Before a car engine can be Cranked to start it the following

Before a car engine can be Cranked, to start it, the following conditions have to exist for a continuous duration of at least 50 ms: The engine must not be Running, the key must be in the Start position, and either the gear lever is in the Neutral position and the Brake is on or the gear lever is in the Park position. If any of the conditions isn’t met the timer restarts (from 0). Assign variable names (single capitals indicated) and their true states. Write Verilog code for the Crank signal. Assume that a 200 Hz clock signal is available.

Solution

LIBRARY ieee; USE ieee.std_logic_1164.ALL; ENTITY clk200Hz_tb IS END clk200Hz_tb; ARCHITECTURE behavior OF clk200Hz_tb IS COMPONENT clk200Hz PORT( clk_in : IN std_logic; reset : IN std_logic; clk_out: OUT std_logic ); END COMPONENT; -- Inputs signal clk_in : std_logic := \'0\'; signal reset : std_logic := \'0\'; -- Outputs signal clk_out : std_logic; constant clk_in_t : time := 50ms; BEGIN -- Instance of unit under test. uut: clk200Hz PORT MAP ( clk_in => clk_in, reset => reset, clk_out => clk_out ); -- Clock definition. entrada_process :process begin clk_in <= \'0\'; wait for clk_in_t / 2; clk_in <= \'1\'; wait for clk_in_t / 2; end process; -- Processing. stimuli: process begin reset <= \'1\'; -- Initial conditions. wait for 50 ms; reset <= \'0\'; -- Down to work! wait; end process; END;