Configuration Specification:
Example

ENTITY JKFF IS 
   PORT (clk, preset, clear, J, K : IN BIT;
         Q, Q_bar : OUT BIT);
END JKFF;

PACKAGE Global_signals IS
   SIGNAL clk, preset, clear : BIT;
END PACKAGE Global_signals;

USE Work.Global_signals;

ENTITY config_test IS
END config_test;

ARCHITECTURE structural OF config_test IS
   SIGNAL S1, S2, S3, S4 : BIT;
   COMPONENT FF
     PORT (J, K: IN BIT; Q, Q_bar : OUT BIT);
   END COMPONENT FF;

   FOR UO : FF USE ENTITY Work.JKFF
     PORT MAP (clk => Global_signals.CLK,
       preset => Global_signals.preset,
       clear => Global_signals.clear,
        J => S1, K => S2,
        Q => S3, Q_bar => S4);

BEGIN
   UO : FF PORT MAP (S1, S2, S3, S4);
END structural;