Hand Held Products 4X00, Руководство пользователя

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IMAGETEAM™ 4X00 Series Hardware Interface Layer Specification 5
FreePhysicalScanSpaceICMedia
This function frees the physical memory for a single image.
DWORD FreePhysicalScanSpaceICMedia(
DWORD hImage
)
Passed Arguments Description
DWORD hImage A "pseudo-handle" to a reserved physical memory slot. This was the value returned by
AllocatePhysicalScanSpaceICMedia when the space was allocated.
Returns
DWORD - This function returns non-zero on success, zero on failure.
GetFrequencyPerFrameOfLineDataCallbackICMedia
This function returns the number of calls made to the image line data callback function during each frame. When using an
operating system such as Windows CE, it may be difficult to tell consistently how many callbacks may be made per frame. In
that case, make a low estimate. Therefore, if on a given system the callback may be called from 28-33 times, a safe number
would be 27.
DWORD GetFrequencyPerFrameOfLineDataCallbackICMedia(
void
)
Returns
A number 'N' that completes this statement, "the line processing occurs at least 'N' times per frame."
GetHardwareDllRevisionICMedia
This function returns a revision number of the hardware DLL. The functions included with any given revision of the hardware
DLL are determined by this number. This guarantees that if the Image Acquisition Layer driver software is updated, but a
hardware DLL has not been updated, the software will be backward compatible. This document represents what should be
included in revision 1 of the hardware DLL.
Note: This function can be used as a general hardware layer initialization function since it is only called by the scan driver one
time, and it does not have the limitations of a base DLL initialization (for example, it can’t call Win32 API functions).
DWORD GetHardwareDllRevisionICMedia(
void
)
Returns
Revision number of the hardware DLL.