Category: <b>disk I/O enhancements</b>
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<pre><b>INT 4B - Virtual DMA Specification (VDS) - GET VERSION</b>

	AX = 8102h
	DX = 0000h
Return: CF clear if successful
	    AH = major version number
	    AL = minor version number
	    BX = product number (see <a href=../../it/17/32.html>#03217</a>)
	    CX = product revision number
		always 0000h for QMAPS and HPMM.SYS
		always 0001h for Microsoft's EMM386.EXE v4.20-4.41
	    DX = flags (see <a href=../../it/19/32.html>#03219</a>)
	    SI:DI = maximum DMA buffer size
	CF set on error
	    AL = error code (see <a href=../../it/18/32.html>#03218</a>)
Note:	bit 5 of 0040h:007Bh is supposed to be set if VDS is supported; this is
	  apparently not always the case
SeeAlso: INT 2C/AX=002Bh,INT 31/AX=0400h,MEM 0040h:007Bh"4Bh"
Index:	installation check;Virtual DMA Specification

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