Other Parts Discussed in Thread: USB2ANY
Hello,
We have a board with 4 DS90UB953 serializers connected directly (through caps) to a DS90UB960 quad deserializer. I'm using this setup to aggregate 4 CSI2 streams into a single stream for processor consumption.
Our real difficulty is in getting the 4 inputs sync'd, but I stepped back to test the interface using BIST. I don't think that BIST is running.
The UB953's are running with default settings. I have a USB2ANY board connected running Analog LaunchPad for configuring the UB960. I think my register settings are good because all 4 serializers are linked to the UB960 and FC and BC appear stable.
Reg 0xB3 was set to 0x83 for all 4 ports to enable BIST on the UB953's. According to Reg 0xD0 bit 5, all 4 serializers are in BIST mode. Reg 0xD0 bits 0 & 1 are supposed to inject errors into the back channel frame, I assume to test BIST. Setting bit 0 a few times, I go back and check the BIST error counter at reg 0x57. There are no errors. Setting bit 1 for continuous errors, bit 5 goes low indicating the serializer is no longer in BIST, and errors in reg 0x57 still don't go up.
At this point, I don't trust the error injector. So I take a ground wire and randomly touch it to the FPD-Link traces. The link goes down momentarily, but still no errors increment in the related BIST counter. So how do I know that anything is actually being sent and tested? I watched the 20 min training video twice. There isn't anything there that can answer this. I hope that you can. Thanks.
Darin
