# VHDL - Query about Division of two Nos

Discussion in 'VHDL' started by Bakkurudeen Ali J, Nov 24, 2004.

1. ### Bakkurudeen Ali JGuest

Hello All,

How can I perform division for the below mentioned :

Data_In : std_logic_vector(33 downto 0);
constant ZETA :std_logic_vector(8 downto 0) := "100100001";

Now : Result <= Data_in / Zeta;

I intend to represent the result rounded to (16,-7) (i.e., 9 bits
integer and 7 bits fractional)

NOTE: The Constant(ZETA) which I have mentioned is Canonical Signed
Digit Representation of An Integer value = -0.8710935

Kindly suggest me a solution to this problem !

Regards,
Ali

Bakkurudeen Ali J, Nov 24, 2004

2. ### Ralf HildebrandtGuest

Bakkurudeen Ali J wrote:

Wouldn't it be a good idea to use a multiplication? (Division by a
constant is the multiplication by the inverse of the constant.)
Multiplication by a constant can be reduced to some additions.

Ralf

Ralf Hildebrandt, Nov 24, 2004

3. ### Jim LewisGuest

Ali,
See the package IEEE.Fixed_Pkg:
http://www.eda.org/vhdl-200x/vhdl-200x-ft/packages/files.html

Since it is not yet standardized, you will temporarily need to
compile it into your own library to use it.

Cheers,
Jim
P.S.

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