Synchronization across a Network
The onboard 100 MHz oscillator automatically synchronizes to other network-synchronized
devices that are part of your local 802.1AS subnet.
The 80 MHz, 20 MHz, and 100 kHz Timebases are derived from the oscillator, and are
synchronized to it. Therefore, they are also synchronized to other network-synchronized
timebases on your 802.1AS subnet. This enables measurement signals to be synchronized to
other devices across a distributed network.
The FieldDAQ devices use the IEEE 802.1AS protocol over the network to synchronize.
These devices cannot synchronize over the network with devices that use protocols or
IEEE 1588 profiles other than IEEE 802.1AS.
More Information about Synchronization
The following documents will help you overcome typical hurdles in getting started with
synchronized measurements:
•
Synchronizing analog input FieldDAQ devices with NI-DAQmx in LabVIEW
—Visit
ni.com/info
and enter
fdaisync
.
•
Designing Ethernet measurement systems for synchronization, considering
topologies, masters, and third party devices
—If topology changes result in a device’s
master changing, executing tasks may be affected. Visit
ni.com/info
and enter
fdenet
.
•
How to achieve high accuracy measurements
—Visit
ni.com/info
and enter
fdsync
.
•
Synchronization accuracy explained
—Visit
ni.com/info
and enter
syncacc
.
Ethernet Ports and Networking
The Ethernet Network Interface transfers data between the FieldDAQ device and the network.
It gathers the data into TCP/IP packets that can be sent across the network and interpreted by
the host.
Note
Refer to
Setting up the FieldDAQ Device
or
Connecting to a Real-Time
Controller
for information about connecting the FieldDAQ device to a host
computer or host real-time controller.
Ethernet Ports
The FieldDAQ devices has two 8-pin X-coded M12 Ethernet ports—0 and 1. You can use a
shielded straight-through Ethernet or an Ethernet crossover cable with either of the Ethernet
ports to network your device to a computer host, NI Linux Real-Time controller, another
FieldDAQ device, or any network connection on the same subnet. Refer to
Topology Options
for more information about using these ports in various topologies.
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FD-11613 User Guide