Overview Of Precision Time Protocol Mode (Ieee 1588); Ptp Master Clock Identity; An Example With Two Nano Cameras - Teledyne m640 User Manual

Overview of Precision Time Protocol Mode (IEEE 1588)

PTP Mode = Precision Time Protocol
The PTP protocol synchronizes the Timestamp clocks of multiple devices connected via a switch
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on the same network, where the switch supports PTP.
For optimal clock synchronization the imaging network should use one Ethernet switch. Daisy-
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chaining multiple small switches will degrade camera clock syncs.
Additionally the Ethernet switch connecting cameras to the imaging network should implement
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"PTP Boundary Clock" hardware.
To use a multi-port NIC adapter or computer with multiple NIC ports instead of a switch, that
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multiport NIC must be capable to be configured as the common Master PTP source for all its
networks. Such a configuration requires using the multi-port NIC's configuration software.
Genie Nano cameras can automatically organize themselves into a master-slave hierarchy, or
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the user application configures a camera master with n-number of slaves. The auto-
configuration process typically happens within 2 seconds.
The automatic organizing procedure is composed of steps (as defined by IEEE 1588) to identify
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the best clock source to act as master. When only Nano cameras are used, since they are
equal, the last selection step is to identify the Nano with lowest value MAC address to be the
clock master.
The feature TimeStamp Source is automatically changed to IEEE1588 when PTP Mode is
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enabled. This timestamp tick (in ns) cannot be reset by the user.
• The Genie Nano cameras implement additional features designed to synchronize multiple
camera acquisitions via IEEE 1588 (PTP Mode) – not via external camera trigger signals.

PTP Master Clock Identity

The clock ID of the current best master is an Extended Unique Identifier (EUI)-64 "64-bit ID",
converted from the 48-bit MAC address, by inserting 0xfffe at the middle of the MAC address.
The standard MAC address in human-friendly form is six groups of two hexadecimal digits as
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this example shows (excluding spaces): "0a 1b 2c 3d 4e 5f"
The Extended Unique Identifier format is (excluding spaces): "0a 1b 2c fffe 3d 4e 5f"
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An Example with two Nano Cameras

The following basic steps configure two Nano cameras connected to one computer via an Ethernet
switch, configured with two instances of CamExpert, to grab a frame every second, controlled by a
modulo event via PTP.
For each camera set features as follows:
I/O Controls — select Trigger Mode=ON, Tigger Source=Timestamp Modulo Event
Event Controls — select PTP Mode=Automatic
Note how one Nano automatically becomes Master while the other becomes Slave
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Event Controls — to have a modulo event every second, set Timestamp Modulo
Event=1000000000
Click Grab on each instance of CamExpert. With the two cameras aimed at the same moving
object, you see that each camera grabs a frame at the same time.
166 • Operational Reference
Nano Series GigE Vision Camera