
Capture Sources and Destinations
Figure 77 shows a block diagram of the Capture object
CaptureEnable
1 | 3 |
CaptureActivate
CaptureEnable
CaptureActivate
CaptureReset
Time
Command Position
Feedback Position
Master Position
Captured Data
CaptureTriggered
2
CaptureTriggered
CaptureReset
Figure 78: Capture Timing Diagram
Figure 78 is a timing diagram that shows how the different capture related sources and destinations function. The
Figure 77: Capture Object
Sources
CaptureTriggered - The CaptureTriggered signal is
Destinations
CaptureEnable - The CaptureEnable is used to enable or "arm" the capture component. If the CaptureEnable is not active, then the CaptureActivate has no effect, and the CaptureTriggered remains inactive. Once the CaptureEnable is activated, the Capture component is ready and waiting for a CaptureActivate signal to capture data. CaptureEnable is a
CaptureActivate - If the Capture component is enable and has been reset (CaptureTriggered is inactive), then the rising edge of CaptureActivate will capture the four data parameters and cause CaptureTriggered to be activated. If the Capture component is not enabled, or has not been reset, the CaptureActivate will be ignored.
CaptureReset - The CaptureReset is used to reset or
Once the capture has been activated, the CaptureTriggered destination will be active. The capture component cannot capture data again until it has been reset. The capture component will automatically reset itself if the CaptureEnable signal is removed.
three numbers located on the diagram are associated to the following three notes respectively:
1.While CaptureTriggered is active, a rising edge on CaptureActivate will be ignored. The capture object can not activate again until it has been reset.
2.When CaptureEnable is deactivated, CaptureTriggered automatically deactivates because the capture object is automatically reset. The captured data is retained until the capture component is
3.CaptureActivate has no effect while the capture component is not enabled.
Sources That Can Accurately Capture Data
Only a select few sources can accurately capture data. The reason that only certain signals can accurately capture data is because they are wired directly to the
Sources that CAN accurately capture data:
•
•Motor Encoder Marker Channel
•Index.#.CommandComplete
•Jog.#.CommandComplete
•Index.#.AtVelocity
•Jog.0.AtVelocity
•PLS.#.Status
All other Sources are only accurate to the Trajectory Update Rate.
Assignments that Automatically Use Position Capture
The sources listed above automatically capture data each
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