vhdl-car park monitoring system

To add more:

First you need to define your VHDL module Inputs/outputs. I suggest these as possible candidates, plus others as needed:

inputs:

reset (std_logic)

clk (std_logic)

car_in(std_logic)

car_out(std_logic)

midnight_sync(std_logic)

outputs:

error(std_logic)

full(std_logic)

empty(std_logic)

number_of_cars_in(std_logic_vector(1023 downto 0)

With regard to time of entry etc. You will need to have a separate module to generate time clock.