Fixed controller lcd output by adding edge detection on lcd_busy. added testbench for controller.

controller.vhd

@@ -56,8 +56,12 @@ architecture Behavioral of controller is
 	signal lcd_newchar_reg,lcd_newchar_next : std_logic := '0';
 	signal lcd_data_reg, lcd_data_next: unsigned(7 downto 0) :=(others => '0');
 	
-	type character_array is array (15 downto 0) of character;
-	constant line1 : character_array := ( 'h', 'e', 'l','l','o', others=> ' ' );
+	type character_array is array (0 to 15) of character;
+	constant line1 : character_array := ( 'h', 'e', 'l','l','o',' ', 'A', 'a', 'r', 'o', 'n', others=> ' ' );
+	
+	-- for edge detection on lcd_busy
+	signal busy_old_reg, busy_old_next : std_logic := '0';
+
 
 begin
 
@@ -71,6 +75,7 @@ begin
 			charcnt_reg <= (others => '0');
 			lcd_newchar_reg <= '0';
 			lcd_data_reg <= (others => '0');
+			busy_old_reg <= '0';
 		
 		elsif(rising_edge(clk)) then
 			digpos_reg <= digpos_next;
@@ -80,6 +85,7 @@ begin
 			charcnt_reg <= charcnt_next;
 			lcd_newchar_reg<= lcd_newchar_next;
 			lcd_data_reg <= lcd_data_next;
+			busy_old_reg <= busy_old_next;
 			
 		end if;
 	end process proc1;
@@ -103,7 +109,7 @@ begin
 	lcd_data <= lcd_data_reg;
 	lcd_newchar <= lcd_newchar_reg;
 	
-	proc2: process(digit_reg,enc_updown,enc_ce,enc_err,enc_btn,digpos_reg,btn_old_reg, charcnt_reg, lcd_busy, lcd_data_reg, lcd_newchar_reg) 
+	proc2: process(digit_reg,enc_updown,enc_ce,enc_err,enc_btn,digpos_reg,btn_old_reg, charcnt_reg, lcd_busy, lcd_data_reg, lcd_newchar_reg, busy_old_reg) 
 	begin
 		digit_next <= digit_reg;
 		digpos_next <= digpos_reg;
@@ -112,6 +118,7 @@ begin
 		charcnt_next <= charcnt_reg;
 		lcd_newchar_next <= '0';
 		lcd_data_next <= lcd_data_reg;
+		busy_old_next <= lcd_busy;
 		
 		if(enc_ce='1' and enc_err='0') then
 			if(enc_updown='1') then
@@ -127,7 +134,7 @@ begin
 			end if;
 		end if;
 		
-		if(lcd_busy = '0' and charcnt_reg < 10) then
+		if(lcd_busy = '0' and busy_old_reg ='1' and charcnt_reg < 16) then
 				lcd_data_next <= to_unsigned(character'pos(line1(to_integer(charcnt_reg))),8);
 				lcd_newchar_next <= '1';
 				charcnt_next <= charcnt_reg + 1;

controller_tb.vhd

@@ -0,0 +1,118 @@
+--------------------------------------------------------------------------------
+-- Company: 
+-- Engineer:
+--
+-- Create Date:   20:08:51 06/06/2016
+-- Design Name:   
+-- Module Name:   /home/timo/workspace/vhdl-yasg/controller_tb.vhd
+-- Project Name:  yasg
+-- Target Device:  
+-- Tool versions:  
+-- Description:   
+-- 
+-- VHDL Test Bench Created by ISE for module: controller
+-- 
+-- Dependencies:
+-- 
+-- Revision:
+-- Revision 0.01 - File Created
+-- Additional Comments:
+--
+-- Notes: 
+-- This testbench has been automatically generated using types std_logic and
+-- std_logic_vector for the ports of the unit under test.  Xilinx recommends
+-- that these types always be used for the top-level I/O of a design in order
+-- to guarantee that the testbench will bind correctly to the post-implementation 
+-- simulation model.
+--------------------------------------------------------------------------------
+LIBRARY ieee;
+USE ieee.std_logic_1164.ALL;
+ 
+-- Uncomment the following library declaration if using
+-- arithmetic functions with Signed or Unsigned values
+USE ieee.numeric_std.ALL;
+ 
+ENTITY controller_tb IS
+END controller_tb;
+ 
+ARCHITECTURE behavior OF controller_tb IS 
+ 
+    -- Component Declaration for the Unit Under Test (UUT)
+ 
+    COMPONENT controller
+    PORT(
+         clk : IN  std_logic;
+         rst : IN  std_logic;
+         enc_updown : IN  std_logic;
+         enc_ce : IN  std_logic;
+         enc_btn : IN  std_logic;
+         enc_err : IN  std_logic;
+         lcd_busy : IN  std_logic;
+         lcd_data : OUT  unsigned(7 downto 0);
+         lcd_newchar : OUT  std_logic;
+         freq_out : OUT  unsigned(16 downto 0)
+        );
+    END COMPONENT;
+    
+
+   --Inputs
+   signal clk : std_logic := '0';
+   signal rst : std_logic := '0';
+   signal enc_updown : std_logic := '0';
+   signal enc_ce : std_logic := '0';
+   signal enc_btn : std_logic := '0';
+   signal enc_err : std_logic := '0';
+   signal lcd_busy : std_logic := '0';
+
+ 	--Outputs
+   signal lcd_data : unsigned(7 downto 0);
+   signal lcd_newchar : std_logic;
+   signal freq_out : unsigned(16 downto 0);
+
+   -- Clock period definitions
+   constant clk_period : time := 10 ns;
+ 
+BEGIN
+ 
+	-- Instantiate the Unit Under Test (UUT)
+   uut: controller PORT MAP (
+          clk => clk,
+          rst => rst,
+          enc_updown => enc_updown,
+          enc_ce => enc_ce,
+          enc_btn => enc_btn,
+          enc_err => enc_err,
+          lcd_busy => lcd_busy,
+          lcd_data => lcd_data,
+          lcd_newchar => lcd_newchar,
+          freq_out => freq_out
+        );
+
+   -- Clock process definitions
+   clk_process :process
+   begin
+		clk <= '0';
+		wait for clk_period/2;
+		clk <= '1';
+		wait for clk_period/2;
+   end process;
+ 
+
+   -- Stimulus process
+   stim_proc: process
+   begin		
+      -- hold reset state for 100 ns.
+      wait for 100 ns;	
+
+      wait for clk_period*10;
+		
+		rst<= '0';
+		lcd_busy <= '0';
+		
+
+      -- insert stimulus here 
+
+      wait;
+   end process;
+
+END;