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authorJames McKenzie <root@ka-ata-killa.panaceas.james.local>2025-04-20 18:17:56 +0100
committerJames McKenzie <root@ka-ata-killa.panaceas.james.local>2025-04-20 18:17:56 +0100
commit6138bd2f72841f5af4bd7d8c089223be3fd23324 (patch)
treef20cbd6cba8369bf01eb33b362008f79eedcd9d9 /smh-ac415-fpga/lcd_driver/edge_det.vhdl
parentbc24ae901b74c5b673837d7f83423c1f7aa45c29 (diff)
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add noddy cyclone IV fpga design
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+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;