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Altera_Forum's avatar
Altera_Forum
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14 years ago

error in simulation

i have attached my code. error is during synthesis,it says that metavalue detected,turned to null.and gives null output.:cry:

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    Hi technovlsi,

    First this is my code not yours but you are welcome to use it.

    Is it simulation or synthesis that you produces error. Do use this module only or as part of larger project.
  • Altera_Forum's avatar
    Altera_Forum
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    @kaz sir,

    veryy sorry to declare this as my code,actuly sir,i got a big help from this forum.evryday browsing different peoples' problem,and solution given by u guys,are really helpful to a biggener of vhdl like me. however coming in the point,during simulation [sorry previously i told in synthesis] in the report window it tells that metavalue detected,turned to null.and gives null output,whatever value i have given. plz help.:oops:
  • Altera_Forum's avatar
    Altera_Forum
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    Hi technovlsi,

    You need to post more info. in fact you need to tell us about your testbench and how you are inputting into the LUT module. The LUT module itself has all its values defined right from reset. So it is likely your observation is wrong or the way you use the LUT.
  • Altera_Forum's avatar
    Altera_Forum
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    @kaz sir,in testbench,

    <reset : in std_logic;

    clk : in std_logic;

    clk_en : in std_logic;

    theta : in std_logic_vector(11 downto 0);>

    I GIVE RESET,CLK.CLK_EN ALL ARE 1,AND THETA = 60.GET NULL OUTPUT.

    -------- I CAN;T UNDERSTAND ABOUT UR "LUT" SUGGESION SIR.CAN U PLZ EXPLAIN?
  • Altera_Forum's avatar
    Altera_Forum
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    you cannot have the clock holding 1, it has to toggle, like a clock.

  • Altera_Forum's avatar
    Altera_Forum
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    clock should be toggled to get edge regularly (ofcourse)

    reset should be 1 initially then released to 0 otherwise you have to wait for ever.