8 bit Data Byte Explanation:
A basic computer data byte (hence forth referred to as 'byte'), is 8 bits wide and holds a maximum number of 255 decimal. The 8 bits are numbered bit0 to bit7. Each bit is a logic '1' or a logic 'zero'. If the bit is set to logic '1', then that 'bit 'number' is added to get the total value of the byte in decimal. As you can see by the 'Bit-Binary-Decimal' Table below if all bits are set and you add all the bits together the maximum number is 255. Note: Logic 1 is the same as 'on' and Logic 0 is the same as off in BrightAuthor.
Here is a table of 'bits' and equivalent decimal values.
Just add the decimal numbers together to get the bits set on that you want. Setting all bits on is 255d (decimal).
I.E. Setting bits 0 and 7 on is 128+1 or 129 decimal. To set multiple colors, set the color# to the combination of bits.
This new HMS Protocol for controlling the DMX is optimized for quick change to DMX channels with minimum overhead. This new protocol lets you select a DMX channel to change. If you need to change the value for channel 16, it only takes 3 bytes to perform the task instead of sending all 16 channel bytes. Or, if not setting fade value, it only takes 2 bytes to set any DMX channel value.
How to set Minimum 'Start Voltage' for Incandescent Lights or Motors:
This applies to the 16 DMX channels that have fade control! If you want to
set a voltage (power level) to start at one power and then increase to the
'power level' set in the set DMX Channel & Fade, then this is how to do
that.
First, send an instant power setting to a Fade Channel (fade=0). Use
Command18 (Set 1 DMX Fade Channel). Then follow this command with another
Command 18. I.E. [18,16,40,0], this command sequence will set fade channel
16 to value of 40 and instant change (fade=0). Then the next command to
the same channel will set the 'finish voltage' and fade rate.
[18,16,200,20]. So, the whole sequence will be
[18,16,40,0,18,16,200,20]. This is all you need to send to get the DMX
channel to start at power level of 40 and fade up to power level of 200.
BrightAuthor Notes:
Port 0 is the serial port (if available on the BrightSign)
Port 1 is the TTL port (this is the port that sends data to the HMS board). Don't forget to set the baud rate in the control panel!
Port 2 is the USB-Serial port. If connecting USB-Serial chip (this chip is on all HMS 'USB' boards) then the HMS board appears as Port2. If using a port expander (to get multiple USB ports), then you will have to determine the correct Port to set in BrighAuthor
At 'events', you want to select 'Send Data' as the event, to port2, and then record the bytes there that you want to send to the HMS Board. If you use my new developer tool 'RS232 to BrightSign TTL' you can use your computer to view the bytes send by the BrightSign or, you can use your computer to send the control strings to the HMS board.
Setting the TTL Port in BrightAuthor:
1. Select 'Edit', then 'Preferences' on the main menu.
2. Select 'Interactive', Port=1, Baud 38400, Data bits=8, Parity='none', Stop
Bits=1
updated: 02/17/2011