Component Declaration and Instantiation

Next-level of hierarchy design must have a Component Declaration for a lower-level design before it can be Instantiated

Component Declaration

Component Instantiation

Instance label/name

Positional Association

ARCHITECTURE tolleab_arch OF tolleab IS

COMPONENT tollv

PORT( clk : IN STD_LOGIC;

cross, nickel, dime, quarter : IN STD_LOGIC;

green, red : OUT STD_LOGIC;

sout : OUT STATE_TYPE;

state_in : IN STATE_TYPE);

END COMPONENT;

BEGIN

u1 : tollv PORT MAP ( tclk, tcross, tnickel, tdime,

tquarter, tgreen, tred,

tsout, tstate);

Next-level of hierarchy design must have a Component Declaration for a lower-level design before it can be Instantiated