 Operation:  The DMX first 4 to 'Max Channels' channels (see command31) are sent every .8 seconds if Option2) or whenever the DMX 'Channel' bytes change (resulting in instant DMX output).  The DMX512 protocol is so fast that the entire 256 (256 channels) channels of DMX data can be sent out during 12 milliseconds.

DMX512 and Fade:  In order to get good fade action, the 'Max Channels' should be set to maximum of 24 channels.  It takes about 1.2 milliseconds to send 24 channels.  So if 48 channels is selected, it takes 2.4 milliseconds to send the channels.  Then, the brightness can only be 'adjusted' every 2.4 milliseconds (not every millisecond).  The DMX bytes are sent out immediately after a brightness change (caused by a 'fade' change).

DMX 'Head' Operation.  If a DMX dimmer pack is utilized, setup the dimmer pack to utilize channels 1-4.  Then set the DMX 'Head' start channel to 5 (or whatever channel is allowed).  If the DMX 'Head' is the only DMX device, then set the 'Head' channel to channel 1.  If the DMX 'Head' protocol expects to receive 20 bytes (20 channels) then all 20 of those bytes need to be sent with each DMX 'Head' command sequence.  Likewise, when using the BrightSign to control the DMX Head, the BrightSign should send all 20 DMX bytes with each Serial Send() command. If the DMX512 'Head' can only be set for 'even addresses' or multiples of a number (I.E. 20,40,60) then the bytes for that address (channel) will have to start at the address or channel set as the base channel.

DMX 'Play Scenes'.  A 'scene' file can be created and stored on the SD card.  BrightScript would be used to interpret the 'scene file'.  Any number of scenes could be stored on the SD card.  Contact the BrightSign people if you need help with this programming.

DMX_Demo.AVI (84 mega byte movie demo)                    DMX_Demo.mov 6MB (requires Quicktime)    Link: Setting up the Serial Port and Sending Bytes with 'BrightAuthor'.

USB-DMX-Cycle.brs (sequences channels 1 thru 8 on). Rename this file to 'autorun.brs' and put it on the SD card

*****************************************************************

• Options (Rev6 Firmware):

  • SW1-1 Off = HMS Protocol enabled (uses the command structure explained above).
  • SW1-1 On = HMS Protocol disabled. The byte sequence is [ DMX_CH1_byte, successive DMX channel bytes]
  • SW1-2 On  = Repeat DMX continuous.
  • SW1-2 Off  = Send DMX bytes every .8 seconds or as the DMX bytes change (commands or brightness changes due to fade).
  • SW1-3 On = 115,200 baud
  • SW1-3 Off = 38,400 baud
  • SW1-4 On = Cycle Diagnostics ( Turns DMX channels 1-100 full on, then off every 2 seconds).

  Note: Fade Command makes 'Fading the lights on and off' an easy task if utilizing a DMX Dimmer Pack.  To Fade up lights just output 0xFF ( 255 decimal) for the channel value for DMX Ch 1 to 24)  To Fade down the lights, just output a zero (decimal) for the channel value and the brightness will Fade down at 20 millisecond intervals or at the rate specified with the speed setting.

  Note: Fade Speed: The Fade speed value is the number of milliseconds to increment (increase brightness by '1') or decrement (decrease brightness by '1') of the channel value.  If the channel value is 255, and the speed value=20, then it takes 20 milliseconds for each step or 5.1 seconds to obtain full brightness (0 to 255).  If the Fade Speed is zero, the new channel value is output immediately to the DMX channel.  So if the channel value was 0, then 255 and the speed value is 255 (255 milliseconds per step of 1),  then it will take 65535 milliseconds (255 times 255) to finish Fade (1092 seconds).  You may want to keep the value below 50.

Not HMS Protocol:

With Option 1 on (SW1-1) the 'Not-HMS Protocol' is used.  Instead, a simple protocol is used and no Fade!  This protocol uses the 20 millisecond 'break protocol'.  After 20 milliseconds the pointer is reset to DMX channel 1.  To set channels, just send the 4 bytes for the 4 channels (or more bytes if more channels).

Note: Fade Command makes 'Fading the lights on and off' an easy task if utilizing a DMX Dimmer Pack.  To Fade up lights just output 0xFF ( 255 decimal) for the channel value for DMX Ch 1 to 24)  To Fade down the lights, just output a zero (decimal) for the channel value and the brightness will Fade down at 20 millisecond intervals or at the rate specified with the speed setting.

Note: Fade Speed: The Fade speed value is the number of milliseconds to increment (increase brightness by '1') or decrement (decrease brightness by '1') of the channel value.  If the channel value is 255, and the speed value=20, then it takes 20 milliseconds for each step or 5.1 seconds to obtain full brightness (0 to 255).  If the Fade Speed is zero, the new channel value is output immediately to the DMX channel.  So if the channel value was 0, then 255 and the speed value is 255 (255 milliseconds per step of 1),  then it will take 65535 milliseconds (255 times 255) to finish Fade (1092 seconds).  You may want to keep the value below 50.

*****************************************************************

New 'AutoRun' Feature version 7.x firmware.

With firmware 7.0 and up, there is a new feature that enables 'auto run' of a scene.  This feature will allow running of a 'scene' on power up.  Scene 48 is dedicated for this purpose.  If scene 48 is setup as 'play scene' command, then that scene is 'played' on power-up. This means that you can set any DMX scene to 'play' when power is applied.  This is useful when 'stand alone' use of the board is required (no BrightSign to control it).

Scene 48: Set scene 48 to run another scene using the 'Play Scene' command.  Scene 48 is checked on power-up to determine if 'Auto Play' is enabled.  I tested this feature using Scene 47 to initialize the 4 first channels of DMX.

Scene 48 set as follows: 32,47,0,204 (play scene, scene47, loop-count = 0, 204 (verify byte).  Use command 33 to record scene 48.  I.E.  33,48,204,32,47,0 (note the 204 is the verify byte of the command, the scene bytes follow).

Example Scene 47:
First set up default fade (if required), then initialize the first 4 DMX channels.  This is done with two 'concatenated' commands.  First command (set default fade) is 19,0,204,170 (command 19, fade 0, 204 'varify byte',170 'end command'.  The second command is 'set successive DMX channels' (command 26)  I.E. 26,4,1,255,255,255,255,170.  Command 26, 4 channel bytes to follow, starting channel (channel 1), 4 channel values, 170 = end command.
Use command 33 to record scene 47:  I.E. 33,47,204,19,0,204,170,26,4,1,255,255,255,255,170.  Note: you can skip the 4 bytes of command 19 if you don't want to set the default fade.

Note: If SW1-1 is on (option 1) (not HMS Protocol), then the 'AutoRun' feature is disabled on power up.  This 'bypass' is provided in the event that the 'record scene' caused a 'lockup' of the program.  You can turn the switch back off after power-up to re-enable 'HMS Protocol' so that the recorded scene can be reviewed.  I provided this feature because I forgot to use the 170 to indicate 'end of command'.  So I got 255 for minutes of pause!

Last Revised: 03/02/2024