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Cyclone 10LP DDIO extra one clock latency

ervoL
Beginner
210 Views

Hi!

 

I am using Cyclone 10LP to catch data from AD9257. Data and frame clock coming form ADC are LVDS signals and frame clock is connected on clock capable LVDS pins.

 

Frame clock is forwarded to PLL to generate fast clock. ADC data are connected to DDIOs running on this generated fast clock

 

Problem is extra latency of one clock that I have and I don’t know where does it comes from. On image below you can see frame clock, input data and generated fast clock. Now I would expect a case 1 where DDIO data is delayed for one fast clock regarding to frame clock but I have a second case with 2 clocks delay.

 

Does someone know what causes this extra clock delay?

 

Best regards!

0 Kudos
2 Replies
KhaiChein_Y_Intel
109 Views

Hi,

 

Can you provide the design for investigation?

 

Thanks.

Best regards,

KhaiY

ervoL
Beginner
109 Views

Hi KhaiY,

 

thank You very much for engagement.

Problem is meanwhile solved; it was a stupid copy paste mistake where I looked the data on the output of a register that comes after DDIO and that caused this one extra clock latency.

 

Best regards,

Lovre

P.S.  I was a little ashamed, so I didn't write in the forum that the problem was solved, but I will do that next time.

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