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Altera_Forum
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16 years ago

Floating point pachage

Hi, I need to use the Floating-point numbers and i have to compile “fixed_generic_pkg.vhdl” and “fixed_generic_pkg-body.vhdl” first, i'm using Quartus II 9.0 (32-bit) Thank you very much
Altera_Forum's avatar
Altera_Forum
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16 years ago

These are the IEEE fixed point packages. They define types and functions that make using fixed point numbers easier in VHDL. There is a similar floating point ppackage, but I wouldnt recommend using it for synthesis.

the fixed point packages mike life alot easier when perforimg mathmatical operations on fixed point: 


signal A : ufxied(4 downto -3); --3 bits fractional
signal B : ufixed(4 downto -3);  -3 bits fractional
signal AtB : ufixed(9 downto -6);
signal ApB : ufixed(5 downto -3)
process(clk)
begin
  if rising_edge(clk) then
    AtB <= A * B;
    ApB <= A + B;
  end if;
end process;