A__mic8 / A__digital8 User Guide
Version: 10.0.0/4
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6. Synchronization
A__mic8 / A__digital8 as PTP Master
When operating as a PTP master, the A__line device transmits PTP
to
the streaming network via both of its
interfaces: ETHERNET A and ETHERNET B. The reference clock for the PTP signal can be selected using the
RAVENNA Web UI. For the A__mic8, you can choose either Internal or WCLK IN. For the A__digital8, you can
choose Internal, WCLK IN or AES3 In 1.
PTP clock source options (A__mic8)
PTP clock source options (A__digital8)
To generate PTP from an external reference, the clocking signal
MUST
match the internal sample rate of the
device.
A__mic8 / A__digital8 as PTP Slave
When operating as a PTP slave, the A__line device locks to PTP received
from
the streaming network via either of
its interfaces: ETHERNET A and ETHERNET B. The device's sync source must be set to PTP using the
RAVENNA Web UI (as described
).
Installing a Grandmaster Device
If you wish to install a third-party PTP master device, then Lawo recommends Meinberg clock generators.
Alternatively, for networks utilizing SMPTE 2022-7, you could install a Lawo A__madi4. This brings a number of
advantages:
·
A__madi4 can transmit PTP to the network via both of its interfaces. Thus supporting the two separate
network paths required for SPS.
·
A__madi4 provides two independent bridges. Thus it can provide redundancy for the PTP clock source.
To implement this solution, the A__madi4
must
be clocked to a reliable Wordclock signal. Lawo recommends
Rosendahl Wordclock generators.
Checking the PTP Sync Status
Once all of the streaming devices and connected and configured, the PTP sync status can be checked from the
"
" area of the RAVENNA Web UI Home page.
6.3
Non-PTP Installations
If PTP is not available and all devices support syntonised streaming, then you can use external Wordclock as the
sync reference for all streaming nodes.
To support this option, you must have ordered the Wordclock version of the A__mic8 / A__digital8 and have a
reliable Wordclock signal that can be distributed to all nodes on the network.
Please note:
·
For correct synchronization without PTP, the same sync source
must
be selected at all streaming nodes!
·
All nodes
must
support syntonised streaming. This is true for all Lawo RAVENNA interfaces, but must be
checked for third-party devices.
