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constant value in VHDL

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energy_baz

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hi,

Can I use this way to declare all my value for the constant because i need to use all these value in the same name.? Any idea how can I declare all these value in the same name..?
 
Last edited:

hi
Constant is a NON-varying value, if one name has different values it is a Variable) use array, if you dont want to change name. select_mod(1):=3, select_mod(2):=5 ...
 
I'm not sure how to use the variable....is this the correct way..?
 
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In fact, an integer constant can take only one value. Array of integer is a common solution to select between values.

Code: 
CONSTANT FREQ_SEL_MAX : integer := 13;
TYPE FREQ_PAR IS ARRAY (0 TO FREQ_SEL_MAX) OF INTEGER;	
CONSTANT SEL_PWM_DIV    : FREQ_PAR := (
      12000, 10000, 8000, 6000, 5000, 4000, 3000, 2500, 
      2000, 1500, 1250, 1000, 500, 200);

P.S.: You have to declare an array type to make it work.
 
A constant in any programming language is a value assigned to a specific name,
when you have an integer constant then it can only have one value.
You can use an array of integers if you want

Code VHDL - [expand]
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TYPE SAMPE_main IS ARRAY (1 to 10) OF INTEGER;
CONSTANT SAMPLE : SAMPLE_main := (10,20,30,40,50,60,70,80,90,100);
 
--to use it
 
SAMPLE(0);
SAMPLE(1);
-- etc

Alex
 
I noticed a bad habit to edit your original posts, deleting the code examples that the other contributions are referring too. In my opinion, it's a serious disregard of the forum members effort to solve your problems - and a pretty strong hint to keep away from it in the future.
 

FvM : I have to delete all the codes immediately because it might cause me plagiarism for my project. That's the reason why I'd deleted all those codes. Sorry about that.
 

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