add link

README.md

@@ -6,6 +6,8 @@ The source code is copied from
 Stephen A. Edwards, sedwards@cs.columbia.edu
 http://www1.cs.columbia.edu/~sedwards
 
+http://www1.cs.columbia.edu/~sedwards/apple2fpga/
+
 
 
 Build ToDO
@@ -14,3 +16,11 @@ Build ToDO
 - Download the Apple II roms from the web
 - 
 
+
+
+
+F12 Switch debug info screen on/off
+F2  Track + 1
+F3  Track - 1
+
+F6  Switch b/w mode / colormode

src/Debouncer.vhd

@@ -1,45 +0,0 @@
--- (C) Rui T. Sousa from http://sweet.ua.pt/~a16360
-
-library IEEE;
-use IEEE.STD_LOGIC_1164.ALL;
-use IEEE.STD_LOGIC_ARITH.ALL;
-use IEEE.STD_LOGIC_UNSIGNED.ALL;
-
-entity Debouncer is
-	generic (Delay : positive);
-	port (
-		Clock  : in STD_LOGIC;
-		Reset  : in STD_LOGIC;
-		Input  : in STD_LOGIC;
-		Output : out STD_LOGIC
-	);
-end Debouncer;
-
-architecture Behavioral of Debouncer is
-
-	signal DelayCounter : natural range 0 to Delay;
-	signal Internal     : STD_LOGIC;
-
-begin
-
-	process(Clock, Reset)
-	begin
-		if rising_edge(Clock) then
-		if Reset = '1' then
-			Output <= '0';
-			Internal <= '0';
-			DelayCounter <= 0;
-		else
-			if Input /= Internal then
-				Internal <= Input;
-				DelayCounter <= 0;
-			elsif DelayCounter = Delay then
-				Output <= Internal;
-			else
-				DelayCounter <= DelayCounter + 1;
-			end if;
-		end if;
-		end if;
-	end process;
-
-end Behavioral;