Phase Locked Oscillator

[LearnVHDL]

Dear All,

Here's what I want to build:

Input: clk with a X ns period

Goal: the period of the output clk is X ns * ( 1+ 1/256)
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How can I do that? I was told that I need use phase locked oscillator. But how? Can anyone give me more info on this? How to implement a phase locked oscillator with VHDL??

Thanks in advance...