SOPC with SDRAM Contoller

--- Quote Start ---

Do you mean that I cant separate the clock for CPU and the clock for SDRAM?

--- Quote End ---

You can use a separate clock for sdram with same or different frequency.

I meant you however need a separate clock for driving the external sdram clock pin, because you must apply the phase shift.

So, in a general case you have 3 clocks:

- cpu_clk

- sdram_clk, connected to sdram controller inside sopc builder

- sdram_ext_clk, same freq as sdram_clk but -1.5ns phase shifted; this only connects outside to sdram clk pin.

--- Quote Start ---

I made a calculation based on the formula on the user guide, which lead to -1.46 ... and do you mean minus 1.5ns?

--- Quote End ---

Yes. Minus means a phase lead as I told you.

So my -1.5 guess was good!