cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
jliu83
Adventurer
Adventurer
2,783 Views
Registered: ‎06-26-2008

Datapath only for EDK Pcores

I have a AXI based core that has two clocks.  Clock crossing are taken care of with FIFOs.

I'd like to drive the internal core with 133Mhz, and the video with 100Mhz.

 

I understand that I need use the "datapathonly" keyword so that only the datapath is analysed but the example in UG216 is not very helpful.  Is the following correct?

 

NET "aclk" PERIOD = 133 Mhz HIGH 50 %;

NET "vid_clk" PERIOD = 100 Mhz HIGH 50 %;

NET "aclk" TNM_NET = "tn_aclk"; 

NET "vid_clk" TNM_NET = "tn_vid_clk";

 

#can I use 133 MHz instead of 7.518 ns here?

TIMESPEC "TS_a_to_vid" = FROM "tn_aclk" TO "tn_vid_clk" 7.518 ns DATAPATHONLY;
TIMESPEC "TS_vid_to_a" = FROM "tn_vid_clk" TO "tn_aclk" 10 ns DATAPATHONLY;

 

In addition I'd like to keep a UCF file with the pcore.  I guess it is also possible to keep this within the EDK's UCF, but the design would be more modular if the UCF can be kept with the pcore.  Is this possible, and how would I go about doing such a thing.

 

Thanks in advance for the help.

-J

 

0 Kudos
2 Replies
siktap
Scholar
Scholar
2,695 Views
Registered: ‎06-14-2012

Yes this is right. You could add directly to system.ucf

 

TIMESPEC "TS_axistreamclks_2_axi4liteclks"  = FROM axistream_clk  TO axi4lite_clk 20000 ps  DATAPATHONLY;  #assumes axi4lite_clk <= 50 MHz

  TIMESPEC "TS_axi4liteclks_2_axistreamclks"  = FROM axi4lite_clk   TO axistream_clk 6667 ps  DATAPATHONLY;  #assumes axistream_clk <= 150 MHz

0 Kudos
htsvn
Xilinx Employee
Xilinx Employee
2,668 Views
Registered: ‎08-02-2007

Hi,

 

To keep a UCF along with the pcore, you might want to use generate_corelevel_ucf that is available in the most EDK IP's.

 

Check the snapshot attached for an example. 

 

--HS

 

UCF_Generation.png

----------------------------------------------------------------------------------------------
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