Intel LPCI-7200S 5.14 7200FreeDMAMem, 5.15 7200AllocDBDMAMem, @ Description, @ Syntax, @ Argument

Models: LPCI-7200S

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5.14 _7200_Free_DMA_Mem

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

46 C/C++ Libraries

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Intel LPCI-7200S 5.14 7200FreeDMAMem, 5.15 7200AllocDBDMAMem, @ Description, @ Syntax, Visual C++ Windows, @ Argument