Phytec eGrabber-4plus, Руководство по оборудованию

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eGrabber-4plus
176 
PHYTEC Meßtechnik GmbH 2004 L-608e_4
Since we use only one field, Interlace = 0 (both fields are stored in
separate memories; in addition for our example the odd image is
obsolete).
We select the single-shot mode, since only one image should be
digitized and not a continuous series.
Now digitization can be started, which is done by invoking the
function Start_Grabber(1). During the following while-loop the pro-
gram waits, until the digitized field will be stored completely in the
memory. For this reason we call the function Data_Present() for
Grabber #1. The returnvalue will be concatenate with 0x04 AND, in
order to mask the third bit (bit # 2). This is the S_EVEN-bit
(see Figure 49). This bit will be set, after the even image is stored
completely in the memory. Since only this information is interesting
to us, the other status bits are masked out. The delay time in the loop
prevents, that the status is permanently inquired, which might be
disturbing for the data transfer on the PCI-Bus.
After the end of the digitization, the instruction Stop_Grabber() has
to be given, so that the Grabber is set to the none operative status.
Otherwise the Grabber remains in the standby position and no further
digitization can take place.
The image is now found in the defined array and can be evaluated. In
order to repeat recording of a new image with the same dimensions
from the same channel, the program can call again the function
Start_Grabber().