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library ieee;
context ieee.ieee_std_context;
use ieee.math_real.all;
entity direction_mismatch is
port (
left : out std_logic_vector(1 to 0)
);
end entity direction_mismatch;
architecture rtl of direction_mismatch is
constant c : std_logic_vector(1 downto 0) := "01";
-- function that can flip words around the center axis of an SLV
-- ex. input=0x002_001, width=12, output=0x001_002
-- ex. input=0x03_02_01, width=8, output=0x01_02_03
function wordrevorder (
arg : std_logic_vector;
width : positive
)
return std_logic_vector is
constant c_ratio : integer := arg'length/width;
variable v_ret : std_logic_vector(arg'range);
begin
for i in 0 to c_ratio-1 loop
v_ret((i*width)+width-1 downto (i*width)) :=
arg(((c_ratio-i-1)*width)+width-1 downto ((c_ratio-i-1)*width));
end loop;
return v_ret;
end;
begin
left <= wordrevorder(c, 1);
end architecture;
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