SNLS589B September 2016 – July 2018 DS90UB960-Q1
In synchronized forwarding, the forwarding engine may be programmed to send only one of each synchronization packet. For example, if forwarding from all four input ports, only one FS, FE packet is sent for each video frame. The synchronization packets for the other 3 ports are dropped. The video line packets for each video stream are sent as individual packets. This effectively merges the frames from N video sources into a single frame that has N times the number of video lines.
In this mode, all video streams must also have the same VC, although this is not checked by the forwarding engine. This is useful when connected to a controller that does not support multiple VCs. The receiving processor must process the image based on order of video line reception.
Example Synchronized traffic to CSI-2 Transmit port at start of frame:
FS0 – S0L1 – S1L1 – S2L1 – S3L1 – S0L2 – S1L2 – S2L2 – S3L2 – S0L3 …
Example Synchronized traffic to CSI-2 Transmit port at end of frame:
... S0LN – S1LN – S2LN – S3LN – FE0
All packets would have the same VC ID.