cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
Highlighted
Adventurer
Adventurer
3,795 Views
Registered: ‎03-15-2016

GTX Rx show radom data when not connected

Hi,

I found one confusing things during debugging the GTX,

when I discconect the GTX Rx, no coming signal on Rx. in chipscope, gt_rxdata_i,(gt_rxusrclk2) the parallel data, will shows radom data. e.g

5555555555555,  aaaaaaaaaaaaaaaa, 55a5a55a.....etc..

How could that happen?

 

Thanks

Caleb-

0 Kudos
3 Replies
Highlighted
Xilinx Employee
Xilinx Employee
3,775 Views
Registered: ‎08-01-2008

I think this is not random data.

The GTP receiver includes a built-in PRBS checker. This checker can be set to check for one of three industry-standard PRBS patterns. The checker is self-synchronizing and works on the incoming data before comma alignment or decoding. This function can be used to test the signal integrity of the channel



Thanks and Regards
Balkrishan
--------------------------------------------------------------------------------------------
Please mark the post as an answer "Accept as solution" in case it helped resolve your query.
Give kudos in case a post in case it guided to the solution.
0 Kudos
Highlighted
Xilinx Employee
Xilinx Employee
3,763 Views
Registered: ‎02-14-2014

Hello @jumper_qb,

 

Can you let us know the steps you followed which made you observe this behavior?

 

Regards,
Ashish
----------------------------------------------------------------------------------------------
Kindly note- Please mark the Answer as "Accept as solution" if information provided is helpful.
Give Kudos to a post which you think is helpful and reply oriented.
----------------------------------------------------------------------------------------------
0 Kudos
Moderator
Moderator
3,714 Views
Registered: ‎02-16-2010

Can you check if this is because of crosstalk? Can you probe RXOUTCLK output from GT in this scenario?
Whether this data is consistent? or found in some duration only.
------------------------------------------------------------------------------
Don't forget to reply, give kudo and accept as solution
------------------------------------------------------------------------------
0 Kudos