User manual

In this section:
Introduction to IEEE-1588 based triggering .................... 11-1
IEEE-1588 implementation in the Series 3700 ................ 11-1
Correlating PTP to Coordinated Universal Time (UTC) ... 11-2
Configuring and enabling IEEE-1588 .............................. 11-3
Monitoring alarms with LAN triggers and LXI event log ... 11-6
Introduction to IEEE-1588 based triggering
The Series 3700 uses IEEE-1588 Precision Time Protocol (PTP) to implement
synchronized measurements and initiate time-triggered events over the LAN
(Ethernet) interface. IEEE-1588 is a requirement of the LXI B Functional Class.
Using IEEE-1588, you can schedule instrument-driven actions, such as
measurements, to occur at a specific date and time and synchronize timebases
between instruments on the same network. You can only access these
capabilities through the remote command interfaces.
NOTE You can find detailed information on the syntax and usage of each ICL
command presented in this section in Instrument Control Library (ICL)
(on page 12-1).
IEEE-1588 implementation in the Series 3700
When you enable IEEE-1588 on a Series 3700 on a local network, the Series
3700 communicates with other IEEE-1588 enabled devices on the network
through a dedicated network port called the PTP port. A predetermined
algorithm then automatically selects the network device with the most accurate
clock. This network device becomes the IEEE-1588 master. If multiple devices
have the same clock accuracy, the protocol arbitrarily chooses one device to be
the IEEE-1588 master.
When the protocol selects the Series 3700 as the master clock, the Series 3700
uses the time value stored in its battery-backed real-time clock and updates the
time in all slave devices. When the protocol selects another networked device as
the master clock, the Series 3700 is slave to the more accurate device and
adjusts its time to that of the master clock. Additionally, the Series 3700 updates
its battery-backed clock so that the time is „remembered‟ if the master clock is
removed from the network.
Section 11
LXI Class B Triggering (IEEE-1588)