module rom #(
  parameter string           FILE_NAME = "",
  parameter integer unsigned ADDR_W = 8,
  parameter integer unsigned DATA_W = 8
) (
  input  logic              clk,
  input  logic              nreset,

  input  logic              cs_i,
  input  logic [ADDR_W-1:0] address_i,
  output logic [DATA_W-1:0] rdata_o
);

localparam ROM_SIZE = 2**ADDR_W;

logic [DATA_W-1:0] rom [ROM_SIZE-1:0];
logic [DATA_W-1:0] rdata;

always_ff @(posedge clk or negedge nreset) begin
  if (!nreset)
    rdata <= '0;
  else
    rdata <= rom[address_i];
end

assign rdata_o = {8{cs_i}} & rdata;

initial begin
    static integer fd = $fopen(FILE_NAME, "rb");
    static integer rv = $fread(rom, fd);
end

endmodule : rom