| 1 | --+-----------------------------------------+ |
| 2 | --| pfs | |
| 3 | --+-----------------------------------------+ |
| 4 | |
| 5 | library ieee; |
| 6 | use ieee.std_logic_1164.all; |
| 7 | |
| 8 | entity pfs is |
| 9 | port ( |
| 10 | clk : in std_logic; |
| 11 | a : in std_logic; |
| 12 | y : out std_logic |
| 13 | |
| 14 | ); |
| 15 | end pfs; |
| 16 | |
| 17 | architecture rtl of pfs is |
| 18 | |
| 19 | signal a_s : std_logic; |
| 20 | |
| 21 | begin |
| 22 | |
| 23 | SYNCP: process( clk, a ) |
| 24 | begin |
| 25 | |
| 26 | if ( rising_edge(clk) ) then |
| 27 | a_s <= a; |
| 28 | end if; |
| 29 | |
| 30 | end process SYNCP; |
| 31 | |
| 32 | y <= a and (not a_s); |
| 33 | |
| 34 | end rtl; |
| 35 | |