CHAPTER 3
Menu System
SHAPESHIFTER User Manual
21
Determining DMX Start Channel Assignment
There are 512 available channels on each DMX link divided among all the devices in a particular
link. A fixture must have a unique Start channel number in order to respond independently to
controller commands.
To determine each fixture’s DMX start channel in a link, identify the channel range of every fixture
on the link. Channel range is the number of consecutive channels a fixture requires. Each
SHAPESHIFTER fixture requires a block of 28 consecutive channels on a 512-Channel DMX link for
Reduced protocol user mode or 79 channels for Enhanced protocol. The Start channel is the first
number of a fixture’s channel range.
When setting the Start channel on a fixture, remember:
• A fixture’s physical location on the link does not have to coincide with the order of channel
range assignments in the link.
• The fixture’s channel range must not overlap any other device’s channel range on the link.
When two devices on the same DMX link have overlapping channel ranges, one or both
devices will be disabled or behave erratically. The single exception would be if two or more
fixtures need to respond to controller commands in exactly the same way. In that case, those
fixtures must be the same type (for example two SHAPESHIFTER fixtures) and must share
the
entire
channel range.
The notes in the following table show the various considerations in determining valid Start
Channels for fixtures on a 512 DMX link.
Fixture
Rig
Position
Fixture
Type
DMX
Channel
Footprint
DMX
Start
Channel
Channel
Range
Notes
First
SHAPESHIFTER C1
(Reduced Protocol)
28 channels
C001
1-28
The Start channel is the first channel
in a consecutive block of channels
assigned to a fixture.
Third
SHAPESHIFTER W1
(Enhanced Protocol)
79 channels
C029
29-108
Fixture can be assigned the second
block of DMX channels without being
the second fixture on the rig.
Second
Technospot
37 channels
C109
109-145
Avoid overlapping channels with
other fixtures
Fourth
Studio Spot
18 channels
C400
401-418
Every channel in the link does not
need to be assigned.