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Altera_Forum
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9 years ago

Scrolling Text - 7 Segment Display on DE0-CV

I would like to make scrolling text with the six 7 segment displays on the DE0-CV. I am trying to implement this project using VHDL. I am unsure how to approach this because I am unsure how to create an array that would cover all the pins from the six 7 segment displays. I do see that HEX0 has 7 assignments in the assignment editor and they are assigned like this (by using the system builder from the DE0-CV_v.1.2.1_SystemCD).http://www.alteraforum.com/forum/attachment.php?attachmentid=13067&stc=1

Would it be possible to create one output that could handle all the pins from the six 7 segment displays? I will also attach the vhdl code I have so far (mostly guessing and checking). 

LIBRARY ieee;
USE ieee.std_logic_1164.all;
ENTITY hexscroll IS
PORT( 
CLOCK_50 : IN STD_LOGIC;
HEX0 		: OUT STD_LOGIC_VECTOR(6 downto 0);
HEX1 		: OUT STD_LOGIC_VECTOR(6 downto 0);
HEX2 		: OUT STD_LOGIC_VECTOR(6 downto 0);
HEX3 		: OUT STD_LOGIC_VECTOR(6 downto 0);
HEX4 		: OUT STD_LOGIC_VECTOR(6 downto 0);
HEX5 		: OUT STD_LOGIC_VECTOR(6 downto 0));
END hexscroll;
	
ARCHITECTURE blinkled OF hexscroll IS
	SIGNAL pulse : STD_LOGIC_VECTOR (6 downto 0) := B"010_0100";--variable to hold value of LED
	SIGNAL count : INTEGER RANGE 0 TO 49999999 := 0; --counter variable
	TYPE HEX IS ARRAY (41 downto 0) OF STD_LOGIC;
BEGIN
	counter:PROCESS (CLOCK_50)
	BEGIN
		IF CLOCK_50'EVENT AND CLOCK_50 = '1' THEN
			
			IF count = 49999999 THEN
				count <= 0;
				pulse <= NOT pulse;
			ELSE
				count <= count + 1;
			END IF;
		END IF;
	END PROCESS counter;
	
	HEX0(6 downto 0) <= pulse;--B"111_1001";
	--HEX0(6 downto 0) <= (others => pulse);
			--HEX0(6 downto 0) <= B"111_1001";
			--HEX1(6 downto 0) <= B"000_1000";
			--HEX2(6 downto 0) <= B"000_1100";
			--HEX3(6 downto 0) <= B"100_1000";
			--HEX4(6 downto 0) <= B"000_0110";				
			--HEX5(6 downto 0) <= B"001_0010";
END blinkled;

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    Dont create an array of std_logic, you're just redifining the std_logic_vector type. Just create an array of std_logic_vector in a package, then import it into your entity: 

    
package my_types_pkg is
  type hexout_array_t is array(0 to 5) of std_logic_vector(6 downto 0);
end package;
....
use work.my_types_pkg.all;
entity hexscroll is
  port (
    hexout  : hexout_array_t
  );
end entity hexscroll;
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    Alright, before I waste my time guessing on what to do, would I assign all the pins to hexout or would I instead somehow fill the array (hexout) with HEX0 to HEX5 (which already have the pins assigned to them)? Here is the code I have come up with so far. I tried to assign the HEX0-HEX5 to the hexout, but error showed up saying I had to change them to a buffer type. 

    LIBRARY ieee;USE ieee.std_logic_1164.all;
USE work.my_types_pkg.all;
ENTITY hexscroll IS
PORT(
CLOCK_50 : IN STD_LOGIC;
hexout   : OUT hexout_array_t;
HEX0 		: BUFFER STD_LOGIC_VECTOR(6 downto 0);
HEX1 		: BUFFER STD_LOGIC_VECTOR(6 downto 0);
HEX2 		: BUFFER STD_LOGIC_VECTOR(6 downto 0);
HEX3 		: BUFFER STD_LOGIC_VECTOR(6 downto 0);
HEX4 		: BUFFER STD_LOGIC_VECTOR(6 downto 0);
HEX5 		: BUFFER STD_LOGIC_VECTOR(6 downto 0));
END hexscroll;
	
ARCHITECTURE blinkled OF hexscroll IS
	SIGNAL pulse : STD_LOGIC_VECTOR (6 downto 0) := B"010_0100";--variable to hold value of LED
	SIGNAL count : INTEGER RANGE 0 TO 49999999 := 0; --counter variable
	
BEGIN
	counter:PROCESS (CLOCK_50)
	BEGIN
		hexout <= (HEX0, HEX1, HEX2, HEX3, HEX4, HEX5);
		IF CLOCK_50'EVENT AND CLOCK_50 = '1' THEN
			
			IF count = 49999999 THEN
				count <= 0;
				pulse <= NOT pulse;
			ELSE
				count <= count + 1;
			END IF;
		END IF;
	END PROCESS counter;
	--hexout <= ???
END blinkled;

    LIBRARY IEEE;USE ieee.std_logic_1164.all;
PACKAGE my_types_pkg IS
  
  TYPE hexout_array_t IS ARRAY(0 to 5) OF STD_LOGIC_VECTOR(6 downto 0);
END PACKAGE;