Category: <b>disk I/O enhancements</b>
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<pre><b>INT 4B - Virtual DMA Specification - REQUEST DMA BUFFER</b>

	AX = 8107h
	DX = flags
	    bit 0: reserved (zero)
	    bit 1: data should be copied into buffer
	    bits  2-15 reserved (zero)
	ES:DI -&gt; DMA descriptor structure (see <a href=../../it/21/32.html>#03221</a>) with region size set
		  (also region offset and region segment if DX bit 1 set)
Return: CF clear if successful
	    DDS physical address and buffer ID set
	    DDS region size filled with length of buffer
	CF set on error
	    AL = error code (see <a href=../../it/18/32.html>#03218</a>)
SeeAlso: AX=8108h
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