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Altera_Forum
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12 years ago

Is necessary megafuntion for used the plls?

Hi

For proportional signal clock to ddr memory using a pll of cyclone iii, it is necessary to use the megafunction altpll always? Or is it possible to connect directly to the pines of the plls without using the megafunction?

For example, if the clock in is 33 MHz and we want several signs of 33 MHz for other devices.

Regards

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    PLLs are dedicated FPGA hardware blocks. They are used in a design by instantiating alt_pll respectively altera_pll "MegaFunctions" and filling-in the required paraemeters. The most convenient way to do this is to use the MegaWizard tool. If you understand the meaning of all parameters, you can also instantiate the PLL directly in HDL code.