The magstripe module provides support for generic magstripe reading on the V4 Controller only.
This is a high level interface to magstripe reading. Allocate a new instance using magstripe.new().
The reader can be controlled using magstripe:enable(), magstripe:disable(), magstripe:trigger().
A callback named magstripe.magdataChanged() reports whenever a new card was read.
The raw data must be decoded using magstripe.decode().