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Altera_Forum
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16 years ago

Quartus PLL - How to connect to existing VHDL

Hi!

I try to use the PLL function the first time and have some problems with it. It would be great if anyone could help me.

I used the MegaWizard PlugIn Manager to specify the PLL settings. But now I can't find out how to "connect" it with my existing VHDL program. I am using a Clk signal named "Osc" and I want to connect it to the PLL inclk0. Furthermore I need a Process with should reacts on the c0 PLL out.

I tried the following but I get the message "Error (10482): VHDL error at BX48.vhd(396): object "c0" is used but not declared". How can I access the c0 output from the PLL?

TestProcess: process (c0)

begin

if c0'Event and co = '1' then

--Todo...

end if;

end process TestProcess;

Details: Quartus 9.1, Cyclone III

Regards

Andre

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  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    The component name specified in the MegaWizard must match the component name used in the declarative part of the architecture. As I previously mentioned, both component definition and and instantiation template generated by the Megawizard should be copied.

    I'm sure, that you can figure out the right method by "trial and error". A VHDL text book or tutorial could be a shortcut, I think.
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    --- Quote Start ---

    The tip from "tricky" without the component specification works also. And it makes it even better in my eyes (no redundant specification).

    --- Quote End ---

    The great thing about this method is you dont have to wait until synthesis to find theres a missmatch between the component and the entity declaration; the compiler will pick it up really quick. Its quite easy to modify an entity and forget to update the component declaration - especially when you use it in several different files.