BitFlow Cyton-CXP, Справочник по аппаратуре

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The StreamSync Acquisition Engine World The Cyton-CXP
CYT-2-4 BitFlow, Inc. Version A.0
met) or it can just be opened immediately, as soon the Acquisition Engine level is
inside the X window (i.e. the stat above). Table 2-1 enumerates all of these condi-
tions..
2.2.2 Observing the StreamSync Acquisition Engine
The state of the Acquisition Engine can be observed at any time. The register AE_
LEVEL indicates the current run level of the Acquisition Engine. In other words, this
register returns the current state as shown in Figure 2-2. While this is not very useful in
a free-running situation, as the value will be changing constantly, it can be very helpful
debugging if the system gets stuck (e.g. waiting for a trigger).
2.2.3 Synchronizing the StreamSync Acquisition Engine With the Camera
Normally acquisition is synchronized with camera by special CXP header packets
called Start Of Frame (SOF) and Start Of Line (SOL). The Acquisition Engine will syn-
chronize its Y window (frame) with the SOF and X window with the SOL. This means
that all packets from the camera will be dropped until the SOF is seen (causing the
Acquisition Engine to open the Y window), and then packets are further dropped until
SOL must be seen (opening the X window). Each line requires an SOL packet. This
process keeps the Acquisition Engine synchronize to the camera even if packets are
dropped. This functionality can be enable/disable by the ZSYNC and YSYNC bitfields.
2.2.4 Regions Of Interest (ROI) with the StreamSync Acquisition Engine.
The Acquisition Engine support capturing a subwindow or ROI of the image that the
camera is putting out. The Y_SIZE and X_SIZE registers control how many lines and
pixels are acquired per frame, regardless of the actual frames size coming out of the
camera. Further there are Y_OFFS and X_OFFS registers which can locate the subwin-
dow anywhere inside of the camera’s frame. These concepts are show in Figure 2-3.
Table 2-1 Open Close Conditions
Window Open Close
V AE run level set to Run Abort V, V_SIZE ZWindows
Z Trigger, Immediate Trigger, Abort Z, Z_SIZE Y
Windows
Y Trigger, SOF, Immediate Trigger, Abort Y, Y_SIZE X
Windows
X SOL, Immediate Abort X, X_SIZE pixels