advertisement
CVI/CCF File Parameters Used
Shaft Encoder Enable = X, where:
• If X = 1, Shaft Encoder is enabled
• If X = 0, Shaft Encoder is disabled
Shaft Encoder Pulse Drop = X, where:
• X = number of trigger pulses ignored between valid triggers
For information on camera configuration files see the Sapera Acquisition Parameters Reference Manual
(OC-SAPM-APR00).
Virtual Frame Trigger for Linescan Cameras
When using linescan cameras a frame buffer is allocated in host system memory to store captured video lines. To control when a video line is stored as the first line in this “virtual” frame buffer, an external frame trigger signal is used. The number of lines sequentially grabbed and stored in the virtual frame buffer is controlled by the Sapera vertical cropping parameter.
Virtual Frame Trigger Timing Diagram
The following timing diagram shows an example of grabbing 10 video lines from a linescan camera and the use of virtual frame trigger to define when a video line is stored at the beginning of the virtual frame buffer. The virtual frame trigger signal (generated by some external event) is input on the X64-CL iPro trigger input.
• Virtual frame trigger can be TTL 5V or LVDS and be rising or falling edge active, active high or low, or double pulse rising or falling edge.
• Virtual frame trigger control is configured for rising edge trigger in this example.
• Virtual frame trigger connects to the X64-CL iPro via the External Trigger Input 1 & 2 balanced inputs on connector J4, Input 1: pin 11 (+) and 12 (-), Input 2: pin 13 (+) and 14 (-).
• After the X64-CL iPro receives virtual frame trigger, the camera control signal is output to the camera to trigger n lines of video as per the defined virtual frame size.
• The camera control signal is either based on timing controls input on one or both X64-CL iPro
shaft encoder inputs (see “J4: External Signals Connector ” on page 95 pinout) or an internal
X64-CL iPro clock.
• The number of lines captured is specified by the Sapera vertical cropping parameter.
62 • X64-CL iPro Reference
X64-CL iPro Series User's Manual
Synchronization Signals for a Virtual Frame of 10 Lines.
The following timing diagram shows the relationship between external Frame Trigger input, external
Shaft Encoder input (one phase used), and camera control output to the camera.
Virtual Frame
Trigger
In
Shaft Encoder
In
EXSYNC
Out
LVAL
In
Video Line
In
Note: In this example, 10 lines are acquired
The Maximum frame rate = Max. Line Rate / nb lines (Hz)
In / Out signal reference is relative to frame grabber
CCF File Parameters Used
The parameters listed below provide the control functionality for virtual frame reset. Applications either load pre-configured .CCF files or change these parameters directly during runtime.
Note that camera file parameters are best modified by using the Sapera CamExpert program.
External Frame Trigger Enable = X, where:
• If X = 1, External Frame Trigger is enabled
• If X = 0, External Frame Trigger is disabled
\\Virtual Frame Trigger enabled
External Frame Trigger Detection = Y, where:
• If Y= 1, External Frame Trigger is active low
• If Y= 2, External Frame Trigger is active high
\\ with Virtual Frame Trigger edge select
• If Y= 4, External Frame Trigger is active on rising edge
• If Y= 8, External Frame Trigger is active on falling edge
• If Y= 32, External Frame Trigger is dual-input rising edge
• If Y= 64, External Frame Trigger is dual-input falling edge
External Frame Trigger Level = Z, where:
\\ with Virtual Frame Trigger signal type
• If Z= 2, External Frame Trigger is a RS-422/LVDS signal
X64-CL iPro Series User's Manual
X64-CL iPro Reference • 63
advertisement