The method of the SDRAM timing constraint in Nios

SDRAMs timing constraints are very important, when there is no timing constraints, due to the data pin-to-clock edge delay inconsistent, easy to lead to data sampling error,

Eventually the software fails to load, and it is common to find no chip ID in the software download process.

Below this method novice can refer to study!

The main point here is to talk about the clock constraints,

The main reference to the privileged classmates, links are as follows:

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The method of the SDRAM timing constraint in Nios