ETAS
Functional Description
ES523.1
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User Guide
23
5.5
Time Synchronization
The modules provide a global clock pulse to compare the measurement chan
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nels in a module network.
Modules connected to the HOST interface can synchronize the ES523.1 (SYNC-
IN). If no synchronization signal is received at the HOST interface, the ES523.1
acts as master module for synchronization.
The time synchronization unit of the ES523.1 master synchronizes the con
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nected modules via the Ethernet lines. The synchronization signal is relayed to
connected modules at the ETH1, ETH2 and ETH3 interfaces (SYNC-OUT). The
slave modules adapt to the clock pulse specified by the master module.
The periodic synchronization signal is superimposed onto the Ethernet signals
without affecting data transfer. This excludes the possibility of a phase shift
between the individual measure signals, even when measurements are taken
from different modules.
The data of all connected modules of the ES4xx, ES51x and ES6xx lines is
acquired synchronously (ETAS device synchronization).
5.6
"Wake-Up" Function
Energy consumption must be as low as possible when used in the vehicle
because the measuring equipment is powered by a battery. This is why the
ES523.1 module is equipped with a link signal detector for an automatic power-
saving feature at the following interfaces:
• HOST
• ETH1
• ETH2
• ETH3
• CAN1
• CAN2
Using the function "Wake-up", the module can automatically switch between
the operational states "Standby" and "On" and start the measurement autono
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mously after switch-on.
The ES523.1 and modules connected to it automatically switch to “Standby” if
none of these interfaces receive link signals for a particular length of time or the
host computer is powered off or disconnected. As soon as link signals are
received by at least one of these interfaces or the host computer is active once
more, the system automatically switches to “On” ("Wake-Up" function), thereby
automatically switching on the ETAS modules connected to the measurement
system.
NOTE
The automatic powering-on of the ES523.1 via the Ethernet wake-up is possi
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ble at any of the Ethernet ports.