Campbell Scientific RTDM Real-Time Data Monitoring Software - Manual (Page 17)

RTDM Version 2.1 – Real Time Data Monitor
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4.2 Real Time Scrolling
In normal real-time (or pseudo real-time) operation the charts will continuously
move, or scroll, from right to left as new data is displayed. Whenever any
display manipulation is carried out, as explained above, the scrolling will
pause, and a clock icon will appear in the top right corner of the display. To
resume real-time scrolling, click on this icon.
4.2.1 Tabbed Notebook Display
The Tabbed Notebook component allows a display to be split onto a number of
different pages. These pages can be made to turn from one page to the next
automatically, with a pre-defined delay between pages, like flicking through a
book. This produces a continuously changing display, which can be useful for
‘hands-off’ automatic presentations, etc. See the on-line help system for more
details of the Tabbed Notebook and associated Pages.
4.3 Controlling the Display (Auto Continue)
Although this paragraph contains some advanced topics, it is an important part
of run time control, and is worth a brief mention here. As always, further
details can be found in the on-line help system.
When your design includes scrolling charts or tabbed notebooks, the user can
manually pause and restart the displays as indicated above (see Real Time
Scrolling). However, the designer may have built in a function to restart the
display automatically after a given time (this function is called Auto Continue,
and more details can be found in the on-line help system). This function guards
against a display being inadvertently paused for a long period, perhaps causing
the user to be unaware of an important event or an alarm condition for some
time.
When Auto Continue is active, if a display has been paused for any reason,
when the maximum delay time (specified by the display designer at design
time) is reached, the clock face icon will start to flash for a few seconds, and
then scrolling will restart. To prevent scrolling re-starting automatically, the
user must reperform the manual operation that originally caused the scrolling
to stop (for example, using zoom on a chart). If Auto Continue is not enabled,
the user can start and stop scrolling manually as discussed above, bearing in
mind that he may be unaware of any alarm or other important conditions while
scrolling is paused.
4.4 Incorporating RTDM Charts into World Wide Web Pages
(SnapshotSet)
RTDM has the capability to automatically save JPEG (*.jpg), GIF (*.gif),
Bitmap (*.bmp) or Portable Network Graphics (*.png) files created from
portions of a form. These images can be from many sources, including a
webcam, so providing constantly updated information for output to a web page.
The definitions are set up using SnapshotSet (see on-line help for full
description).
To see a typical application of output from RTDM to the Internet, see the
Campbell Scientific web site (www.campbellsci.co.uk) and check the ‘Live
Weather Data on the Web’ demonstration.