Signal: detect eventFollowMe:
×
1. sc_event& default_event(), sc_event& value_changed_event(): return a reference to the value-changed event.
2. bool event(): return true if and only if the value of the signal changed in the update phase of the immediately preceding delta cycle and at the current simulation time.
run
Learn with Examples, 2020, MIT license
#include <systemc>
using namespace sc_core;
SC_MODULE(SIGNAL_EVENT) {
defines two signal channels
  sc_signal<int> s1, s2;
  SC_CTOR(SIGNAL_EVENT) {
    SC_THREAD(producer1);
    SC_THREAD(producer2);
consumer sensitive to (s1 OR s2)
    SC_THREAD(consumer);
same as: sensitive << s1.default_event() << s2.value_changed_event();
    sensitive << s1 << s2;
    dont_initialize();
  }
  void producer1() {
    int v = 1;
    while (true) {
write to s1
      s1.write(v++);
      wait(2, SC_SEC);
    }
  }
  void producer2() {
    int v = 1;
    while (true) {
write to s2
      s2 = v++;
      wait(3, SC_SEC);
    }
  }
  void consumer() {
    while (true) {
both triggered
      if ( s1.event() == true && s2.event() == true) {
        std::cout << sc_time_stamp() << ": s1 & s2 triggered" << std::endl;
only s1 triggered
      } else if (s1.event() == true) {
        std::cout << sc_time_stamp() << ": s1 triggered" << std::endl;
only s2 triggered
      } else {
        std::cout << sc_time_stamp() << ": s2 triggered" << std::endl;
      }
      wait();
    }
  }
};
int sc_main(int, char*[]) {
  SIGNAL_EVENT signal_event("signal_event");
  sc_start(7, SC_SEC);
  return 0;
}
Result:
s1 at 0, 2, 4, 6 s
s2 at 0, 3, 6 s
both
0 s: s1 & s2 triggered
s1 only
2 s: s1 triggered
s2 only
3 s: s2 triggered
s1 only
4 s: s1 triggered
both
6 s: s1 & s2 triggered
⇦ Signal: read and write     Signal: many writers ⇨