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problem about clock control block

Justin569
Beginner
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Hi,

When I use cyclone 10(10CL040YU484I7G)'s clock control block, I meet some problems.

In my application, there are 2 main clocks(one from clk pin and one from PLL), and 2 parts of main logic. I used 2 clock control blocks, and one for part A, the other for part B. But due to the inputs of 2 clock control blocks are same, Quartus says "Following nodes require the same Clock Control Block CLKCTRL_G10" in "place & route" phase.

Which logic will be chose which clock is only based on the clock chose logic. The clock chose logics of the two parts are independent. So I think I can't just use one clock control block.

I try to use LUT mux clock, but the quality of clocks are too bad to suit my application.What should I do? Why Quartus don't instence two Clock Control Block?

 

Thanks.

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sstrell
Honored Contributor III
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Are you saying that you've manually added the clock control block IP (twice) to the design?  Try just coding the clock enable logic without the IP and see what happens.  Quartus will (should) add clock control blocks automatically or whatever logic is required.

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Justin569
Beginner
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Hi sstrell, thanks for your attention. I directly used combinational logic for dynamical clock chosen before clock control block. But function didn't realised. Perhaps due to I hadn't constraint timming suitable. Nominally, the frequency of both master clocks is 125MHz. But the diffrence of frequency must exist. And they have diffrent phase. So I don't know how can I constraint the clock which chosen by combinational logic. Plase give me some guidance. Thank you.

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AqidAyman_Intel
Employee
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Since there is no response from you on the previous question/reply/answer that have been provided by the community user, please login to ‘https://supporttickets.intel.com’, view details of the desire request, and post a feed/response within the next 15 days to allow me to continue to support you. After 15 days, this thread will be transitioned to community support. The community users will be able to help you on your follow-up questions.



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