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Altera_Forum's avatar
Altera_Forum
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17 years ago

clock generation from cyclone3

hi,

i want to generate 216Hz clock from cyclone3 pll mega function with 8.192MHz as pll input , but pll is not supporting.

if i generated using logic elements is there any problem (with suitable i/p clock)?

is it possible to access all the 5 outputs of pll?

i hope u can help

thanks

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    I dont think you can get a 216MHz clock out of a 8.192 MHz input at all. At least not exactly. If you want to get close to it, you can try to cascade 2 PLLs, but not sure about JItter and clock quality.

    Lokla
  • Altera_Forum's avatar
    Altera_Forum
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    hi,

    please tell how to cascade plls in cyclone3

    regards

    krishnam raju
  • Altera_Forum's avatar
    Altera_Forum
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    Use the output clock signal of one PLL as input to the second PLL.

    Lokla
  • Altera_Forum's avatar
    Altera_Forum
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    hi..please tell how to write

    vhdl code for frequency divider with 50% duty cycle.

    regards
  • Altera_Forum's avatar
    Altera_Forum
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    Is this question somehow related to the original post?

    In any case, you can use a counter for that.