Instruction manual

SEE ALSO: EL_ACQUISITIONMODE, el_OpenHW , el_NewMemBuffer
5.2.3. el_AcquireEx
long
el_AquireEx (long BoardId, EL_ACQUISITIONMODE Mode, long *pChannels, long
*pStart, long *pLength, long NoOfChan, long Reserved);
Starts acquisition for a single frame/field (snap) or for continuous (live) acquisition
PARAMETERS:
BoardId : board ID returned by el_OpenHW
Mode:
• live: EL_LIVE
• snap: EL_SNAP
• or be aborted: EL_ABORT
pChannels: is intended to select specific channles, not used at the moment set to 0
pStart: array with index of start frame, for each channel
pLength: array with length of each sub sequence, for each channel
NoOfChan: length of arrays used before, 4 for most grabbers, 1 for
Reserved: set to 0
RETURN VALUE:
0 if OK
-1 if ERROR See el_GetErrorCode for details.
DESCRIPTION:
This function is an extended version of el_Acquire . for a geneal description have a look there.
el_AcquireEx is used to start an aquisiton on the given chanels filling just a part of the originally allocated
sequence(s). The start positions for each channel have to be stored in the pStart array. The length of the
sequences in the pLength array.
Future versions of the software might use the pChannels array to select special DMA channels. At the
moment a 0 pointer has to be used for pChannels and all channels are set up by the function. So
NoOfChan has to be ser to 1 for and to 4 for all other grabbers.
It is possible to assign one buffer to more than one channel. If one buffer withe the sequence length
SEQ_LEN has been assigned to all DMA channels the example below would fill the first quater of the
buffer with data from the first camera, the second quater with dater from the second camera and so on.
An overlapping of subsequences in one buffer is not allowed and can lead to unpredictable effects.
EXAMPLE :
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