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//-----------------------------------------------------
// Design Name : ram_sp_ar_sw
// File Name : ram_sp_ar_sw.v
// Function : Asynchronous read write RAM
// Coder : Deepak Kumar Tala
//-----------------------------------------------------
module ram_sp_ar_sw (
clk , // Clock Input
address , // Address Input
data , // Data bi-directional
cs , // Chip Select
we , // Write Enable/Read Enable
oe // Output Enable
);
parameter DATA_WIDTH = 8 ;
parameter ADDR_WIDTH = 8 ;
parameter RAM_DEPTH = 1 << ADDR_WIDTH;
//--------------Input Ports-----------------------
input clk ;
input [ADDR_WIDTH-1:0] address ;
input cs ;
input we ;
input oe ;
//--------------Inout Ports-----------------------
inout [DATA_WIDTH-1:0] data ;
//--------------Internal variables----------------
reg [DATA_WIDTH-1:0] data_out ;
reg [DATA_WIDTH-1:0] mem [0:RAM_DEPTH-1];
//--------------Code Starts Here------------------
// Tri-State Buffer control
// output : When we = 0, oe = 1, cs = 1
assign data = (cs && oe && !we) ? data_out : 8'bz;
// Memory Write Block
// Write Operation : When we = 1, cs = 1
always @ (posedge clk)
begin : MEM_WRITE
if ( cs && we ) begin
mem[address] = data;
end
end
// Memory Read Block
// Read Operation : When we = 0, oe = 1, cs = 1
always @ (address or cs or we or oe)
begin : MEM_READ
if (cs && !we && oe) begin
data_out = mem[address];
end
end
endmodule // End of Module ram_sp_ar_sw
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