I tried to compile the code presented some days ago in this newsgroup. I use Altera QuartusII v3.0 SP2
and got the following warning:
Warning: VHDL Subtype or Type Declaration warning at numeric_std.vhd(878): subtype or type has null range Switching left and right bound of range.
Was does that mean?
Apart from that I get the Info "No valid register-to-register paths exist for clock Clk"
What does go wrong with timing calculation?
library ieee; use ieee.std_logic_1164.all; use ieee.numeric_std.all;
entity barrelshifter is port( Quantity : in unsigned(31 downto 0); Amount : in unsigned(4 downto 0); Reset : in std_logic; Clk : in std_logic; Output : out std_logic_vector(31 downto 0) ); end barrelshifter;
architecture ro_lft of barrelshifter is signal rotated : std_logic_vector(31 downto 0); signal rotate_by : unsigned(4 downto 0);