Virtual Devices (3.1) (vdag31qh.hlp) (Table of Contents; Topic list)
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VDMAD_Unlock_DMA_Region
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include vdmad.inc
 
VxDcall VDMAD_Unlock_DMA_Region
 
The VDMAD_Unlock_DMA_Region service unlocks the DMA region previously locked
to a channel. It is called after a DMA transfer is complete and the channel
has been masked,preventing the controller from attempting any further
transfers to the programmed address.
 
Parameter  Description
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ESI        Specifies the linear address of the actual DMA region.
 
ECX        Specifies the number of bytes in the DMA region.
 
Return Value
 
The carry flag is clear if the memory is unlocked. Otherwise, the carry flag
is set to indicate an error.
 
Uses
 
Flags
 
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