INT 4B - Virtual DMA SpecificationA set of interrupt calls which permit the use of DMA even on systems running in protected or Virtual-86 mode with their address remapping, or systems such as Micro Channel PSIBM PS/2, any model/2s with multiple bus masters independently performing DMA operations. - REQUEST DMAsee Direct Memory Access BUFFER AX = 8107h DX = flags bit 0: reserved (zero) bit 1: data should be copied into buffer bits 2-15 reserved (zero) ES:DI -> DMAsee Direct Memory Access descriptor structure (see #03221) 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 #03218) SeeAlso: AX=8108h