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Altera_Forum's avatar
Altera_Forum
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14 years ago

synthesis of several "if..if...if "sentence.

always @(posedge clk or negedge rst)begin if(!rst)begin ..... end else begin if(a) .... if(b) .... if(c) .... end end I found tha...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Yes by making multiple assignments in an if cascade you ended up coding priority into the assignment. You could do a one-hot mux like this assuming a, b, and c are asserted mutually exclusively: 

always @ (a or b or c)
begin
  case ({c, b, a})
    3'b001: <expression>;
    3'b010: <expression>;
    3'b100: <expression>;
    default:  <expression>;  // this case can never happen if only one of a, b, or c are ever enabled at any given time
  endcase
end