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Setting for user_clk

Open ztachip opened this issue 1 year ago • 1 comments

I assume that user_clk is the clock for the AXI interface. Do I have a choice on this clock? Can I set user_clk to any clock value? Thanks

ztachip avatar Apr 23 '23 04:04 ztachip

Hi @ztachip,

user_clk is indeed the clock of the user interfaces. This is provided by the core and you have to use it for the user interfaces. It's possible to adjust this clk by setting sys_clk_freq but I would first recommend using a value closed to the one used in an example to start with and then do small change/test increments.

The variation range will be limited by:

  • The frequency range of the PLL used to generate this clk from the primary clk.
  • The frequency range of the DRAM.

enjoy-digital avatar Apr 24 '23 06:04 enjoy-digital