fork join
Fork-Join will start all the processes inside it parallel and wait for the completion of all the processes.
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fork join example
In below example,
fork block will be blocked until the completion of process-1 and Process-2.
Both process-1 and Process-2 will start at the same time, Process-1 will finish at 5ns and Process-2 will finish at 20ns. fork-join will be unblocked at 20ns.
module fork_join; initial begin $display("-----------------------------------------------------------------"); fork //------------------- //Process-1 //------------------- begin $display($time,"\tProcess-1 Started"); #5; $display($time,"\tProcess-1 Finished"); end //------------------- //Process-2 //------------------- begin $display($time,"\tProcess-2 Started"); #20; $display($time,"\tProcess-2 Finished"); end join $display($time,"\tOutside Fork-Join"); $display("-----------------------------------------------------------------"); $finish; end endmodule
Simulator Output
----------------------------------------------------------------- 0 Process-1 Started 0 Process-2 Startedt 5 Process-1 Finished 20 Process-2 Finished 20 Outside Fork-Join -----------------------------------------------------------------