module oh_arbiter
  #( parameter N    = 1,
     parameter TYPE = "FIXED" // or ROUNDROBIN, FAIR
     )
   (
    input [N-1:0]  requests, //request vector
    output [N-1:0] grants    //grant (one hot)
    );

   wire [N-1:0]   waitmask;
   genvar 	  j;
   generate
      if(TYPE=="FIXED")
	begin : arbiter_fixed
	   assign waitmask[0]   = 1'b0;
	   for (j=N-1; j>=1; j=j-1)
	     begin : gen_arbiter
		assign waitmask[j] = |requests[j-1:0];
	     end
	end
   endgenerate

   //grant circuit
   assign grants[N-1:0] = requests[N-1:0] & ~waitmask[N-1:0];

endmodule // oh_arbiter