Banderon

Does anyone know if the stamp can interface with the computer while running, or only while being programmed?

I know the Stamp 2p has 2 pins dedicated to serial I/O, but are those only used during programing or all the time? Basically, I want to be able to have control of my relays/sensors/components without having to wait for my PC to boot, so I'm using the stamp to control them. But once the PC boots, I want to be able to control the relays via windows, while still have the stamp's program running for automated functions (auto-headlights, auto-windows, etc.)