User guide

SYNCHRONIZATION

your Express interface freewheels at the frame rate it is

reading at the time it begins freewheeling — except for

29.97 drop and non-drop. If you intend on reading 29.97,

be sure to manually set the SMPTE format to 29.97 so that

freewheeling will occur at the proper rate.

When you increase the freewheel amount, you also

increase the amount of time that your Express interface

keeps converting when you stop tape. To make your

Express interface as responsive as possible, only raise the

freewheel amount as high as necessary to overcome the

drop-out(s) you are encountering.

Synchronizing to discontinuous time code

your Express interface has the ability to stay in sync with

discontinuous time code — that is, time code that has no

gaps in it but does have jumps in its frame locations. For

details about how to do this, see “Frame lock” on page 43.

SLAVING A SEQUENCER TO SMPTE

To slave a sequencer to SMPTE time code via your MOTU

Express interface:

1 Conﬁrm that the Express Interface is successfully

locking to incoming time code and transmitting MIDI

Time Code to the computer, as explained earlier in this

chapter.

2 Set up your software to slave to MIDI Time Code. While

doing so, you may need to direct your host software to the

Express interface Sync port, which is provided by the

driver. Consult your software documentation for details.

STRIPING TIME CODE

Along with its other capabilities, your Express interface is

a time code generator. It generates an audio form of

SMPTE time code called Longitudinal Time Code (LTC).

Use the procedure below to generate new code from

scratch:

1 Make the audio cable connections shown in Figure 2-6

on page 13.

!USB Interfaces Manual Book Page 58 Tuesday, August 16, 2011 11:21 AM