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Contributor
Contributor
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Registered: ‎03-04-2016

GTY simulation with reset FSM: GTPOWERGOOD always zero

Hi,

currently I try to simulate my generated GTY transceiver.

In the documentation the following picture is provided:

GTY_doc.PNG

At first I do the GTTXRESET (using the 'gtwiz_reset_tx_pll_and_datapath_in') port.

After that I can see the TX RESET FSM is in state 'ST_RESET_ALL_TX_PLL_WAIT' ('sm_reset_all[2:0] = '011').

The QPLL0RESET is '1', too, after the 'ST_RESET_ALL_TX_PLL' state.

Now I would expect the GTPOWERGOOD goes high (over 50 ms simulation time) but it does not!

Obviously my PLL won't lock, because GTPOWERGOOD has to be high.

 

Here a snapshot of the TX RESET FSM in my simulation (time unit is in us; freerunning clock = 15 MHz):

Sim_TX_reset.PNG

 

Furthermore I've tried to reset the GTY using the 'gtwiz_reset_all_in' but without success. Again I'm stucking in state 'ST_RESET_ALL_TX_PLL_WAIT' with GTPOWERGOOD = 0 (over 50 ms simulation time).

 

Is there a further signal I have to drive for a GTPOWERGOOD indication?

Which issue in my reset control of the GT_WIZ - reset ports could cause this strange behaviour?

 

I'm using the Vivado 2018.3 version. Simulating with VCS-N-2017.12-SP2-4 (Full64) at Linux SuSe.

I've created all simulation libraries in Vivado for this specific VCS version

Best regards,

  Michael

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Moderator
Moderator
520 Views
Registered: ‎07-30-2007

Is it possible you are missing a reference clock to the GT or the freerunning clock input to the design?  This is unusual in that you should be creating an example design that will deliver a working example design simulation.  If you have done this simulation on your own you should be able to compare to the example design simulation.




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