Virtual Devices (3.1) (vdag31qh.hlp) (Table of Contents; Topic list)
VDMAD_Disable_Translation
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include vdmad.inc
 
VxDcall VDMAD_Disable_Translation
 
The VDMAD_Disable_Translation service disables the automatic translation
done for the standard DMA channels. It is necessary if a V86 application or
driver or a PM application uses the DMA services through Interrupt 4Bh to
determine actual physical addresses for DMA transfers. A disable count is
maintained, so a matching call to VDMAD_Enable_Translation is required for
each call to this service to re-enable translation.
 
Parameter  Description
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EAX        Specifies the DMA handle.
 
EBX        Specifies the virtual machine handle.
 
Return Value
 
The carry flag is clear is automatic translation is disabled for the
channel. Otherwise, the carry flag is set if the disable count overflowed.
 
Uses
 
Flags
 
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