Category: <b>DOS kernel</b>
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<pre><b>INT 21 - DOS 2+ internal - TRANSLATE BIOS PARAMETER BLOCK TO DRIVE PARAM BLOCK</b>

	AH = 53h
	DS:SI -&gt; BIOS Parameter Block (see <a href=../../it/63/16.html>#01663</a>)
	ES:BP -&gt; buffer for Drive Parameter Block (see <a href=../../it/95/13.html>#01395</a> at AH=32h)
	    DBP drive byte must be set to valid drive (Windows95-OSR2)
	---Windows95---
	CX = signature 4558h ('EX') for FAT32 extended BPB/DPB (see <a href=../../it/64/16.html>#01664</a>)
	DX = signature 4152h ('AR') for FAT32 extended BPB/DPB
Return: ES:BP buffer filled
Notes:	for DOS 3.0+, the cluster at which to start searching is set to 0000h
	  and the number of free clusters is set to FFFFh (unknown)
	if the number of sectors per cluster is set to zero, MS-DOS will hang
	  at startup because it computes the internally-used shift count by
	  shifting this value right until the carry flag is set; since this
	  will never happen when the field is zero, MS-DOS hangs
	not supported by Windows NT 3.1

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