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EVENT SYNC

Event Methods:

Events are variables that synchronize concurrent processes. When a sync is called, a process blocks until another process sends a trigger to unblock it. Events act as the go-between for triggers and syncs.

sync() ::This method synchronizes statement execution to one or more triggers.

ALL :::The ALL sync type suspends the process until all of the specified events are triggered.
For example:

sync(ALL, event_a, event_b, event_c);

ANY :::The ANY sync type suspends the process until any of the specified events is triggered.
For example:

sync(ANY, event_a, event_b, event_c);

ORDER :::The ORDER sync type suspends the process until any of the specified events is triggered.
For example:

sync(ORDER, event_a, event_b, event_c);

CHECK :::The CHECK sync type is called as a function. It does not suspend the thread. It returns a 1 if the trigger is ON and a 0 if it is not.This sync type can only be used with ON and OFF trigger types.This sync type can only be used with a single event per call.
For example:

sync(CHECK,event_a);

EXAMPLE : sync ANY

#include "vera_defines.vrh"
program main {
event event1,event2;
call();
sync(ANY,event1,event2);
printf(" time : %0d After sync \n",get_time(LO) );
delay(40);
printf(" END OF SIMUALTION \n");
}

task call(){
fork
{
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO)) ;
trigger(event1);
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO) );
trigger(event2);
}
join none
}

RESULTS

time : 10 , triggering event1
time : 10 After sync
time : 20 , triggering event1
END OF SIMUALTION

EXAMPLE : sync ALL

#include "vera_defines.vrh"
program main {
event event1,event2;
call();
sync(ALL,event1,event2);
printf(" time : %0d After sync \n",get_time(LO) );
delay(40);
printf(" END OF SIMUALTION \n");
}

task call(){
fork{
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO) );
trigger(event1);
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO) );
trigger(event2);
}
join none
}

RESULTS

time : 10 , triggering event1
time : 20 , triggering event1
time : 20 After sync
END OF SIMUALTION

EXAMPLE : sync ORDER

#include "vera_defines.vrh"
program main {
event event1,event2;
call();
sync(ORDER,event2,event1);
printf(" time : %0d After sync \n",get_time(LO) );
delay(40);
printf(" END OF SIMUALTION \n");
}

task call(){
fork{
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO) );
trigger(event2);
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO) );
trigger(event1);
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO) );
trigger(event2);
}
join none
}

RESULTS

time : 10 , triggering event1
time : 20 , triggering event1
time : 20 After sync
time : 30 , triggering event1
END OF SIMUALTION

EXAMPLE : sync CHECK

#include "vera_defines.vrh"
program main {
event event1,event2;
bit check_bit;
call();
check_bit = sync(CHECK,event1);
printf(" time : %0d After sync check_bit is %d \n",get_time(LO),check_bit);
delay(40);
printf(" END OF SIMUALTION \n");
}

task call(){
fork{
trigger(ON,event1);
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO) );
trigger(event1);
delay(10);
printf("time : %0d , triggering event1 \n",get_time(LO) );
trigger(event2);
}
join

RESULTS

time : 0 After sync check_bit is 1
time : 10 , triggering event1
time : 20 , triggering event1
END OF SIMUALTION

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