DISEÑO LÓGICO (DLO) Ejemplos de VHDL

Biestable D - latch library IEEE; use IEEE.std_logic_1164.all; entity DLatch is port ( GATE: in STD_LOGIC; DIN: in STD_LOGIC; DOUT: out STD_LOGIC ); end DLatch; architecture DLatch_arch of DLatch is begin process (GATE, DIN) if GATE='1' then -- habilitación del biestable activa a nivel alto DOUT <= DIN; end if; end process; end DLatch_arch;

Biestable D-latch con reset library IEEE; use IEEE.std_logic_1164.all; entity DLatchR is port ( GATE: in STD_LOGIC; RESET: in STD_LOGIC; DIN: in STD_LOGIC; DOUT: out STD_LOGIC ); end DLatchR; architecture DLatchR_arch of DLatchR is begin process (GATE, DIN, RESET) if RESET='1' then -- RESET activo a nivel alto DOUT <= '0'; elsif GATE='1' then -- habilitación del biestable activa a nivel alto DOUT <= DIN; end if; end process; end DLatchR_arch;

Biestable D- flip-flop, (sin y con reset) library IEEE; use IEEE.std_logic_1164.all; entity DFlipFlop is port ( CLK: in STD_LOGIC; DIN: in STD_LOGIC; DOUT: out STD_LOGIC ); end DFlipFlop; architecture DFlipFlop_arch of DFlipFlop is begin process (CLK) if CLK'event and CLK='1' then -- CLK rising edge DOUT <= DIN; end if; end process; end DFlipFlop_arch; library IEEE; use IEEE.std_logic_1164.all; entity DFlipFlopR is port ( CLK: in STD_LOGIC; RESET: in STD_LOGIC; DIN: in STD_LOGIC; DOUT: out STD_LOGIC ); end DFlipFlopR; architecture DFlipFlopR_arch of DFlipFlopR is begin process (CLK, RESET) if RESET='1' then -– RESET asíncrono activo alto DOUT <= '0'; elsif (CLK'event and CLK='1') then -- CLK rising edge DOUT <= DIN; end if; end process; end DFlipFlopR_arch; D con reset

Biestable D- flip-flop (Con CE, y reset síncronos library IEEE; use IEEE.std_logic_1164.all; entity DFlipFlopCE is port ( CLK: in STD_LOGIC; ENABLE: in STD_LOGIC; DIN: in STD_LOGIC; DOUT: out STD_LOGIC ); end DFlipFlopCE; architecture DFlipFlopCE_arch of DFlipFlopCE is begin process (CLK) if (CLK'event and CLK='1') then if (ENABLE='1') then DOUT <= DIN; end if; end process; end DFlipFlopCE_arch; library IEEE; use IEEE.std_logic_1164.all; entity DFlipFlopSR is port ( CLK: in STD_LOGIC; RESET: in STD_LOGIC; DIN: in STD_LOGIC; DOUT: out STD_LOGIC ); end DFlipFlopSR; architecture DFlipFlopSR_arch of DFlipFlopSR is begin process (CLK) if CLK'event and CLK='1' then --CLK rising edge if RESET='1' then --synchronous RESET active High DOUT <= '0'; else DOUT <= DIN; end if; end process; end DFlipFlopSR_arch; D con CE D con reset síncrono

Decodificador 3 a 8 library IEEE; use IEEE.std_logic_1164.all; entity deco3a8 is port ( RESET: in STD_LOGIC; CLK: in STD_LOGIC; D_IN: in STD_LOGIC_VECTOR(2 downto 0); D_OUT: out STD_LOGIC_VECTOR(7 downto 0) ); end deco3a8 ; architecture deco3a8_arch of deco3a8 is begin process(CLK, RESET, D_IN) if ( RESET = '1') then D_OUT <= "00000000"; elsif ( CLK'event and CLK ='1') then case D_IN is when "000" => D_OUT <= "00000001"; when "001" => D_OUT <= "00000010"; when "010" => D_OUT <= "00000100"; when "011" => D_OUT <= "00001000"; when "100" => D_OUT <= "00010000"; when "101" => D_OUT <= "00100000"; when "110" => D_OUT <= "01000000"; when "111" => D_OUT <= "10000000"; when others => NULL; end case; end if; end process; end deco3a8_arch;

Codificador 8 a 3 library IEEE; use IEEE.std_logic_1164.all; entity enco8a3 is port ( RESET: in STD_LOGIC; CLK: in STD_LOGIC; D_IN: in STD_LOGIC_VECTOR(7 downto 0); D_OUT: out STD_LOGIC_VECTOR(2 downto 0) ); end enco8a3 ; architecture enco8a3_arch of enco8a3 is begin process(CLK,RESET,D_IN) if ( RESET = '1') then D_OUT <= "000"; elsif ( CLK'event and CLK ='1') then case D_IN is when "00000001" => D_OUT <= "000"; when "00000010" => D_OUT <= "001"; when "00000100" => D_OUT <= "010"; when "00001000" => D_OUT <= "011"; when "00010000" => D_OUT <= "100"; when "00100000" => D_OUT <= "101"; when "01000000" => D_OUT <= "110"; when "10000000" => D_OUT <= "111"; when others => NULL; end case; end if; end process; end enco8a3_arch;

Multiplexor 4 a 1 library IEEE; use IEEE.std_logic_1164.all; entity Mux4a1 is port ( SEL: in STD_LOGIC_VECTOR(1 downto 0); A, B, C, D:in STD_LOGIC; MUX_OUT: out STD_LOGIC ); end Mux4a1; architecture Mux4a1_arch of Mux4a1 is begin process (SEL, A, B, C, D) case SEL is when "00" => MUX_OUT <= A; when "01" => MUX_OUT <= B; when "10" => MUX_OUT <= C; when "11" => MUX_OUT <= D; when others => MUX_OUT <= 'X'; end case; end process; end Mux4a1_arch;

Contador de 4 bits library IEEE; use IEEE.std_logic_1164.all; entity Contador is port ( CLK: in STD_LOGIC; RESET: in STD_LOGIC; CE, LOAD, DIR: in STD_LOGIC; DIN: in INTEGER range 0 to 15; COUNT: inout INTEGER range 0 to 15 ); end Contador; architecture Contador_arch of Contador is begin process (CLK, RESET) if RESET='1' then COUNT <= 0; elsif CLK='1' and CLK'event then if LOAD='1' then COUNT <= DIN; else if CE='1' then if DIR='1' then COUNT <= COUNT + 1; COUNT <= COUNT - 1; end if; end process; end Contador_arch;