Vanguard Managed Solutions Vanguard 342 Benutzerhandbuch
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About the Vanguard 342
Clocking Limitations Vanguard 342
Clocking Limitations Vanguard 342
Limitation
Listed below are the clocking issues relating to Port 3 of the Vanguard 342:
Vanguard 342 DCE INT --> VG6560/VG320/VG64xx EXT at 1.5 Mbps
When a Vanguard 342 Port 3 is configured as internally clocked and is connected to
a 6560/320/64xx which is configured as EXT clocked, and the Vanguard 342 internal
clock is configured at 1.5 Mbps, the link has clock slippage and CRC errors.
Workaround:Configure the VG6560/VG320/VG64xx port "Invert TX Clock" to
YES.
When a Vanguard 342 Port 3 is configured as internally clocked and is connected to
a 6560/320/64xx which is configured as EXT clocked, and the Vanguard 342 internal
clock is configured at 1.5 Mbps, the link has clock slippage and CRC errors.
Workaround:Configure the VG6560/VG320/VG64xx port "Invert TX Clock" to
YES.
Vanguard 342 DCE INT --> VG6560 SDB2 EXT
When a Vanguard 342 Port 3 is configured as internally clocked and is connected to
a SDB2 card on a Vanguard 6560 which is configured as EXT clocked, the link will
not come up. Workaround: Configure the Vanguard 6560 SDB2 port as INT clocked
and the Vanguard 342 as EXT clocked. Connect the ports with a crossover cable. The
DIM on the Vanguard 6560 SDB2 port should be in the DCE position.
When a Vanguard 342 Port 3 is configured as internally clocked and is connected to
a SDB2 card on a Vanguard 6560 which is configured as EXT clocked, the link will
not come up. Workaround: Configure the Vanguard 6560 SDB2 port as INT clocked
and the Vanguard 342 as EXT clocked. Connect the ports with a crossover cable. The
DIM on the Vanguard 6560 SDB2 port should be in the DCE position.
Vanguard 342 DCE EXTLP --> VG6560 SDB2 or SDB INT
When a Vanguard 342 Port 3 is configured as EXTLP clocked and is connected to a
SDB2 or SDB card in a Vanguard 6560, the link will not come up.
Workaround: Configure the Vanguard 6560 SDB2 or SDB port as INT clocked and
the Vanguard 342 as EXTLP clocked. Connect the ports with crossover cable. The
DIM on the Vanguard 6560 SDB2 or SDB port should be in the DCE position.
In general, configuring a DTE device as Internally clocked or a DCE device as
externally clocked or EXTLP are not recommended configurations.
When a Vanguard 342 Port 3 is configured as EXTLP clocked and is connected to a
SDB2 or SDB card in a Vanguard 6560, the link will not come up.
Workaround: Configure the Vanguard 6560 SDB2 or SDB port as INT clocked and
the Vanguard 342 as EXTLP clocked. Connect the ports with crossover cable. The
DIM on the Vanguard 6560 SDB2 or SDB port should be in the DCE position.
In general, configuring a DTE device as Internally clocked or a DCE device as
externally clocked or EXTLP are not recommended configurations.