INT 21,1F - Get Pointer to Current Drive Parameter Table (Undocumented)

AH = 1F

DL = drive number (0=default, 1=A, ...)

on return:

AL = 00 DS:BX is pointer to drive parameter table (~DPT~)

FF drive does not exist

DS:BX = pointer to drive parameter table (DPT) if AL=0

- the format of the DPT varies between DOS versions

- calls ~INT 21,32~ with DL=00 for DOS version 2.x+