booth_multiplier.v

Booth multiplier written in verilog

`include "parameters.h"
module booth_multiplier ( Result , Xin, Yin );

input [`X_WIDTH - 1 :0 ] Xin;
input [`Y_WIDTH - 1 :0 ] Yin;

output [`X_WIDTH + `Y_WIDTH - 1 : 0] Result;
reg [`X_WIDTH + `Y_WIDTH - 1 : 0] Result;

integer i;
reg [`Y_WIDTH : 0] Yin_int;
reg [`X_WIDTH + `Y_WIDTH - 1 : 0] Mul = 24'b0;

// assign Yin_int = { Yin , 1'b0 } ;

always @ ( Xin or Yin) begin
Yin_int = { Yin , 1'b0 } ;
$display( "I M here 1" ) ;
for ( i =  `Y_WIDTH ; i >= 2 ; i = i - 2 ) begin 
Mul = Mul << 1 ;
$display( "I M here 2" ) ;
     $display( "Value of Yin_int = %h", Yin_int ) ;
       case (Yin_int[`Y_WIDTH : `Y_WIDTH -2])
             0 | 7 : begin 
		     Mul = Mul ;
		     $display( "I M here 3" ) ;
		     end
             1 | 2 : begin
		     Mul = Mul + Xin ;
		     $display( "I M here 4" ) ;
		     end
             3     : begin
			Mul = Mul + {Xin, 1'b0} ;
		     $display( "I M here 5" ) ;
		     end

             4     : begin 
			Mul = Mul + {((~Xin) + 1), 1'b0} ;
		     $display( "I M here 6" ) ;
		     end
			
             5 | 6 : begin 
			Mul = Mul + (~Xin) + 1 ;
		     $display( "I M here 7" ) ;
		     end

       endcase
Yin_int = Yin_int << 3;
end
Result = Mul ; 
end 
endmodule