Chapter 6
Historical Data Logging and Extraction
©
National Instruments Corporation
6-11
Panning Buttons
The Panning buttons allow you to move backward and forward through the
historical data in the trend. The buttons do not affect the timespan of the
trend. For example, if the trend displays data from 9:45 to 9:55 on the same
day, the timespan is ten minutes. Table 6-2 describes the Panning button
functions.
Manual Changes
You can also select the text at either end of the time axis and change the
data. You must enter the date in the correct format. If you make an error,
the input is ignored.
You can select and enter the time and date on the time (X) axis of the
historical trend on the HTV directly. However, the HTV responds
immediately to any changes you make. If you want to make manual edits to
both the start and stop time on the time axis, you can select the
Viewer»Time & Date option. When you select this option, a dialog box
appears, shown below, and you can enter the start and stop time of the data
displayed in the trend.
Table 6-2.
Panning Button Functions
Button
Name
Description
|<
Retrieve oldest data
Displays the first available page of data.
<<
Back to closest point
Centers the display around the closest point to the left
of the timespan. If there is no data in the previous time span,
skips to the previous end of data.
<
Back one-half page
Moves the display back by half of the current timespan.
>
Forward one-half page
Moves the display forward by half of the current timespan.
>>
Forward to closest point
Centers the display around the closest point to the right
of the timespan. If there is no data in the next time span, it
skips to the next start of data.
>|
Most recent data
Displays the most recent available page of data.
