Sirius 800 Series User Manual
Sirius 830: Video Crosspoint Arrangement
Crosspoint Modules 10.2
Iss 5 Rev 7
Page 161
© 2017 SAM
10.2 Sirius 830: Video Crosspoint Arrangement
The Sirius 830 has two horizontally mounted video crosspoint modules situated near the top
of the frame that send signals to the output modules. The lower module is the main video
crosspoint module, the upper module is optional and for redundancy. For video crosspoint
module locations see section 8.2.1.
The 288
2
router requires a minimum of one crosspoint module. The redundant crosspoint can
take the place of the main crosspoint module in the unlikely event of a failure. If the redundant
crosspoint has become active due to the failure of the main crosspoint, the system is no
longer redundant.
10.2.1 Sirius 830: Redundant Video Crosspoint Operation
The redundant crosspoint design is based around protecting against crosspoint module
failure. In normal operation, all the routes pass through the main routing crosspoint module.
The redundant signal path algorithm checks the signal paths on the main crosspoint module
in turn by configuring the redundant crosspoint module to mimic the main crosspoint module.
The algorithm compares the signal standard of each signal path through the main crosspoint
module with the signal standard of the equivalent path through the redundant module.
The algorithm also compares the signal lock status of each signal as it enters and leaves the
main crosspoint module. A difference between the incoming and outgoing signal lock status
indicates a route failure.
Each signal path is compared in turn until all of the paths on the main module have been
checked. Once all of the signal paths have been checked the algorithm repeats the checking
process.
If the algorithm finds a difference in the signal standard of a path passed by the main and
redundant crosspoint modules or if a signal lock status check fails for a route the failure is
flagged and the control system can (if configured) move the route to the redundant crosspoint
module. If more routes fail then they can also be moved to the redundant crosspoint module.
The algorithm will continue to check the crosspoint module for further failures. At this point the
crosspoint matrix is still capable of setting all 288
2
routes but redundancy protection has been
lost. This failure must be addressed immediately to regain redundancy for the crosspoint
matrix.
Additionally if any one of the following situations occur the router controller will move all
routes to the redundant crosspoint module:
•
The main crosspoint module is removed from the router.
•
The router controller looses communications with the main crosspoint module.
•
The crosspoint module reports one or more of its power rails has a fault.
To replace the failed crosspoint module all the routes on the failed module must be moved to
the redundant crosspoint module, see section 10.4.1 for details.
Example
:
Router pre-configured to move the failed route to the redundant crosspoint module.
•
Output 1 on the main crosspoint fails:
Output 1 on the output module switches to the redundant path
•
If Output 2 on the main crosspoint fails:
Output 2 on the output module switches to the redundant path
Note:
•
Any failure needs addressing immediately to retain protection, see section 10.4.1
for details.
