GPSpvt
Reading Position, Velocity, Time from a GARMIN GPS via native USB
... GPS with USB port, and print out device info. But to get viable PVT data, the GPS must support A800 protocol / D800 datatype.
For reference see the document: 'Garmin Device Interface Specification, May 19, 2006, May 19, 2006, Drawing Number: 001-00063-00 Rev. C'
(file: Garmin Device Interface Specification (May 19, 2006).pdf).
Make sure the kernel module 'garmin_gps' is *NOT* loaded; otherwise USB is blocked!
Requires Python Version 3.x (developed on 3.5.2).