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Altera_Forum's avatar
Altera_Forum
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10 years ago

Error 10251 - cannot fall outside the declared range

Hello,

i have got a little problem with array of registers.

This is error message:

--- Quote Start ---

Error (10251): Verilog HDL error at File.v(160): index 5 cannot fall outside the declared range [3:0] for dimension 0 of array "Modulator"

--- Quote End ---

This is simplified module with all lines corelated with array "Modulator": 


module File# (parameter LFO1B=4'b0101)(input  Modulator_LFO1B)
wire  Modulator ;
assign Modulator=Modulator_LFO1B;
endmodule

Do you know what is going on?

Kind Regards

L.

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    10 years ago

    modulator is declared as an array of four six bit (ie, [5:0]) values, indexed as 0, 1, 2, 3 (ie, [3:0]).

    Your default parameter value is asking for index 4'b0101 which is 5. 5 is greater than 3. QED.

    So either change the default value to be in range 0..3, or in the module instantiation override the default parameter value.

    OR if you really mean for the array index to be a four bit value then it should be declared as [15:0] instead: 

    wire  Modulator ;

    since array selects are index values MIN to MAX (or MAX to MIN) and not address field widths.

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