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GHTE3 Transceiver Setup using ultrascale wizard

Thread Summary

The user encountered incorrect QPLL line rate values when using the Wizard for GTHE3 Transceiver settings with a line rate of 5.9904 GHz, QPLL0, and an actual ref clock of 149.76 MHz. The support engineer confirmed the correct settings should be QPLL0_FBDIV=80, QPLL0_REFCLK_DIV=1, and TXOUT_DIV=2, and suggested ensuring the files are properly updated or removed after deleting the IP in Vivado 2022.2. The user verified the correct values after following the advice.
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Category: Hardware

Hello,

Using the Wizard for the GTHE3 Transceiver settings seems to generate wrong values when checking with the manual line rate calculation for QPLL (https://docs.amd.com/v/u/en-US/ug576-ultrascale-gth-transceivers). 

I give this to the Wizard: 

Line rate = 5.9904 

PLL Type = QPLL0

Actual ref clock = 149.76

Encoding = 8b/10b

But, when i check the line rate using eq. 2-3 and 2-4 i get:  QPLL Line Rate = 1235.52

using these values from the generated files:

f_ref=149.76

QPLL_REFCLK_DIV=2

QPLL_FBDIV=66

TXOUT_DIV=4

So, my question is why do i see a difference?

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