cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
cseamans
Observer
Observer
778 Views
Registered: ‎11-05-2019

RF Data Converter DUC Not Working

Hi,

I am trying to use the digital up-converter/mixer within the RF Data Converter IP, but I do not achieve any mixing or up-conversion. In my block diagram I have a constant wired to the nco_freq pin (say for example: 200MHz), and another constant wired to the nco_update_en (with value 0b000111). Am I missing another constant to be wired or some logic?

Thanks

0 Kudos
5 Replies
pthakare
Moderator
Moderator
738 Views
Registered: ‎08-08-2017

Hi @cseamans 

In addition to this you have to assert nco_update_req for a clock cycle (s_axi_aclk)

Please refer to the NCO update diagram in the product guide. https://www.xilinx.com/support/documentation/ip_documentation/usp_rf_data_converter/v2_2/pg269-rf-data-converter.pdf  page 135

Capture.JPG

 

-------------------------------------------------------------------------------------------------------------------------------
Reply if you have any queries, give kudos and accept as solution
-------------------------------------------------------------------------------------------------------------------------------
cseamans
Observer
Observer
629 Views
Registered: ‎11-05-2019

Apologies for the long delay in response. I got the the nco_update_req toggle going into the IP, but I still do not see an upconverted output. I send in 100MHz samples, and I set the nco_freq to 1GHz, but still the output of the board is 100MHz. Using the ILA I have made sure that the request signals are not being sent until after the busy signal deasserts. I'm not sure how else to debug this problem. Do you know of any other reasons why it may not be working?

0 Kudos
pthakare
Moderator
Moderator
600 Views
Registered: ‎08-08-2017

Hi @cseamans 

Before a NCO update , you have set the event source to tile .

There is "Dynamic Update Events " section in PG269 starting from page 102

https://www.xilinx.com/support/documentation/ip_documentation/usp_rf_data_converter/v2_2/pg269-rf-data-converter.pdf

 

 

-------------------------------------------------------------------------------------------------------------------------------
Reply if you have any queries, give kudos and accept as solution
-------------------------------------------------------------------------------------------------------------------------------
cseamans
Observer
Observer
582 Views
Registered: ‎11-05-2019

When does the dacXY_pl_event have to be asserted? Just one clock cycle before the update request, or earlier? Does it need to be held high a certain amount of time?

0 Kudos
pthakare
Moderator
Moderator
378 Views
Registered: ‎08-08-2017

Hi @cseamans 

The dacxy_pl_event need to be asserted before the update (before nco_update_req)  and need to keep asserted while update is happening.

Update is completed when nco_update_busy  deasserted.

-------------------------------------------------------------------------------------------------------------------------------
Reply if you have any queries, give kudos and accept as solution
-------------------------------------------------------------------------------------------------------------------------------
0 Kudos