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

OP #2501217
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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
Moderator (Company: Titel) #2501241
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Try this:
1
library IEEE;
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use IEEE.STD_LOGIC_1164.ALL;
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use IEEE.NUMERIC_STD.ALL;
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:
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signal vector std_logic_vector(31 downto 0);
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:
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vector <= std_logic_vector(to_unsigned(34,32)); -- here your value 34 is converted to a 32 bit vector


BTW:
WHERE does this value come from?
And whats your actual problem?
I ask this because I think you asked the wrong question...
OP #2501257
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thank you so much...
its a long program...
if u want to have a look than i can send...but u understand my logic 
right...

but the value of A changes very instant of time...
cant we put directly A inplace of 34
means
vector <= std_logic_vector(to_unsigned(A,32));
like wise...

regards
Moderator (Company: Titel) #2503431
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1
--error is here-"Operator <INVALID OPERATOR> must have constant operands or first operand must be power of 2
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K_temp := "0100000000000000000000000000000000" /A ;
Oooops, a divider. Is this design for a FPGA?

You can simulate a division easily.
But if you want it to run on real hardware, you will get immediately 
into trouble, if the divisor isn't a power of 2 (like 2, 4, 8, 16, 
32...).

Because if the divisor is a power of 2, then the division is just a 
different wiring inside the FPGA. Thats easy, and its done by the 
synthesizer on its won.

If the divisor is not a power of 2, then the division gets fairly 
complex. You then usually involve a divider-core, plus you will have to 
read a manual of at least 20 pages...   :-o


BTW:
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Use IEEE .numeric_std .All ;          -- take his one
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use IEEE.std_logic_signed.all;        -- or those old osolete ones here
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--use IEEE.std_logic_unsigned.all;
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use IEEE.std_logic_arith.all;
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                                      -- but never all of them together!!!

BTW2:
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-- ***********************
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--* Begin main process . *
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-- ***********************
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Begin
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Process ( z_position , reset ) Is
1. There is no "main process". Every process has the very same 
proirity, because every process will be synthesized to hardware.

2. The reset is absolutely unnecessary. Because even with reset='1' the 
reset-values of x and P will be overwritten immediately in the first two 
lines after the "end if;".

BTW3:
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x :=
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("00000000000000010000000000000000",
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"00000000000000010000000000000000");
For better readability try this:
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x := (x"00010000",x"00010000");
Or this:
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x := (to_signed(65536,32),to_signed(65536,32));

BTW4:
>>> Begin main process
This whole design looks like you are "thinking in software", this will 
not lead to a solution for a language that "describes hardware"!
OP #2503451
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So what to do now?
should i use ipcore?
or one thing is in my mind, tell me is it possible
in K_temp := "0100000000000000000000000000000000" /A ;
first i convert "0100000000000000000000000000000000" into integer
and then convert A into integer..
then divide both bcoz they are in integer now..
after that the resultant of the divison be converted back into signed...

please help me out..

thanks

best regards
Moderator (Company: Titel) #2503460
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> or one thing is in my mind, tell me is it possible ....
> then divide both bcoz they are in integer now..
Absolutely NO.
Because casting and converting does not change one thing at the fact:
you want to do a division.

You're tricking around and hoping for a hidden way.
That will not work here...

> should i use ipcore?
I think you will have to. And: read ALL of the documentation.

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