INT 21 - DOS 2+ internal - TRANSLATE BIOS PARAMETER BLOCK TO DRIVE PARAM BLOCK
AH = 53h
DS:SI -> BIOS Parameter Block (see below)
ES:BP -> buffer for Drive Parameter Block (see AH=32h for format)
Return: ES:BP buffer filled
Note:   for DOS 3+, the cluster at which to start searching is set to 0000h
and the number of free clusters is set to FFFFh (unknown)

Format of BIOS Parameter Block:
Offset  Size    Description
00h    WORD    number of bytes per sector
02h    BYTE    number of sectors per cluster
03h    WORD    number of reserved sectors at start of disk
05h    BYTE    number of FATs
06h    WORD    number of entries in root directory
08h    WORD    total number of sectors
for DOS 4+, set to zero if partition >32M, then set DWORD at
15h to actual number of sectors
0Ah    BYTE    media ID byte
0Bh    WORD    number of sectors per FAT
---DOS 3+---
0Dh    WORD    number of sectors per track
0Fh    WORD    number of heads
11h    DWORD   number of hidden sectors
15h 11 BYTEs   reserved
---DOS 4+ ---
15h    DWORD   total number of sectors if word at 08h contains zero
19h  6 BYTEs   ???
1Fh    WORD    number of cylinders
21h    BYTE    device type
22h    WORD    device attributes (removable or not, etc)
---European MSDOS 4.00---
15h    DWORD   total number of sectors if word at 08h contains zero
(however, this DOS does not actually implement >32M partitions)


2153 - DOS 2+ internal - TRANSLATE BIOS PARAMETER BLOCK TO DRIVE PARAM BLOCK