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-- This logic is implemented in up_counter.vhdl example as well, but there tmp variable is declared as unsigned
--whereas here it is declared as std_logic_vector; which requires type conversion.
--slv stands for std_logic_vector
library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
entity up_counter_slv is
port(C : in std_logic;
CLR : in std_logic;
Q : out std_logic_vector(3 downto 0));
end up_counter_slv;
architecture bhv of up_counter_slv is
signal tmp: std_logic_vector(3 downto 0);
begin
process (C, CLR)
begin
if (CLR='1') then
tmp <= "0000";
elsif (C'event and C='1') then
tmp <= std_logic_vector(to_unsigned(1+to_integer(unsigned(tmp)), tmp'length));
end if;
end process;
Q <= tmp;
end bhv;
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