added basic design directory structure

1 files changed, 101 insertions, 0 deletions

diff --git a/src/play_rtl.vhd b/src/play_rtl.vhd
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+------------------------------------------------------------------
+-- module     : play
+------------------------------------------------------------------
+-- author     : Friedrich Beckmann
+-- company    : university of applied sciences augsburg
+------------------------------------------------------------------
+-- description: Statemachine for LED game
+--              
+------------------------------------------------------------------
+-- revisions : 0.1 - 
+------------------------------------------------------------------
+
+-- 5 LED outputs
+-- One one-second enable input
+-- KEY input with preceding rising_edge detector
+
+-- step LED4 LED3 LED2 LED1 LED0
+--  1    x    -    -    -    -
+--  2    -    x    -    -    -
+--  3    -    -    x    -    -
+--  4    -    -    -    x    -
+--  5    -    -    -    -    x
+--  6    x    -    -    -    -
+--  ...  this pattern continues
+-- If LED2 is on and KEY is pressed then the pattern continues as follows
+--  1    x    -    -    -    -
+--  2    -    -    -    -    x
+--  ... this pattern continues until
+--  KEY is pressed again. Then the previous pattern restarts from LED 2
+
+library ieee;
+use ieee.std_logic_1164.all;
+
+entity play is
+  port (clk        : in  std_ulogic;
+        rst_n      : in  std_ulogic;
+        onesec_i   : in  std_ulogic;
+        key_i      : in  std_ulogic;
+        led_o      : out std_ulogic_vector(4 downto 0));
+end play;
+
+architecture rtl of play is
+
+  type state_t is (start_s,one_s,chance_s,four_s,last_s,hit0_s,hit1_s);
+  signal current_state,next_state : state_t;
+
+begin
+
+  current_state <= start_s when rst_n = '0' else next_state when rising_edge(clk);
+
+  next_p : process(current_state, onesec_i, key_i)
+    begin
+      next_state <= current_state;
+      led_o <= "00000";
+      case current_state is
+        when start_s =>
+          led_o <= "10000";
+          if onesec_i = '1' then
+            next_state <= one_s;            
+          end if;
+        when one_s =>
+          led_o <= "01000";
+          if onesec_i = '1' then 
+            next_state <= chance_s;
+          end if;
+        when chance_s =>
+          led_o <= "00100";
+          if key_i = '1' then
+            next_state <= hit0_s;
+          elsif onesec_i = '1' then
+            next_state <= four_s; 
+          end if;
+        when four_s =>
+          led_o <= "00010";
+          if onesec_i = '1' then
+            next_state <= last_s;
+          end if;
+        when last_s =>
+          led_o <= "00001";
+          if onesec_i = '1' then
+            next_state <= start_s;
+          end if;
+        when hit0_s =>
+          led_o <= "10000";
+          if key_i = '1' then
+            next_state <= chance_s;
+          elsif onesec_i = '1' then
+            next_state <= hit1_s;
+          end if;
+        when hit1_s =>
+          led_o <= "00001";
+          if key_i = '1' then
+            next_state <= chance_s;
+          elsif onesec_i = '1' then
+            next_state <= hit0_s;
+          end if;         
+        when others => null;
+      end case;
+    end process;
+        
+end architecture rtl;