Gathering Data
LabHelper's screen display during data acquisition varies with
operational mode and the number of channels. Users can vary the colors
of the screen stripcharts (from the screen
colors option of the 'VIEW' menu).
The following discussion refers to the built-in "standard"
colors specified in the standard 'LabHelper prefs' file, and may not
be the ones the user prefers.
In CHART mode (shown above), the plot areas (1 to
a maximum of 16) are dark gray, with pale blue grid lines and lettering.
Data are plotted as yellow lines extending left to right across the screen.
The information shown in the plot areas and the data bar varies with sampling
rate. At high sampling rates, the data bar at the top of the screen,
just below the menu bar, shows only the sample number and the maximum number
of cases. At slower sampling rates, the data bar shows the sample
number, the time, the percent completion, the time to go, and the maximum
number of cases. If Autorepeat is selected, a small window in the
first channel's plot area shows the current file name under which data will
be stored. Except at high sampling rates, channel values (the last
value recorded for each channel) appear in the plot area(s); this is under
user control. At the bottom of the plot area are tics showing an elapsed
time scale. If one of the external device control modes is operating,
a yellow-on-blue legend reading " '-' for ref, '+' for sample "
appears in the lower part of the screen below the plot areas. In this
example:
If -- as in this example -- you are using a 'compressed' view mode (selected with the chart view button on the Display Setup window), the degree of view compression is shown in the lower left of the screen, together with a graphical index. If you are using a combination of maximum number of samples and view compression that will require more than one screen to complete, a graphical representation of the screen in use appears in the upper right. The 'in-use' screen is in green, previous screens are in black, and 'future' screens are in outline.
If your screen is wider than 640 pixels, a small yellow window showing the backup status appears in the lower right corner (not shown here).
Markers (to indicate important events, timing, or other uses) are entered by hitting any letter or number key; they appear as vertical lines on the plot areas. Markers are stored in the data file and can be displayed during data analysis. To enter the Options window (for saving data and other operations), hit the ESC key.
In OSCILLOSCOPE mode, the single plot area is dark
blue, with pale blue grid lines and white lettering. Data points are
in yellow. The data bar shows only the maximum number of points on
the screen. A small window in the plot area shows the file name and
suffix under which the next screenfull of data will be stored. At
the bottom of the screen are instructions for saving screens of data (hit
the TAB key), or exiting to the Options
window (hit the ESC key; see below). At the bottom of the plot area
are tics showing an elapsed time scale. Markers are not allowed in
Oscilloscope mode.
In OSCILLOSCOPE PLUS CHART mode, the topmost plot
area functions like the regular Oscilloscope mode, with dark blue plot area,
pale blue grid lines, white lettering, and erasable yellow data points.
During intermittent sampling, the plot area for scope data is red, not blue.
The plot areas for chart channels are the 'usual' dark gray, with light
blue grid lines and lettering, and yellow data lines. The data bar
shows the trace length of the chart screen, and at slow oscilloscope sampling
rates it also shows the number of points recorded on the chart channels.
A small window in the plot area for the scope channel shows the file name
under which the next screenfull of data will be stored. Channel values
do not appear, and markers appear only in the plot areas for chart channels.
Markers can be entered by hitting any letter or number key, or they can
be entered automatically by the computer when oscilloscope screens are saved.
Automatic markers are a sequence of numbers running from 0 to 9, with the
sequence repeating up to a total of 64a markers. You can still enter
markers manually by hitting any letter or number key.
The view compression and screen indicators are as described for chart mode, above.
To store the currently-displayed oscilloscope screen, hit the TAB key. To enter the Options window (for saving the chart channels and for other operations), hit ESC. At the bottom of the plot area are tics showing an elapsed time scale.
In MULTICHANNEL OSCILLOSCOPE mode, the plot area
is red, with yellow grid lines and lettering on each of the 2 -4 channels.
Data points are yellow. The data bar shows only the maximum number
of points on the screen and the tracelength. A small window in the
first channel's plot area shows the file name and suffix under which the
next screenfull of data will be stored. At the bottom of the screen
are instructions for saving screens of data (hit the TAB key), or exiting
to the Options window (hit the ESC key;
see below). At the bottom of the plot area are tics showing an elapsed
time scale. Markers are not allowed in Multichannel Oscilloscope mode.
At low sample rates (and hence long sample periods), the response of the computer to keyboard commands is greatly slowed. This is because the computer only checks for keyboard input between screenfulls of data, not when actually recording.