1 files changed, 28 insertions, 0 deletions
diff --git a/smh-ac415-fpga/lcd_driver/edge_det.vhdl b/smh-ac415-fpga/lcd_driver/edge_det.vhdl
new file mode 100644
index 0000000..8cb38eb
--- /dev/null
+++ b/smh-ac415-fpga/lcd_driver/edge_det.vhdl
@@ -0,0 +1,28 @@
+library IEEE;
+use IEEE.STD_LOGIC_1164.all;
+
+entity edge_det is
+    port (clk : in  std_logic;
+          sig : in  std_logic;
+          pe  : out std_logic;
+          ne  : out std_logic;
+          e   : out std_logic
+          );
+end edge_det;
+
+architecture Behavioral of edge_det is
+    signal last : std_logic := '0';
+begin
+
+    process(clk,last,sig) 
+    begin
+        if rising_edge(clk) then
+            last <= sig;
+        end if;
+    end process;
+
+    pe <= '1' when sig = '1' and last = '0' else '0';
+    ne <= '1' when sig = '0' and last = '1' else '0';
+
+    e <= sig xor last;
+end Behavioral;