There's a decent level of darkness in the immediate area so star shots on a clear night are very achievable.
Setting up, use a torch to help you focus (shine it on your subject: the Tor, I guess) and also use your light to find the corners of your frame when composing.
You want the maximum light sensitivity for stars, so that's a high ISO and a wide aperture. Haven't visited the Tor at night for many years but I'd think ISO800 and f/2.8 would be easily possible, subject to your choice of camera and lens. Then use shutter speed to get the ambient light looking the way you want. Anywhere between 15 & 30 seconds will see you ok, but if you need to shoot longer than 30 seconds, try increasing the ISO instead until a 30 second frame gives the result you're looking for.
Once you're all set to go, set the camera into continuous high-speed firing mode and lock your shutter open with a cable or remote release. That should keep you firing until either your card's full or your battery's empty.
Once shooting, the main thing to beware of is condensation on your front element. No easy way to check for this but it usually follows about 15 minutes after starting on your tripod legs.
With an ultra-wide angle lens it's possible to compose circular star trails over the Tor, having found Polaris of course. I think it can also make a great shot to drop down the hill a little and shoot a wider landscape.
Good luck!