chapter two
hardware and
installation
The
Programmable Show Controller (PSC) is a modified ETC Expression control
console configured with a Designer’s Worksheet digitizer tablet in place of the
Expression keyboard, and four, rather than two, faders. The system enables you
to use SMPTE time code to control cues and other effects.
Internal clock mode
During playback operation,
the system (either the PSC or RSC) processor
continuously compares incoming SMPTE time code with time data from its own
internal clock. If the system
detects time variations of plus or minus two frames,
it automatically adjusts the execution of cues to resynchronize itself with the
SMPTE time code it is receiving. If it detects variations of more than two
seconds, it
automatically switches to Internal Clock mode. In this operating
mode, the system
executes cues based on its own internal timing information.
When SMPTE input is restored, the
ESCS resynchronizes operation to the new
SMPTE time, and cues are once again controlled by incoming SMPTE time code.
This takes place when 30 consecutive, valid SMPTE frames are received. If the
flow of SMPTE code to the system
is stopped, it continues to run cues based on
its own internal timing until SMPTE input is restored.
