I have been messing around with this GPS HAT for a few days now. I do have it working, although I have multiple modules running at once on stacked breadboards.
My main question is on AdaFruit's website, they claim the GPS's PPS module (when a fix is acquired) is on pin #4. When I look at the Raspi-Pi GPIO pinout, it shows this as 5VDC. How can this be, if it is transferring data serially?
EDIT: I have the Raspberry Pi Model B+ V1.2 if that makes any difference.