Stripchart
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The Data Item format Stripchart displays a data item as a strip chart, that is the data value is displayed over time. The following picture illustrates a typical Stripchart display:

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The Stripchart format can display up to five graphs. If you select an array item and choose to display five or more elements the first five elements will be charted in the color specified with the color dialog.

The Data Item format dialog box for Stripchart displays looks as follows:

dataitemformatstripchartdialog

The scroll width determines how much of the x-range is displayed at least at any given time. Say you specify 50%, the display will scroll back 50% as soon as it reaches the end of the display. Scroll width 0% equals smooth scrolling but incurs the most overhead. If you have very fast updating data items you might want to at least allow for about 25% scroll width to keep the data update efficient. Every time the display needs to be scrolled the entire display needs to be rendered, whereas if no scrolling is necessary only the according data line needs to be drawn. So the faster the update rate is the smaller you want to set the scroll width.
As with other graphical displays the Orientation dialog allows you to configure different orientations. The most appropriate for a Stripchart display is probably the 1-L orientation displayed above where the origin is in the lower left corner. The picture below shows the same display with right hand orientation.


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The check boxes for the x- and y-Grid let you turn on/off the respective grid. To make the display range visible a scale object can be attached to a Stripchart. This will result in a display similar to the one below.

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Update Properties
The Stripchart display offers additional update properties. The following image shows the Stripchart Update Properties sheet.

dataitemformatstripchartupdatedialog

A major different of the Stripchart display compared to other display formats is that the Stripchart keeps state. So it is important how often we sample the data to get an accurate display. The sample mode offers two settings: Block-Arrival and Timer based.

There are basically two scenarios that we use a stripchart for: To monitor an item that is periodic and updates reqularly and we know the time constant of the update period. In that case we would use the Block-Arrival mode. We can enter the time base in the edit field in the Sample Settings group.
This way you will get a correct time base. The x-dimension of the Range determines the time interval that is displayed. Say you specify Block Arrival and your period is 2s and that's what you specify in the 'Sample data every' field. If you select a x-Range of 0 .. 200, you will see 100 data points on the display which equals 200s. The x-range is specified in seconds.
The y-range determines the mapping of the values to be displayed. By default the y-range is 0 .. 1, so you most likely have to adjust it to fit your data accordingly.

If you don't have a periodically updating item or you want to display an item over clock-time you would use the Timer based sampling and enter the sample time in the time base edit field. Say you set the sample time to 3s, this would result in sampling the data source every 3 seconds.

The settings above determine how often the data source gets sampled. This doesn't have to coincide with the update of the display. The Display Settings group allows you to configure the update rate. Since updates of the Stripchart can potentially be very expensive you can configure the sample timing and the update timing separately. Say you want to use the Block-Arrival sampling and your data item arrives with a 1KHz frequency you might want to decide to use a timer based display update of 200ms. In that case you would choose Timer for the display update and 0.2 for the update period. You have the option of updating the stripchart with every sample if you choose Sample mode.

The stale settings are the same as for all other items.