a question regarding paramters to the tasks

[Amir]

Hi,
is there a way where I can in do in Verilog such in the following
psuedo-code example?:

task hello;
input a;
input b;

if (be "not-defined")
then random(b);

...

endtask

thanks
-Amir

 

[Jonathan Bromley]

On Tue, 12 May 2009 00:08:13 -0700 (PDT), Amir wrote:

is there a way where I can in do in Verilog such in the following
psuedo-code example?:

task hello;
input a;
input b;

Probably best to talk about task "arguments" in Verilog;
"parameter" means something very different.

if (be "not-defined")
then random(b);

I guess you mean
if the caller did not supply a value for argument "b",
then give it my custom random value
??

The answer in Verilog is "no". In SystemVerilog you can
give tasks default arguments:

task hello(input a, input b = 1'bx);

and now, if the user calls hello(1), your task
will effectively see hello(1, 1'bx). You can
then test for the default value inside the task.

HTH
--
Jonathan Bromley, Consultant

DOULOS - Developing Design Know-how
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The contents of this message may contain personal views which
are not the views of Doulos Ltd., unless specifically stated.

 

[Dave Rich]

A simpler solution, if all you wanted to do was randomize an
unspecified input would be

task hello(input int A, B=$random);

....

endtask

On May 12, 12:19 am, Jonathan Bromley <jonathan.brom...@MYCOMPANY.com>
wrote:

On Tue, 12 May 2009 00:08:13 -0700 (PDT), Amir wrote:
is there a way where I can in do in Verilog such in the following
psuedo-code example?:

task hello;
 input a;
 input b;

Probably best to talk about task "arguments" in Verilog;
"parameter" means something very different.

if (be "not-defined")
then random(b);

I guess you mean
  if the caller did not supply a value for argument "b",
  then give it my custom random value
??

The answer in Verilog is "no".  In SystemVerilog you can
give tasks default arguments:

  task hello(input a, input b = 1'bx);

and now, if the user calls hello(1), your task
will effectively see hello(1, 1'bx).  You can
then test for the default value inside the task.