One way of combining multiple camera streams is to use a serializing and deserializing (SerDes) design. The CSI-2 data from each camera is converted by a serializer and transferred through a cable. The deserializer receives all serialized data transferred from the cables (one cable per camera), converts the streams back to CSI-2 data, and sends out an interleaved CSI-2 stream to the single CSI-2 RX interface on the SoC. Each camera stream is identified by a unique virtual channel. This aggregating design offers the additional benefit of allowing long-distance connection of up to 15m from the cameras to the SoC.

The FPD-Link or V3-Link serializers and deserializers (SerDes), supported in the AM6x Linux SDK, are the most popular technologies for this type of CSI-2 aggregating design. Both the FPD-Link and V3-Link deserializers have back channels that can be used to send frame sync signals to synchronize all the cameras, as explained in [7].

Figure 2-2 shows an example of using the SerDes to connect multiple cameras to a single AM6x SoC.

Figure 2-2 Connecting Multiple Cameras Using SerDes

An example of this aggregating design can be found in the Arducam V3Link Camera Solutidon Kit. This kit has a deseralizer hub which aggregates 4 CSI-2 camera streams, as well as 4 pairs of V3link serializers and IMX219 cameras, including FAKRA coaxial cables and 22-pin FPC cables. The reference design discussed later is built on this kit.