The Dink Network

sp_pframe(sprite, frame) will change the frame, so you just need to add a variable that keeps count of how many times you hit it.

//for example
void hit (void)
{
  &counter += 1;
  if (&counter >= 5)
  {
    sp_pframe(&current_sprite, 3);
  }
  if (&counter >= 10)
  {
    sp_pframe(&current_sprite, 7);
  }
  //etc etc etc etc etc
}