Controlling the UDMR with MIDI signals
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Using time codes to sync operation with external devices
Definition of MTC & LTC
MTC (MIDI Time Code)
MIDI information used to accurately synchronize MIDI devices
with industrial tape recorders and video equipment etc. Unlike
the MIDI click clock, MTC is displayed in absolute time. The
master device transmits the current absolute time (elapsed
hh/mm/ss/frames) while the slave device puts its clock forward
to match said time. In order to use MTC, the other devices
must support MTC syncing.
Playback of the UDMR's DMX phrases can be synchronized
with digital mixers and visual equipment etc. by combining
MTC and MMC signals.
LTC (Longitudinal Time Code)
A transceived signal stipulated by the Society of Motion
Picture and Television Engineers (SMPTE) which is used
synchronize multiple audio and video devices. LTC indicates
the position from the starting point in the 'hh:mm:ss:frames'
format.
Playback of the UDMR's DMX phrases can be synchronized
with digital mixers and visual equipment etc. by combining
LTC and MMC signals.
Time code types (frame rates)
The time codes (frame rates) which can be selected with the
UDMR are as follows. To synchronize operation using
MTC/LTC, it is necessary to match the frame rates of both
devices. Check the specifications of the external MIDI device
to be connected before configuring the time code.
Frame
rate
Summary
30
30 frame/sec non-drop format
Used with audio devices such as analog tape
recorders and NTSC black & white videos.
29N
29.97 frame/sec non-drop format
Used in NTSC color videos.
29D
29.97 frame/sec drop format
Used in NTSC broadcast color videos.
25
25 frames/second.
Used in SECAM/PAL video & audio devices and
movies.
24
24 frames/second.
Used in U.S. video & audio devices and movies.
Drop frame & non-drop frame
NTSC video cassette recorders use two types of time codes,
namely the discontinuous 'drop frame' time code and the
continuous 'non-drop frame' time code. The drop frame time
code omits the first two frame numbers of each minute (except
minutes 00, 10, 20, 30, 40 and 50) in order to support NTSC
color videos.
Non-drop frame (29N)
Drop frame (29D)
In standard video and music production, the non-drop frame
time code is used because frames are easier to handle when
they are continuous. On the other hand, the drop frame
method is used in broadcasting where the time code must
match actual 'wall clock' time.
When loop playback of phrases is set to 'ON', the playback
may fail to synchronize with MTC. If this occurs, change the
loop playback setting to 'OFF'.
CAUTION
