Clearing the mailbox in system verilog

[rkini]

Is it possible to clear the mailbox contents?? Say if I want to flush out the contents of the mailbox at a certain point in my code, is there a way to do that???

 

[dave_59]

You have to do this in a loop with try_get

while (my_mailbox.try_get(tx)) ; //this does a flush of the mailbox


The only problem with this is if you have pending blocked get()s on the same fifo. this code might not work properly ( a race) See http://www.eda.org/svdb/view.php?id=1738

 

[rkini]

Will this approach also work if I havent bounded my mailbox?? I mean the try_get gets values only for the number of times of the contents and not the size of the mailbox, am I correct?

 

[dave_59]

Bounding your mailbox only affects put(). try_get() gets one item at a time.

 

[rkini]

I have an environment class where i define a mailbox and construct its object as follows:
class environment;

mailbox driver2sb;

function void build()
driver2sb = new();// driver to scoreboard mailbox

endclass
In the scoreboard class i try to do :

class scoreboard;

mailbox driver2sb;

task start();

.....
.....
.....

while(driver2sb.try_get());
begin
$display("Clearing driver mailbox");
end

endclass

However I get the following error message:

errors: 0, warnings: 0
while(driver2sb.try_get());
|
ncvlog: *E,FAABPB (scoreboard.sv,52|22): task or function call does not specify all required formal arguments [10.2.2][10.3(IEEE)].
while(out2sb.try_get());


I dont know what I am doing wrong!

 

[dave_59]

The error message told you clearly what you are doing wrong.