Code VHDL - expand12345678process (clk ) begin if clk 'event and clk =' 1' then if (Load = ' 1' ) thenq. Code VHDL - expand1234Dff1: entity work. Dff port map (d = Dsig ( 1 ), preset = ' 0', clear = ' 0', clk = Clksig, q = Qsig ( 1 ) );Dff2: entity work. Just cause 2 free download full version pc. Dff port map (d = Dsig ( 2 ), preset = ' 0', clear = ' 0', clk = Clksig, q = Qsig ( 2 ) );Dff3: entity work. Dff port map (d = Dsig ( 3 ), preset = ' 0', clear = ' 0', clk = Clksig, q = Qsig ( 3 ) );Dff4: entity work. Dff port map (d = Dsig ( 4 ), preset = ' 0', clear = ' 0', clk = Clksig, q = Qsig ( 4 ) );Now think about the logic for the four 'D' inputs to the flip flops (i.e. The 'Dsig' signals).

The clock inputs of all the flip-flops are connected together and are triggered by the input pulses. Thus, all the flip-flops change state. Nov 05, 2015  You are required to design a 4-bit even up-counter using D flip flop by converting combinational circuit to sequential circuit. The counter will only consider even inputs and the sequence of inputs will be 0-2-4-6-8-10-0.

If load is true, you want to load in the new input values from the entity (assuming them to be 'D(1 to 4)'; if it is false then you don't want Qsig to change. Consider the following and see if you think it does the trick. Code VHDL - expand12345678process (clk ) begin if clk 'event and clk =' 1' then if (Load = ' 1' ) thenq. Code VHDL - expand1234Dff1: entity work. Dff port map (d = Dsig ( 1 ), preset = ' 0', clear = ' 0', clk = Clksig, q = Qsig ( 1 ) );Dff2: entity work.

Dff port map (d = Dsig ( 2 ), preset = ' 0', clear = ' 0', clk = Clksig, q = Qsig ( 2 ) );Dff3: entity work. Dff port map (d = Dsig ( 3 ), preset = ' 0', clear = ' 0', clk = Clksig, q = Qsig ( 3 ) );Dff4: entity work. Dff port map (d = Dsig ( 4 ), preset = ' 0', clear = ' 0', clk = Clksig, q = Qsig ( 4 ) );Now think about the logic for the four 'D' inputs to the flip flops (i.e. The 'Dsig' signals). If load is true, you want to load in the new input values from the entity (assuming them to be 'D(1 to 4)'; if it is false then you don't want Qsig to change. Consider the following and see if you think it does the trick. Code VHDL - expand1Dsig1.

Code VHDL - expand526272829library IEEE; use IEEE. All; use work.

Dff; entity bitreg4 is port (Clksig: in stdlogic;Load: in stdlogic; -D: in stdlogicvector(1 to 4);Dsig: in stdlogicvector ( 1 to 4 );Qsig: out stdlogicvector ( 1 to 4 ) ); end bitreg4; architecture bhv of bitreg4 is beginDff1: entity work. Dff port map (d = Dsig ( 1 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 1 ) );Dff2: entity work. Dff port map (d = Dsig ( 2 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 2 ) );Dff3: entity work. Dff port map (d = Dsig ( 3 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 3 ) );Dff4: entity work. Dff port map (d = Dsig ( 4 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 4 ) ); process (Clksig,Dsig,Load ) begin if Load = ' 1' thenQsig. In the port mapping, you set 'clear' to 0, according to the D FF I've posted, if clear is '0', then the output 'q' is always '0'.Then either- 'clear' is not named very well. Usually if a signal is active low (i.e.

Hilti profis installation download. A low logic level '0' means 'true') then you indicate as such in the name so that people (like me) looking quickly don't have to dig into the code to see what it does. The usual convention is for such a signal to have an 'n' suffix. One should be able to discern the function of a signal based on the port name in the entity. You shouldn't have to look at the architecture. Suppliers of parts will typically put an overbar in the name, but you can't do that in simple text file.- Maybe 'clear' is not implemented as intended in dff.

Perhaps the 'q' outputs should be cleared when 'clear = 1', not when it is 0. Code VHDL - expand526272829library IEEE; use IEEE. All; use work. Dff; entity bitreg4 is port (Clksig: in stdlogic;Load: in stdlogic; -D: in stdlogicvector(1 to 4);Dsig: in stdlogicvector ( 1 to 4 );Qsig: out stdlogicvector ( 1 to 4 ) ); end bitreg4; architecture bhv of bitreg4 is beginDff1: entity work. Dff port map (d = Dsig ( 1 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 1 ) );Dff2: entity work.

Dff port map (d = Dsig ( 2 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 2 ) );Dff3: entity work. Dff port map (d = Dsig ( 3 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 3 ) );Dff4: entity work. Dff port map (d = Dsig ( 4 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 4 ) ); process (Clksig,Dsig,Load ) begin if Load = ' 1' thenQsig.

Code VHDL - expand1Dsig. Code: library IEEE;use IEEE.stdlogic1164.all;entity dff isport (d: in stdlogic;preset: in stdlogic;clear: in stdlogic;clk: in stdlogic;q: out stdlogic);end dff;architecture bhvdff of dff isbeginprocess(clk, clear, preset)beginif clear = '0' thenq. Code VHDL - expand031library IEEE; use IEEE. All; entity dff is port (CLK: in stdlogic;CLEARF: in stdlogic;PRESET: in stdlogic;D: in stdlogic ( 3 downto 0 ); - 4-bit DFFQ: out stdlogic ( 3 downto 0 ) - 4-bit DFF ); end dff; architecture behav of dff is begin process (CLK, CLEARF, PRESET ) begin if CLEARF = ' 0' then - asynchronous CLEARFQ. Code VHDL - expand02122library IEEE; use IEEE. All; use work.

Dff; entity bitreg4 is port (Clksig: in stdulogic;Load: in stdulogic;D: in stdulogicvector ( 1 to 4 );Dsig: buffer stdulogicvector ( 1 to 4 );Qsig: buffer stdulogicvector ( 1 to 4 ) ); end bitreg4; architecture bhv of bitreg4 is beginDff1: entity work. Dff port map (d = Dsig ( 1 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 1 ) );Dff2: entity work. Dff port map (d = Dsig ( 2 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 2 ) );Dff3: entity work. Dff port map (d = Dsig ( 3 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 3 ) );Dff4: entity work. Dff port map (d = Dsig ( 4 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 4 ) );Dsig. Code VHDL - expand031library IEEE; use IEEE. All; entity bitreg42 is port (CLK: in stdlogic;CLEARF: in stdlogic;PRESET: in stdlogic;D: in stdlogicvector ( 3 downto 0 ); - 4-bit DFFQ: out stdlogicvector ( 3 downto 0 ); - 4-bit DFFLoad: in stdlogic ); end bitreg42; architecture behav of bitreg42 is begin process (CLK, CLEARF, PRESET ) begin if CLEARF = ' 0' then - asynchronous CLEARFQ.

Code VHDL - expand02122library IEEE; use IEEE. All; use work.

Dff; entity bitreg4 is port (Clksig: in stdulogic;Load: in stdulogic;D: in stdulogicvector ( 1 to 4 );Dsig: buffer stdulogicvector ( 1 to 4 );Qsig: buffer stdulogicvector ( 1 to 4 ) ); end bitreg4; architecture bhv of bitreg4 is beginDff1: entity work. Dff port map (d = Dsig ( 1 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 1 ) );Dff2: entity work.

Dff port map (d = Dsig ( 2 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 2 ) );Dff3: entity work. Dff port map (d = Dsig ( 3 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 3 ) );Dff4: entity work. Dff port map (d = Dsig ( 4 ), preset = ' 0', clear = ' 1', clk = Clksig,q = Qsig ( 4 ) );Dsig.

Code VHDL - expand031library IEEE; use IEEE. All; entity bitreg42 is port (CLK: in stdlogic;CLEARF: in stdlogic;PRESET: in stdlogic;D: in stdlogicvector ( 3 downto 0 ); - 4-bit DFFQ: out stdlogicvector ( 3 downto 0 ); - 4-bit DFFLoad: in stdlogic ); end bitreg42; architecture behav of bitreg42 is begin process (CLK, CLEARF, PRESET ) begin if CLEARF = ' 0' then - asynchronous CLEARFQ.