SimplifiedBACnetStackExample.c

int main() {
   ConnectUDP();
   SetupCallbacks();
   
   AddDevice(389001) ;
   AddObject(389001, ANALOG_INPUT, 101);
   AddObject(389001, BINARY_OUTPUT, 102);
   AddObject(389001, MULTI_STATE_VALUE, 103);
   ...

   for(;;) {
       BACnetLoop();
   }
}
bool CallbackGetPropertyReal(uint32_t deviceInstance, uint16_t objectType, 
                             uint32_t objectInstance, uint32_t propertyIdentifier, 
                             float * value, bool useArrayIndex, uint32_t propertyArrayIndex)
{
   if (propertyIdentifier == PROPERTY_IDENTIFIER_PRESENT_VALUE) {
      if (objectType == ANALOG_INPUT && objectInstance == 101) {
         *value = 99.6;
         return true;
      }
   }
   return false; 
}
void CallbackReceiveMessage(...) {...};
void CallbackSendMessage(...) {...};