1 files changed, 24 insertions, 2 deletions
diff --git a/src/dispshift.vhd b/src/dispshift.vhd
index 5669641..4c4093b 100644
--- a/src/dispshift.vhd
+++ b/src/dispshift.vhd
@@ -11,7 +11,29 @@ end dispshift;
 
 architecture Behavioral of dispshift is
 
-begin
-
+-- init as empty display
+signal sD: std_logic_vector(11 downto 0) := x"aaa";
+signal SLastValue: std_logic := '0';
 
+begin
+    process(CLK)
+    begin
+        if (rising_edge (clk)) then
+            -- set default values
+            SLastValue <= S;
+            sD <= sD;
+            
+            -- when S does go high update output
+            if (SLastValue = '0' and S = '1') then   
+                -- set data on output             
+                N3 <= sD(11 downto 8);
+                N2 <= sD(7 downto 4);
+                N1 <= sD(3 downto 0);
+                N0 <= D; 
+                
+                -- store new data
+                sD <= sD(7 downto 0) & D;
+            end if;
+        end if;    
+    end process;
 end Behavioral;