Intel cPCI-7200 - Manual (Page 54)

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• C/C++ Libraries
5.14 _7200_Free_DMA_Mem
@ Description
Releases system DMA memory. This function is only available in Windows
95/98.
@ Syntax
Visual C++ (Windows 95)
int W_7200_Free_DMA_Mem (U32 handle)
Visual Basic (Windows 95)
W_7200_Free_DMA_Mem (ByVal handle As Long ) As Long
@ Argument
handle: The handle of system DMA memory to release.
@ Return Code
ERR_NoError
5.15 _7200_Alloc_DBDMA_Mem
@ Description
Contact Windows 95/98 system to allocate a block of contiguous memory as
circular buffer for double-buffered DMA DI transfer. This function is only
available in Windows 95/98 version. For double-buffered transfering, please
refer to Section 6 “Double Buffered Mode Principle”.
@ Syntax
Visual C++ (Windows 95)
int W_7200_Alloc_DBDMA_Mem (U32 *buff,U32 *handle, U32
buf_size, U32 *actual_size)
Visual Basic (Windows 95)
W_7200_Alloc_DBDMA_Mem (buff As Long, handle As Long, ByVal
buf_size As Long, actual_size As Long) As Long
@ Argument
buff:
There is a dummy buffer attached to the DMA memory this function will
allocate. But this buffer needs to have size equal to or more than buf_size
bytes.
handle:
The handle of system DMA memory returned from system. Use this
handle in _7200_DI_DMA_Start.
buf_size:
Bytes to allocate. This is the half size of circular buffer in byte.
That is, this is the size of each half buffer in byte.
actual_size:
The actual DMA memory size system allocate for each half
buffer. If system is not able to get a block of contiguous memory of specified
buf_size
, it will allocate a block of memory as large as it can. In this case,
this function returns ERR_SmallerDMAMemAllocated, and actual_size