Alcorn Mcbride Digital Binloop HD, User Manual

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Alcorn McBride Binloop User’s Manual Page 14
SMPTE Mode
There are 3 basic modes that the SMPTE Interface can operate in. It
can be configured to
Read timecode, Generate timecode, or generate
timecode in reference to the Binloop’s video clocks ( Generate /w V-
Sync ).
In Read mode, the SMPTE module will listen for incoming timecode
on the Binloop’s SMPTE In connector whenever the SMPTE module
is enabled. While operating in this mode, the SMPTE Interface will
repeat the incoming timecode on the SMPTE Out connector.
In Generate mode, the SMPTE Interface will generate timecode when
it is enabled (or started). This timecode is used internally, and is also
generated on the SMPTE Out connector.
The Generate /W V-Sync mode operates exactly like the normal
Generate mode, except that the SMPTE clock is generated
synchronously with the vertical sync video signal of the Binloop. For
example, if the Binloop’s A/V Sync system is configured for NTSC
(29.97fps), the SMPTE module can generate 29.97fps timecode that
is perfectly synchronous. This means that each ‘tick’ of the SMPTE
clock will coincide with the beginning of each video frame, even after
a long period of time. This feature is useful when you want the
SMPTE clock to remain in perfect sync with a video presentation, or
with an external video sync source.
SMPTE Times
The Preroll, Start, and End times are all used by the SMPTE Interface
when it is programmed to generate timecode. This graphic
demonstrates how these times are used by the generator.
As you can see, the timecode starts running from the Preroll Time
when the SMPTE Interface is first enabled. The timecode then
continues to run until the End Time is reached. What happens at this
point depends on the next setting; Loop Mode.
Loop Mode
The Loop mode setting determines what the timecode generator does
when the End Time is encountered. If the SMPTE module is
configured to loop, the timecode jumps back to the Start Time. If loop
mode is disabled, the timecode stops running.