A DMX-512 network can be as long as a mile, or as short as a few
inches. The DMX-512 network needs to be one long line, with no long side
branches. If the network is longer than a few feet, you may need to provide
a terminating resistor at the two far ends of the network (120
Ω
,
½
Watt is
typically used). The resistors suppress ‘echoes’ on the DMX-512 wires.
If the network runs throughout a facility, it is prudent to use a some
isolated splitters. These will keep an electrostatic zap or lightning hit on the
network from damaging the entire network. An isolated splitter also allows
you to run side branches on the network, since each isolated branch is
treated as a separate DMX-512 network. DMX is daisy chained from the
output of the isolated splitter to the first ‘slave’, then from ‘Slave’ to ‘Slave’.
It can be run up to a mile, and may need its own termination resistors.
Addresses 256, 257, 511 and 512 are optionally used in GilderGear for
a checksum. The Br-EFB will automatically use this to verify that the data
received through DMX-512 has no transmission errors in it. If you address
a light dimmer or other DMX-512 device to addresses 256, 257, 511 or
512, you will see this verification data displayed as a flickering pattern.
Most GilderGear will automatically start requiring GilderChecksums after
receiving DMX-512 that has GilderChecksums in it. Once it starts requiring
GilderChecksums, the only way to get the Br-EFB to stop requiring it is to
cycle power on it.
Note that at higher frame rates, not all 512 channels can be transmitted
through DMX-512.
Gilderfluke & Co.• 205 South Flower Street • Burbank, California 91502 • 818/840-9484 • 800/776-5972 • fax 818/840-9485
Br-EFB Manual / May 22, 2018 3:28 PM / page 37 of 142
