1 //===========================================
  2 // Function : ROM using readmemh
  3 // Coder    : Deepak Kumar Tala
  4 // Date     : 31-Oct-2005
  5 //===========================================
  6 module rom_using_file (
  7 input  wire [7:0] address , // Address input
  8 output wire [7:0] data    , // Data output
  9 input  wire       read_en , // Read Enable 
 10 input  wire       ce        // Chip Enable
 11 );
 12            
 13 reg [7:0] mem [0:255] ;  
 14       
 15 assign data = (ce && read_en) ? mem[address] : 8'b0;
 16 
 17 initial begin
 18   $readmemb("memory.list", mem); // memory_list is memory file
 19 end
 20 
 21 endmodule

You can find the rom model and testbench here and memory_list file here.

  1 //===========================================
  2 // Function : ROM using case
  3 // Coder    : Deepak Kumar Tala
  4 // Date     : 31-Oct-2005
  5 //===========================================
  6 module rom_using_case (
  7 input  wire [7:0] address , // Address input
  8 output reg  [7:0] data    , // Data output
  9 input  wire       read_en , // Read Enable 
 10 input  wire       ce        // Chip Enable
 11 );
 12 
 13 always_comb
 14 begin
 15   case (address)
 16     0 : data = 10;
 17     1 : data = 55;
 18     2 : data = 244;
 19     3 : data = 0;
 20     4 : data = 1;
 21     5 : data = 8'hff;
 22     6 : data = 8'h11;
 23     7 : data = 8'h1;
 24     8 : data = 8'h10;
 25     9 : data = 8'h0;
 26     10 : data = 8'h10;
 27     11 : data = 8'h15;
 28     12 : data = 8'h60;
 29     13 : data = 8'h90;
 30     14 : data = 8'h70;
 31     15 : data = 8'h90;
 32   endcase
 33 end
 34 
 35 endmodule

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Deepak Kumar Tala - All rights reserved

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