Alcorn Mcbride 1746-SMPTE, Руководство пользователя

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Using the Module as a SMPTE Generator 9
SMPTE
Generator
Frame Rate
The generated SMPTE frame rate is determined by this 3-bit field.
Bit 0/10 Bit 0/9 Bit 0/8
30 fps 0 0 0
29.97 fps non-drop 0 0 1
29.97 fps drop 0 1 0
25 fps 0 1 1
24 fps 1 0 0
23.976 fps 1 0 1
The other two codes (110 and 111) are reserved for future use.
Loop Start, End Times
When the SMPTE output reaches the Loop End Time, it immediately jumps to
the Loop Start Time if the LOOP bit is set, or halts if the LOOP bit is clear.
Any invalid entries, such as minutes greater than 59, will be treated as if the
entry were zero. An error bit will be set in the Input File to highlight the
problem field.
Loop Behavior
If the LOOP bit is set (one), then when the SMPTE output reaches the Loop End
Time, the generator will jump to the Loop Start Time and continue generating
from there. If the LOOP bit is clear (zero), then the SMPTE output will stop at
the Loop End Time. Notice that by setting the Loop Start Time equal to the
Loop End Time, the module can be made to generate a continuous, unbroken 24
hour long loop of time code. Also, the Loop Start Time need not be smaller than
the Loop End Time. Time code rolls over at 23:59:59:29, so the End Time will
be reached eventually.
Mute Behavior
If the MUTE bit is set (one), then the SMPTE output is muted. Time code can
continue to be generated internally, but the output does not send the code. It is
as if the cable has been unplugged. If the MUTE bit is clear (zero), then the
SMPTE output sends whatever time code is being produced internally.
Dropout Tolerance
Only the SMPTE reader uses this word. It may be set to any value when
generating time code; the module will ignore it entirely.