AVAL APX-3302, Руководство пользователя

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APX-3302 User's Manual (OM110000019A)
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Since “frame number which input completed (nFrameNo)”, the argument for callback function, counts up in
real time at DMA transfer, it skips “frame number which input completed” if call of callback is delayed and
executed after count-up.
Since DMA transfer itself is done without skipping, it can judge that number of images which frame counter
skipped was decided. (It means that finish transferring 2 frames if it skips to 3->5)
So if image process is carried out to memory of the increment of frame counter, it can restore delay.
[Troubleshoot issues of lost event]
If status which load is very high continues, next event notification, which is same, is preformed and
disappearance is occurred.
Since disappearance is caused by overwriting same event notification, skipped event is always notified. It is
able to follow if you do same measures as time of delay.
As these shows, it is able to restore delay by followings:
* Preparing multiple number of transfer destination memory
* Process the number of skipped frames
However, if skip exceeding number of transfer destination memory is occurred, overwrite of transfer
destination memory occurs. Also it is hard to restore delay if image processing is heavy load or needs long
time for performing.
In that situation, you need to do disposals like followings:
* Reduce CPU load
* Revise PC engine performance
* Reduce frame rate
* Reduce transferring amount (resolution) of 1 frame
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[1] nMemoryNo[1]
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[2] nMemoryNo[2]
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[3] nMemoryNo[3]
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[5] nMemoryNo[2] *1
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[5] nMemoryNo[2] *2
*1
：
Perform process for 2 frames (MemoryNo 1 or 2)
*2
： Do not perform anything since “frame number finished input” does not increase
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[1] nMemoryNo[1]
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[2] nMemoryNo[2]
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[3] nMemoryNo[3]
CallbackFunc called. nChannel[1] dwEvent[2] nFrameNo[5] nMemoryNo[2] * Frame 4 does not come