Trigger

The Trigger Conditions panel may be accessed in either of two ways:

Click on the Pane / Trigger menu item.
Click on the Trigger button.

Trigger includes menu options for beginning and ending signal data acquisition, such as by manually clicking on the Go and Stop buttons, or through the use of external inputs such as motor movement.

The Trigger Conditions panel is divided into four different sections, each of which is described below, along with their respective menu items.

Start Condition

Start Condition defines the triggering event used to start signal data acquisition. This may be either user-triggered, or activated automatically using an outside condition.

Go button-- Traces are started when the Go button is clicked on the front of the display pane. Selecting this option displays two support buttons on the front of the display pane:

Go-- Tracing begins immediately after the Go button is clicked.
Stop-- Tracing is halted when the Stop button is clicked.

Motion Start-- Tracing begins when movement is detected in the Motion Supervisor chosen for tracing after the Arm button is clicked on the display pane. Selecting this option displays two support buttons on the front of the display pane:

Arm-- The Arm button is displayed on the display pane whenever Motion Start is selected. Tracing does not begin until the Arm button has been clicked; tracing ends according to the condition set in the "End Condition" box of the Trigger Conditions panel (see below).
Repeat-- The Repeat button is used to continue data acquisition beyond a single pane, after the Arm button has been clicked. The previous move data will be overwritten and the new move data will be displayed.

External Event-- (Not yet implemented.)

Pre-Trigger (ms)-- [Usable only when Motion Start enabled.] Amount of data to include with plot before triggered data.1

End Condition

The End Condition defines how tracing is to be halted.

Stop button-- Tracing ends when the Stop button is clicked on the main display panel.

Buffer Full-- Tracing ends when the data buffer has filled. NOTE: the data buffer size is set by the MaxBuffer field on the main display pane and may be as large as 50000 ms.

Motion Done-- Tracing ends when motion halts (i.e., when MotionDone condition is TRUE).

External Event-- (Not yet implemented in Version 1.19.07.)

If either the Start Condition or End Condition fields are set to Motion Start or Motion End respectively, the Trigger Source field will be enabled. This field specifies which Motion Supervisor is used to trigger start and/or end of tracing.

Trigger detection may be implemented either by monitoring changes to motion status in the data stream (Status Data Stream), or by polling the controller for status (Status Poll). Note that changes to the motion status can be extremely fast, and may go undetected. Under most conditions, selection of the Status Data Stream menu item is recommended.

1. Acquisition of data is ongoing, even before the start of tracing. When a Pre-trigger time is entered, the display will include buffered data of Pre-trigger length with the triggered trace.