Phytec eGrabber-4plus, Hardware Manual

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Driver Software
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PHYTEC Meßtechnik GmbH 2004 L-608e_4
165
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Start grabbing
void Start_Grabber(unsigned short nDevNo);
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Stop grabbing
void Stop_Grabber(unsigned short nDevNo);
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Show digitization status
short Data_Present(unsigned short nDevNo);
return value: shows status of digitization
(values 0 - 15 (4-bit) )
DOS
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Interrupt Configuration
WORD Set_Interrupt(WORD nDevNO, DWORD nInterrupt);
NInterrupt: OFF = No interrupt generation (default)
VSYNC = Interrupt at the end of a half image
Return Value: Error Status
The eGrabber-4plus can generate an interrupt, if the end of a half-
image is recognized at the video input. If a digitalization procedure is
active, then it can be determined, with the aid of the interrupt and
without polling (see Data_Present), when this procedure is finished.
A digitalization procedure can only be complete at the end of a half
image, which is signaled by the interrupt. However, an interrupt
doesn’t absolutely mean that a digitalization procedure is complete,
because:
•
It may be the case that no digitalization procedure was active
(the Grabber is in rest state).
•
The most recently completed half image is not the one that is to be
digitalized (for example even instead of odd)