Can a Verilog function take a boolean argument?

Sep 17, 2020 1 Replies

I've got a Verilog function that I'd like to behave slightly differently depending on the value of a boolean argument, an argument whose value can be either (true) or (false). I tried:

  module sid ();



function integer execOp; input integer left; input integer right; input boolean add; begin execOp = add ? left + right : left * right; end endfunction



endmodule

Then when I use Icarus to simulate it I get:
  D:\Hf\Verilog\Unpacked\Common>\Icarus\bin\iverilog -g2009 -o sid.out sid.sv  sid.sv:6: syntax error  sid.sv:3: error: Syntax error defining function.



D:\Hf\Verilog\Unpacked\Common>

Line 6 is the line where I declare variable (add). Is there a way to pass a boolean argument to a function, or am I going to have to declare an (enum) that has values (true) and (false)?


There is no "Boolean" type in Verilog, as far as I know. The default type is a 1-bit register that is fairly equivalent. If you just delete the word "boolean" from your example, it should work.

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