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Altera_Forum's avatar
Altera_Forum
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12 years ago

How can I use clock on cyclone II ?

Guys,

Do you know how to use a clock in cyclone 2 ?

Connect the PLL output into CLK0 ? and configure it on quartus ?

I tried to read on :

7. PLLs in Cyclone II Devices

But don't understand clearly on how to use it....

What's the simplest way to use get a clock on cyclone 2 ( EP2C8Q208)? in uC it's very simple for a clock source, a network of 2 capasitors and crystal....

Any links or eperiences will be appreciated.

Thanks

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    Hello bianchi.

    you don't have an oscillator in a Cyclone device so 2 capacitors and a crystal isn't enough. Electronics components stores like mouser or digikey have integrated oscillators. With Cyclone II i used an SMD 50MHz 3,3V oscillator of ABRACON.

    Configure the PLL it's easy. You have a Wizard to do it. Then you instantiate a component pll in your vhdl file. A detail: I use global reset active with '0' and the pll has reset active with '1'. Don't forget the inverter in your design or you'll see it hanged.
  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    --- Quote Start ---

    Connect the PLL output into CLK0 ? and configure it on quartus ?

    --- Quote End ---

    Lift you up by your own bootstraps? You're still missing a clock source for the PLL.

    As there's no inbuilt oscillator circuit, you would typically use a four-pin crystal oscillator device. Looking at a basic development kit schematic should give you an idea how.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    --- Quote Start ---

    Lift you up by your own bootstraps? You're still missing a clock source for the PLL.

    As there's no inbuilt oscillator circuit, you would typically use a four-pin crystal oscillator device. Looking at a basic development kit schematic should give you an idea how.

    --- Quote End ---

    So I need external clock source. Do u know the link of the schematic? Tx
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    --- Quote Start ---

    Lift you up by your own bootstraps? You're still missing a clock source for the PLL.

    As there's no inbuilt oscillator circuit, you would typically use a four-pin crystal oscillator device. Looking at a basic development kit schematic should give you an idea how.

    --- Quote End ---

    can I use this one ?

    http://www.ebay.com/itm/4-pcs-50-000mhz-dip-4-50-000m-50m-50mhz-crystal-oscillators-3-3v-/370804552950?pt=lh_defaultdomain_0&hash=item5655ac74f6

    Thanks