Returns the total number of files that can be simultaneously stored on the currently existing flash disk.
Value depends on the current disk formatting.
Formatting the Flash Disk, Creating, Deleting, and Renaming Files, Checking Disk Vitals,
fd.capacity, fd.numservicesectors, fd.totalsize, fd.getfreespace, fd.getnumfiles
This number cannot be changed unless the disk is reformatted (see fd.formatj).
The disk must be mounted (see fd.mount) for this property to return a meaningful value.