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signalswaitthread-sleepsystemc

Using wait statements with signals

Is it possible to use a wait statement with an input signal in a thread, i.e.

void Thread::myThread(){
   while(1){
      wait(mySignal);
      if(mySignal == 1){
         //do stuff
      }
   }
}

where mySignal is sc_in<int> mySignal;

I tried to run a similar variation, but i get the following error when i try to step over the wait statement. enter image description here

From what I've been able to read about waits, it seems they take time, events, and some other combinations, but not directly a signal.

Assuming i cannot use the signal directly inside the wait, could i achieve the same result by making the thread sensitive in the constructor, i.e.

SC_MODULE(myModule){
   sc_in<bool> mySignal;

   void myThread();

   SC_CTOR(myModule){
      SC_THREAD(myThread)
      sensitive << mySignal;
   }
}

void myModule::myThread(){
   while(1){
       wait(); //Wait for mySignal
        if(mySignal == 1){
           //do stuff
        }
    }
}
Solution

  • There are slight inconsistencies in your code. Try changing your code to this:

    SC_MODULE(myModule){
  sc_in<bool> mySignal;
  void myThread();
  SC_CTOR(myModule){
    SC_THREAD(myThread); //<< SC_THREAD is a macro.
    sensitive << mySignal;
  }
}

void myModule::myThread(){ //<< Did you mean this instead of Thread class
  while(1){
    wait(); //Wait for mySignal
    if(mySignal == 1){
      //do stuff
    }
  }
}