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Spirent KB Article
Doc ID: FAQ12855
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Spirent TestCenter: What connections are needed between the Chassis and the Symmetricom TP-5000 GPS receiver?
External Timing Reference - Symmetricom TP5000
When an external timing reference (ETR) is needed for GPS setup, 3 connections are needed.
AUX/CRAFT serial connection.
The two coax/BNC connections are for clock signals (10Mhz / 1PPS).
We should be using a Null-modem serial cable (Not a straight-through cable) which carries the time-of-day (ToD)
On the TP5000 unit/modules, the serial port is labeled 'CRAFT'.
Baud rate on the TP5000 'CRAFT' port should be set at 56kbps, if not already defaulted to.
You must also configure the Spirent TestCenter chassis to communicate with a TP5000 device.
This is done by the following steps:
Telnet or console to the Spirent TestCenter chassis (Console configuration is 9600-8-n-1 & No Flow control)
Enter 'etr device TP5000' (This ensures the chassis does not have to search for a device by using different baud rates and commands)
Enter 'etr devname' or 'etr device' (If we have "TP5000" returned, we can verify that the device was excepted by the chassis firmware)
If/when getting ETR status-related errors (i.e. 'Error: unknown status fe', 'Error while waiting for response'), please double check the 'AUX'/'CRAFT' connection.
If you connect to the TP5000 to the Spirent TestCenter chassis before setting the 'etr device TP5000' command, you may need to reboot the TP5000 and wait for it to lock/calibrate to the satellites again.
The first release of the Next Generation SPT-N11U chassis did not support the TP5000 yet. v4.31
Tested in v4.33 and TP5000 shows Successfully Established Connection.
Product : Chassis,Spirent TestCenter