Question

I have a 2 D matrix where each element should be 64 bit std_logic_vector.

Now I want to store certain values into the matrix as shown in the below manner. How do I do that?
For example:

type a is array (0 to 10,0 to 10) of std_logic_vector(63 downto 0);
signal a1: a;
a1(0,0) <= std_logic_vector( to_float64(12.23) );

Basically I dont know how to convert float64 to std_logic_vector.

I am using float_pkg library from ieee_proposed.

Answer 1

Why not do:

type aftype is array (0 to 10,0 to 10) of float64;
signal af: aftype;

Then there’s no conversion.

In terms of conversions, the to_float function requires a type to know how to format the real input:

signal f : float64;
f <= to_float(12.34, f);
-- or
af(0,0) <= to_float(12.34,f);

If you must have a std_logic_vector, you can use to_std_logic_vector from the package (aliased to to_slv):

a1(0,0) <= to_slv(to_float(12.34,f));