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any value conversion to 32 bit vector form in vhdl...please help

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dksagra

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hi, please help me out...

i have a constant value let A:=9
now i have to convert into digital form...
as we know in digital we can write this 00000000000000000000000000001001 for 32 bit data...
another example i have A:=34
we can write this 00000000000000000000000100010

i want this type of conversion (any number into 32 bit vector form)in VHDL...
please help me out..its too urgent
 

Bit vectors can be either signed or unsigned numbers. Use ieee.numeric_std conversion functions to_signed() or to_unsigned() respectively.

Reviewing some of your posts, I'm under the impression that you most urgently need the lecture of a VHDL text book.
 

yes u r right...thanks...
may be my understanding is not that good, but those who are good in any area they wont underestimate others..
i m accepting m not good in vhdl...but this is not a way to treat to beginner...

nevertheless, thanks a lot for ur deep concern...
 

FvM said:
Bit vectors can be either signed or unsigned numbers. Use ieee.numeric_std conversion functions to_signed() or to_unsigned() respectively.
Click to expand...
It is only possible to control the 31 lowest bits with to_unsigned() since it takes a natural as argument, and the tools normally restrict this to 31 bits.
Higher bits will be '0'.
 
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    FvM

    FvM

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It is only possible to control the 31 lowest bits with to_unsigned() since it takes a natural as argument.
Click to expand...
At least with Altera Quartus, unsigned numbers between 2**31 and 2**32-1 are also accepted and correctly converted, e.g.
Code: 
to_unsigned(4294967295,32);
 

FvM said:
At least with Altera Quartus, unsigned numbers between 2**31 and 2**32-1 are also accepted and correctly converted, e.g.
Code: 
to_unsigned(4294967295,32);
Click to expand...

It doesn't work with the Modelsim simulator. The maximum argument for to_unsigned() is 2147483647. This is also the expected behavior for all VHDL implementations that use 32 bits for the integer type (31 bits for type natural).

(the forum has lost all posts since yesterday, so some earlier posts in this thread has been lost)
 

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