I have designed 4-digit BCD Counter and BCD-to-7segment Converter as a project of one of my courses in the university.
Here is the circuit: http://img849.imageshack.us/img849/930/111vr.png
and here is the source code:
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity IC_74163 is
port(LdN, ClrN, P, T, ClK: in std_logic;
D: in std_logic_vector(3 downto 0);
Cout: out std_logic; Qout: out std_logic_vector(3 downto 0) );
end entity;
architecture IC_74163_1 of IC_74163 is
signal Q: std_logic_vector(3 downto 0); -- Q is the counter register
begin
Qout <= Q;
Cout <= Q(3) and Q(2) and Q(1) and Q(0) and T;
process (CLK)
begin
if CLK'event and CLK = '1' then -- change state on rising edge
if ClrN = '0' then Q <= "0000";
elsif LdN = '0' then Q <= D;
elsif (P and T) = '1' then Q <= Q+1;
end if;
end if;
end process;
end architecture;
==============================
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity Four_Digit_BCD_Counter is
port(Clk: in std_logic;
Q1, Q2, Q3, Q4: inout std_logic_vector(3 downto 0):= "0000");
end entity;
architecture Four_Digit_BCD_Counter_1 of Four_Digit_BCD_Counter is
component IC_74163 is
port(LdN, ClrN, P, T, ClK: in std_logic;
D: in std_logic_vector(3 downto 0);
Cout: out std_logic; Qout: out std_logic_vector(3 downto 0) );
end component;
signal ClrN1, ClrN2, ClrN3, ClrN4: std_logic;
signal T2, T3, T4: std_logic;
begin
ClrN1 <= Q1(3) NOR Q1(0);
ClrN2 <= Q2(3) NOR Q2(0);
ClrN3 <= Q3(3) NOR Q3(0);
ClrN4 <= Q4(3) NOR Q4(0);
T2 <= not (Q1(3) NOR Q1(0));
T3 <= not (Q2(3) NOR Q2(0));
T4 <= not (Q3(3) NOR Q3(0));
IC_1: IC_74163 port map ('1',ClrN1,'1','1',Clk,"ZZZZ",open,Q1);
IC_2: IC_74163 port map ('1',ClrN2,'1',T2,Clk,"ZZZZ",open,Q2);
IC_3: IC_74163 port map ('1',ClrN3,'1',T3,Clk,"ZZZZ",open,Q3);
IC_4: IC_74163 port map ('1',ClrN4,'1',T4,Clk,"ZZZZ",open,Q4);
end architecture;
==============================
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity BCD_to_Seven_Segment_Converter is
port(B3, B2, B1, B0 :in std_logic; output:out integer range 0 to 9);
end entity;
architecture BCD_to_Seven_Segment_Converter_1 of BCD_to_Seven_Segment_Converter is
signal ss:std_logic_vector(6 downto 0);
signal a, b, c, d, e, f, g:std_logic;
begin
a <= B3 or ((not B0) and (not B2)) or B1 or (B0 and B2);
b <= (not B2) or ((not B0) and (not B1)) or (B0 and B1);
c <= (not B1) or B0 or B2;
d <= B3 or ((not B0) and (not B2)) or ((not B0) and B1) or (B0 and (not B1) and B2) or (B1 and (not B2));
e <= ((not B0) and B1) or ((not B0) and (not B2));
f <= B3 or ((not B0) and B2) or ((not B0) and (not B1)) or ((not B1) and B2);
g <= B3 or ((not B1) and B2) or (B1 and (not B2)) or ((not B0) and B1);
process(ss)
begin
case ss is
when "1111110" => output <= 0;
when "0110000" => output <= 1;
when "1101101" => output <= 2;
when "1111001" => output <= 3;
when "0110011" => output <= 4;
when "1011011" => output <= 5;
when "1011111" => output <= 6;
when "1110000" => output <= 7;
when "1111111" => output <= 8;
when "1111011" => output <= 9;
when others => null;
end case;
end process;
--process(input)
--begin
--case input is
--when "0000" => output <= "1111110";
--when "0001" => output <= "0110000";
--when "0010" => output <= "1101101";
--when "0011" => output <= "1111001";
--when "0100" => output <= "0110011";
--when "0101" => output <= "1011011";
--when "0110" => output <= "1011111";
--when "0111" => output <= "1110000";
--when "1000" => output <= "1111111";
--when "1001" => output <= "1111011";
--when others => null;
--end case;
--end process;
end architecture;
==============================
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity Project is
port(Clk: in std_logic; Count: out integer range 0000 to 9999 := 0000);
end entity;
architecture The_Circiut of Project is
component Four_Digit_BCD_Counter is
port(Clk: in std_logic;
Q1, Q2, Q3, Q4: inout std_logic_vector(3 downto 0):= "0000");
end component;
component BCD_to_Seven_Segment_Converter is
port(B3, B2, B1, B0 :in std_logic; output:out integer range 0 to 9);
end component;
signal Qout1, Qout2, Qout3, Qout4: std_logic_vector(3 downto 0):= "0000";
signal D0, D1, D2, D3:integer range 0 to 9;
begin
BCD_Counter_4Digit: Four_Digit_BCD_Counter port map (Clk, Qout1, Qout2, Qout3, Qout4);
BCD_7Segment_Converter1: BCD_to_Seven_Segment_Converter port map (Qout1(0), Qout1(1), Qout1(2), Qout1(3), D0);
BCD_7Segment_Converter2: BCD_to_Seven_Segment_Converter port map (Qout2(0), Qout2(1), Qout2(2), Qout2(3), D1);
BCD_7Segment_Converter3: BCD_to_Seven_Segment_Converter port map (Qout3(0), Qout3(1), Qout3(2), Qout3(3), D2);
BCD_7Segment_Converter4: BCD_to_Seven_Segment_Converter port map (Qout4(0), Qout4(1), Qout4(2), Qout4(3), D3);
Count <= D3 * 1000 + D2 * 100 + D1 * 10 + D0;
end architecture;
The problem is that, Count
stays 0
forever and does not change and count up. Could you help me to figure out the problem?
====================================
EDIT:
Well, after I edited the problems that @MRAB and @Tomi Junnila mentioned the problem does not fixed!
Also, I have tried to test IC_74163
alone, and I think it is the source of the problem, it gives me Qout
as X
!! Can you guys test it for me please? I am using Active-HDL btw.
====================================
EDIT2:
Here is the waveform for IC_74163
: http://img851.imageshack.us/img851/8117/52226324.png
====================================
EDIT3:
OK, the counter is working very well but I still have very small issue. I have four std_logic_vector(3 downto 0)
which are Qout1
, Qout2
, Qout3
and Qout4
.. How can I convert them to an integer of 4 digits ? std_logic_vector(3 downto 0):= "0000"
does not work well.
====================================
EDIT4:
OK guys, the counter is working as required and there is no issue. Thank you for your help, I really appreciate it.
Here is the final source code for anyone interested:
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity IC_74163 is
port(LdN, ClrN, P, T, ClK: in std_logic:='0';
D: in std_logic_vector(3 downto 0):="0000";
Cout: out std_logic; Qout: inout std_logic_vector(3 downto 0):="0000");
end entity;
architecture IC_74163_1 of IC_74163 is
begin
Cout <= Qout(3) and Qout(2) and Qout(1) and Qout(0) and T;
process (CLK)
begin
if CLK'event and CLK = '1' then -- change state on rising edge
if ClrN = '0' then Qout <= "0000";
elsif LdN = '0' then Qout <= D;
elsif (P and T) = '1' then Qout <= Qout+1;
end if;
end if;
end process;
end architecture;
==============================
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity Four_Digit_BCD_Counter is
port(Clk: in std_logic;
Q1, Q2, Q3, Q4: inout std_logic_vector(3 downto 0):= "0000");
end entity;
architecture Four_Digit_BCD_Counter_1 of Four_Digit_BCD_Counter is
component IC_74163 is
port(LdN, ClrN, P, T, ClK: in std_logic;
D: in std_logic_vector(3 downto 0);
Cout: out std_logic; Qout: inout std_logic_vector(3 downto 0) );
end component;
signal ClrN1, ClrN2, ClrN3, ClrN4: std_logic;
signal T2, T3, T4: std_logic;
begin
ClrN1 <= Q1(3) NAND Q1(0);
ClrN2 <= Q2(3) NAND Q2(0);
ClrN3 <= Q3(3) NAND Q3(0);
ClrN4 <= Q4(3) NAND Q4(0);
T2 <= not (Q1(3) NAND Q1(0));
T3 <= not (Q2(3) NAND Q2(0));
T4 <= not (Q3(3) NAND Q3(0));
IC_1: IC_74163 port map ('1',ClrN1,'1','1',Clk,"ZZZZ",open,Q1);
IC_2: IC_74163 port map ('1',ClrN2,'1',T2,Clk,"ZZZZ",open,Q2);
IC_3: IC_74163 port map ('1',ClrN3,'1',T3,Clk,"ZZZZ",open,Q3);
IC_4: IC_74163 port map ('1',ClrN4,'1',T4,Clk,"ZZZZ",open,Q4);
end architecture;
==============================
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity BCD_to_Seven_Segment_Converter is
port(B3, B2, B1, B0 :in std_logic; output:out integer range 0 to 9);
end entity;
architecture BCD_to_Seven_Segment_Converter_1 of BCD_to_Seven_Segment_Converter is
signal ss:std_logic_vector(6 downto 0);
signal a, b, c, d, e, f, g:std_logic;
begin
a <= B3 or ((not B0) and (not B2)) or B1 or (B0 and B2);
b <= (not B2) or ((not B0) and (not B1)) or (B0 and B1);
c <= (not B1) or B0 or B2;
d <= B3 or ((not B0) and (not B2)) or ((not B0) and B1) or (B0 and (not B1) and B2) or (B1 and (not B2));
e <= ((not B0) and B1) or ((not B0) and (not B2));
f <= B3 or ((not B0) and B2) or ((not B0) and (not B1)) or ((not B1) and B2);
g <= B3 or ((not B1) and B2) or (B1 and (not B2)) or ((not B0) and B1);
ss <= a&b&c&d&e&f&g;
process(ss)
begin
case ss is
when "1111110" => output <= 0;
when "0110000" => output <= 1;
when "1101101" => output <= 2;
when "1111001" => output <= 3;
when "0110011" => output <= 4;
when "1011011" => output <= 5;
when "1011111" => output <= 6;
when "1110000" => output <= 7;
when "1111111" => output <= 8;
when "1111011" => output <= 9;
when others => null;
end case;
end process;
--process(input)
--begin
--case input is
--when "0000" => output <= "1111110";
--when "0001" => output <= "0110000";
--when "0010" => output <= "1101101";
--when "0011" => output <= "1111001";
--when "0100" => output <= "0110011";
--when "0101" => output <= "1011011";
--when "0110" => output <= "1011111";
--when "0111" => output <= "1110000";
--when "1000" => output <= "1111111";
--when "1001" => output <= "1111011";
--when others => null;
--end case;
--end process;
end architecture;
==============================
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity Project is
port(Clk: in std_logic; Count: out integer range 0000 to 9999 := 0000);
end entity;
architecture The_Circiut of Project is
component Four_Digit_BCD_Counter is
port(Clk: in std_logic;
Q1, Q2, Q3, Q4: inout std_logic_vector(3 downto 0):= "0000");
end component;
component BCD_to_Seven_Segment_Converter is
port(B3, B2, B1, B0 :in std_logic; output:out integer range 0 to 9);
end component;
signal Qout1, Qout2, Qout3, Qout4: std_logic_vector(3 downto 0):= "0000";
signal D0, D1, D2, D3:integer range 0 to 9;
begin
BCD_Counter_4Digit: Four_Digit_BCD_Counter port map (Clk, Qout1, Qout2, Qout3, Qout4);
BCD_7Segment_Converter1: BCD_to_Seven_Segment_Converter port map (Qout1(3), Qout1(2), Qout1(1), Qout1(0), D0);
BCD_7Segment_Converter2: BCD_to_Seven_Segment_Converter port map (Qout2(3), Qout2(2), Qout2(1), Qout2(0), D1);
BCD_7Segment_Converter3: BCD_to_Seven_Segment_Converter port map (Qout3(3), Qout3(2), Qout3(1), Qout3(0), D2);
BCD_7Segment_Converter4: BCD_to_Seven_Segment_Converter port map (Qout4(3), Qout4(2), Qout4(1), Qout4(0), D3);
Count <= D3 * 1000 + D2 * 100 + D1 * 10 + D0;
end architecture;
You don't assign anything to the ss
signal in the BCD_to_Seven_Segment_Converter_1
architecture, yet that signal is used to determine the output
signal. If I had to hazard a guess, you actually want to look at the signals a
through g
.
There is also a far easier way to convert the 4 bits to an integer:
--...
signal v : std_logic_vector(3 downto 0);
begin
v <= B3 & B2 & B1 & B0;
CONV: process(v)
case v is
when "0000" => output <= 0;
when "0001" => output <= 1;
when "0010" => output <= 2;
-- etc, don't forget "when others"
end case;
end process CONV;
--...
You are probably also not resetting the IC_74163
properly. It uses a synchronous reset, so it will only reset on a rising clock edge when ClrN
is '0'. However, ClrN
is driven by combo logic based on the output, so it will never get set to '0', since Qout
s initialize to "UUUU".