Contact HMS Store Manager

Goto HMS-Brightsign Home Page

Contact HMS Technical Support

HMS Home Logo

Brightsign RS232 Serial Interface to DMX



w/DMX512 Controller

New Rev2 Firmware

This board is used by the Brightsign to control a DMX Dimmer Pack or other DMX device.


Transmit Protocol: 170,DMX-Channel1, DMX-Channel2 to DMX-Channel40 (first byte has to be 170 (decimal).  When the 'decimal 170' byte is received, the board is ready to receive the DMX values.  IF the first byte of a transmission is not 170 (decimal), then the Hz-LED flashes at 3 Hz.

The DMX bytes have to be sent from the BrightSign as 'multiple serial bytes', no carriage return.  Use the BrightAuthor Command 'Serial-Send Bytes (comma separated)'.
I.E. to set channels 1-4 at 50% brightness send: [170,128,128,128,128].

Serial-DMX protocol: In order to reliably communicate with this board there has to be a protocol set.  There has to be a 20 millisecond 'Break' when sending 'data byte strings' to this board from the Brightsign. The Protocol is: [170, DMX Channel1 byte, DMX Channel2 byte, DMX Channel3 byte, DMX Channel 40] followed by 'BREAK'.  Any number of bytes can follow the 'start byte' of 170 decimal.

Note: If only channel 3 needs to be changed, then send channel 1 through channel 3.  (Only the channels preceding the channel that needs changing needs to be sent.

Fade Selection:  Fixed fade of 20 milliseconds for each 'brightness change' is set in firmware.  Use the following switch settings to enable fade.

Note: For more fade channels or for variable fade, use the HMS-RS232-DMX board.  

Updated: 12/04/2016