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Altera_Forum
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15 years ago

Up/down counter Quartus II UP2 board

Hi guys!!!

i'm new in altera forum, and in vhdl too.

i must to do this project in Quartus II with the support of UP 2 board:

design an up/down decimal counter that:

1. show the count in a two 7 segment display in the UP2 board;

2. we can select the initial number of the count by switchs;

3. pushing the button present in UP2 board the counter must invert the count.

Someone can help me???

I Thanks you advance..:D

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Why don't you show us what you wrote until now so that we can give you some advice?

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Use counter from LPM library. It has most of the functionality you ask for. You need to code a HEX-to-7-segment active low decoder.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    before to show my vhdl code i thanks you for reply me :))))

    this is my work until now:

    library ieee;

    use ieee.std_logic_1164.all;

    use ieee.std_logic_unsigned.all;

    ENTITY counter IS

    PORT(

    clk : in BIT;

    upordwn : in STD_LOGIC;

    initial : in STD_LOGIC_VECTOR(7 DOWNTO 0);

    count : OUT STD_LOGIC_VECTOR(7 DOWNTO 0);

    LED_1 : OUT STD_LOGIC_VECTOR(7 DOWNTO 0);

    LED_2 : OUT STD_LOGIC_VECTOR(7 DOWNTO 0);

    LED_CENT : OUT STD_LOGIC_VECTOR(7 DOWNTO 0));

    end counter;

    ARCHITECTURE prova OF counter IS

    SIGNAL totalbit : STD_LOGIC_VECTOR(7 DOWNTO 0);

    SIGNAL up_four : STD_LOGIC_VECTOR(4 DOWNTO 0);

    SIGNAL low_four : STD_LOGIC_VECTOR(4 DOWNTO 0);

    BEGIN

    PROCESS(clk)

    --QUI DEVO INSERIRE IL VALORE INIZIALE

    if(clk'EVENT AND clk='1') THEN

    if (upordwn='1') THEN

    totalbit <= totalbit+1;

    else

    totalbit <= totalbit-1;

    end if;

    end if;

    END PROCESS;

    low_four(0) <= totalbit(0);

    low_four(1) <= totalbit(1);

    low_four(2) <= totalbit(2);

    low_four(3) <= totalbit(3);

    up_four(0) <= totalbit(4);

    up_four(1) <= totalbit(5);

    up_four(2) <= totalbit(6);

    up_four(3) <= totalbit(7);

    WITH up_four SELECT

    --abcdefg

    LED_1 <= "00000011" WHEN "1111", -- 0

    "10011111" WHEN "1110", -- 1

    "00100101" WHEN "1101", -- 2

    "00001101" WHEN "1100", -- 3

    "10011001" WHEN "1011", -- 4

    "01001001" WHEN "1010", -- 5

    "01000001" WHEN "1001", -- 6

    "00011111" WHEN "1000", -- 7

    "00000001" WHEN "0111", -- 8

    "00001001" WHEN "0110", -- 9

    "00010001" WHEN "0101", -- A

    "00000001" WHEN "0100", -- B

    "01100011" WHEN "0011", -- C

    "00000011" WHEN "0010", -- D

    "01100001" WHEN "0001", -- E

    "01110001" WHEN "0000", -- F

    "00000011" WHEN OTHERS;

    --Lower 4 bits

    WITH low_four SELECT

    --abcdefg

    LED_2 <= "00000011" WHEN "1111", -- 0

    "10011111" WHEN "1110", -- 1

    "00100101" WHEN "1101", -- 2

    "00001101" WHEN "1100", -- 3

    "10011001" WHEN "1011", -- 4

    "01001001" WHEN "1010", -- 5

    "01000001" WHEN "1001", -- 6

    "00011111" WHEN "1000", -- 7

    "00000001" WHEN "0111", -- 8

    "00001001" WHEN "0110", -- 9

    "00010001" WHEN "0101", -- A

    "00000001" WHEN "0100", -- B

    "01100011" WHEN "0011", -- C

    "00000011" WHEN "0010", -- D

    "01100001" WHEN "0001", -- E

    "01110001" WHEN "0000", -- F

    "00000011" WHEN OTHERS;

    count <= totalbit;

    end prova;

    I have two problems yet!

    1. initialing a strart number for the count by 8 switches present in UP2 board;

    2. show the result in decimal (not in hexadecimal format) in the 7segment display.

    thanks again :D
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    You could include a reset signal input that would load the value from the initial input to the totalbits value.

    You can design your process this way: 

    PROCESS (clk,reset)
  IF (reset='1') THEN
    -- initialization of signals and outputs
  ELSIF (clk'EVENT AND clk='1') THEN
    -- counting
  END IF;
END PROCESS;

    To change from hexadecimal to decimal you can use the arithmetic library and divisions by 10.