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/****************************************************************************************
 MODULE:                Sub Level Memory Block

 FILE NAME:     mem.v
 VERSION:       1.0
 DATE:          September 28th, 2001
 AUTHOR:                Hossein Amidi
 COMPANY:       California Unique Electrical Co.
 CODE TYPE:     Behavioral Level

 Instantiations:
 
 DESCRIPTION:
 Sub Level Behavioral Memory Block, It uses 12 Address and 16 Data Line
 the memory size would be 2 ^ 12 = 4096 * 16-bit wide = 65536 bits.
 65536 bits / 8 = 8192 Byte ->  8K Byte of memory.

 This memory is organized as 4096 locations of 16-bit (2 Byte) wide.

 Hossein Amidi
 (C) September 2001
 California Unique Electric

***************************************************************************************/
 
`timescale 1ns / 1ps

module MEM (// Input
                                DataIn,
                                Address,
                                MemReq,
                                RdWrBar,
                                clock,
                                // Output
                                DataOut
                                );


// Parameter
parameter words = 4096;
parameter AccessTime = 0;
parameter DataWidth = 32;
parameter AddrWidth = 24;

// Input
input [DataWidth - 1 : 0] DataIn;
input [AddrWidth - 1 : 0] Address;
input MemReq;
input RdWrBar;
input clock;

// Output
output [DataWidth - 1 : 0] DataOut;

// Internal Memory Declerations
// 4096 x 16 bit wide

reg [DataWidth - 1 : 0] MEM_Data [0:words-1];

// Signal Declerations
wire [DataWidth - 1 : 0] Data;

// Assignments
// Read Cycle
assign Data = (MemReq && RdWrBar)? MEM_Data [Address]:32'hz;
assign #AccessTime DataOut = Data; // Delay in a continuous assign


// Write Cycle
always @(posedge clock)
begin
        if(MemReq && ~RdWrBar)
                MEM_Data [Address] <= DataIn;
end

endmodule