Honored Contributor II
08-11-2017 06:59 AM
Hello everyone,I am trying to send SD-SDI signal through the GXB pins of my altera development kit. I have successfully implemented the Tx part and am able to see the test patterns on the display. However, when I am trying to loop this data back to the Rx, I am getting random 10 bit data output. I simulated the code with seriallpbken and it works perfectly fine there, but not on hardware. When I send the SDI data, I oversample it 5 times to make the data rate as 1350 Mbps to get it in the range of transceivers, and I can see 270 Mbps data at the output of Tx. The Rx gets this 270Mbps data back and has a CDR ref frequency of 135Mhz. So I'm not sure how Rx would oversample it 5 times again before deserializing. Even when I remove this loopback from Tx to Rx I am getting some random data which I am checking through signal tap, so I am not sure where this data is coming from. So, if anyone has worked on sending and receiving oversampled data using transceiver native phy, please help.