_primary.vhd

用Verilog实现8255芯片功能

library verilog;
use verilog.vl_types.all;
entity data_bus_buf is
    port(
        lk_bus          : in     vl_logic;
        d_outbuf        : in     vl_logic_vector(7 downto 0);
        d_inbuf         : out    vl_logic_vector(7 downto 0);
        data_bus        : inout  vl_logic_vector(7 downto 0)
    );
end data_bus_buf;