Syncing An Avb Network - MOTU 1248 User Manual

Figure 4-22: Settings for SMPTE time code sync.
LTC Input Source
Choose the input on your interface that is receiving
the time code (LTC). Any input can be used,
including an analog input, digital input or even an
AVB network channel.
Computer Channel for LTC-to-MTC Conversion
Choose a computer channel that you aren't using
for anything else here. It will be used to transmit
LTC from the interface to the computer. If all of
your computer channels are being used, you can
add extra channels using the To computer setting in
Routing setup (item 28 on page 21). See "LTC-to-
MTC conversion" on page 80 for further info about
LTC-to-MTC conversion.
LTC Format
Choose the frame format that matches the
incoming time code.
Enable Format Autodetect
If you would like your MOTU interface to
automatically detect the frame format of the
incoming time code, check this box.
H A R D W A R E I N S T A L L A T I O N
Enable Jam Sync
When this option is checked, your MOTU interface
will continue to convert LTC to MTC even after
incoming time code stops being received. Once
Jam Sync kicks in, it will continue generating until
you click Stop Jam Sync.

SYNCING AN AVB NETWORK

The AVB protocol provides sophisticated and
accurate timing, synchronization, and clocking
features for AVB device networks of any size as
shown on pages 44-45, including:
Low latency
■
Network-wide time base
■
Better-than-sample-accurate phase lock across
■
all connected devices
Timing accuracy down to the nanosecond
■
Choosing a master clock
The web app provides an easy way to choose one
device as the master clock for your whole MOTU
AVB network.
1 Go to the Devices tab (page 18).
2 In the device list (item #1 on page 18), choose
the MOTU interface you wish to use as the clock
master.
3 Click the Become Clock Master button
(Figure 4-23).
Now, all other MOTU AVB devices on the network
are resolved to this device.
Alternately, you can go to the clock mode menu for
each individual device separately and choose the
master clock device by hand. For example, you may
be in a situation where at least one MOTU device
on the network must remain resolved to its own
clock (or another clock source). Just know that in
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