How to Init device with same Command and Notify Port

I don't understand how i can `Init()` a device with same CommandPort and NotifyPort. `Open()` do not open NotifyPort if it is the same as CommandPort. Then, when you call Init(), it calls `sanityCheck()` and if notifyPort is not openned, it exit.
I have a very simple modem (SIM800C), looks like i do not have dedicated NotifyPort.