library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;

library design;
use design.all;

entity bench_top is
end entity bench_top;

architecture RTL of bench_top is
	signal clk    : std_logic;
	signal rst_hw : std_logic;

	signal lcd_data : std_logic_vector(3 downto 0);
	signal lcd_clp  : std_logic;
	signal lcd_load : std_logic;
	signal lcd_frp  : std_logic;
	signal lcd_frmb : std_logic;

	signal spi_cs_n : std_logic;
	signal spi_sck  : std_logic;
	signal spi_mosi : std_logic;
	signal spi_miso : std_logic;

begin
	top_inst : entity design.top
		port map(
			spi_cs_n => spi_cs_n,
			spi_sck  => spi_sck,
			spi_mosi => spi_mosi,
			spi_miso => spi_miso,
			clk_hw   => clk,
			rst_hw   => rst_hw,
			lcd_data => lcd_data,
			lcd_clp  => lcd_clp,
			lcd_load => lcd_load,
			lcd_frp  => lcd_frp,
			lcd_frmb => lcd_frmb
		);

	clock_driver : process
		constant period : time := (1 sec / 24000000);
	begin
		clk <= '0';
		wait for period / 2;
		clk <= '1';
		wait for period / 2;
	end process clock_driver;

	test : process is
	begin
		rst_hw <= '0';
		wait for 100 ns;
		rst_hw <= '1';
		wait;
	end process test;
	
	spitest : process is
		constant CPOL : std_logic := '0';
		constant DEL : time  := 400 ns;
		
		procedure send_byte(data : std_logic_vector(7 downto 0)) is
		
		begin
			for i in 7 downto 0 loop
				spi_sck <= CPOL;
				wait for DEL;
				spi_mosi <= data(i);
				spi_sck <= not CPOL;
				wait for DEL;
			end loop;
		end procedure send_byte;
		
	begin
		spi_cs_n <= '1';
		spi_sck <= '0';
		spi_mosi <= CPOL;
		
		wait until rst_hw = '1';
		wait until rising_edge(clk);
		wait until rising_edge(clk);
		wait until rising_edge(clk);
		wait until rising_edge(clk);
		wait until rising_edge(clk);
		spi_cs_n <= '0';
		wait for 400 ns;
		send_byte(x"00");
		send_byte(x"00");
		send_byte(x"00");
		
		send_byte(x"AB");
		send_byte(x"CD");
		send_byte(x"55");
		send_byte(x"AA");
		send_byte(x"81");
		
		send_byte(x"2A");
		send_byte(x"AB");
		send_byte(x"BC");
		send_byte(x"CF");
		
		send_byte(x"AB");
		send_byte(x"CD");
		send_byte(x"55");
		send_byte(x"AA");
		send_byte(x"81");
		
		send_byte(x"2A");
		send_byte(x"AB");
		send_byte(x"BC");
		send_byte(x"CF");
		
		spi_cs_n <= '1';
		
		wait;
	end process spitest;
	

end architecture RTL;