After you create an instrument , you can log changes of its value through time with the Log
instrument values option from Instruments and markers menu.
After you choose Log instrument values option... option from the Signal tools menu, you will have
to determine the length of the log signal (in samples). A new, empty, signal of the defined length
will be created and a new window will appear.
Each time the instrument's value changes, it will be added to the log window - it will work just as
old-fashioned paper-tape recorder.
Scrolling and resetting
Log window will monitor all changes in the instrument and add all consecutive values from
instrument into one signal. When this signal reaches maximum length you determined, the
display will start to scroll, removing oldest values and adding new ones. By choosing Reset data
from the Log window’s context menu (or pressing F3), you can clear
all value and start logging
again. By using Start/Stop options from the context menu, you can stop logging and start it again.
Value log signal will try to determine values for its X-axis automatically by backtracking through
the analysis chain to the root signal window. If those X values are equidistant (i.e. difference
between two consecutive values is always the same), those will be display on X-axis of the
instrument log. If not, X-axis will switch to unit called "change" where each new value will simply
be labeled with its index, i.e. 0,1,2,3,4,...
Long-time logging of instrument values in a file
Since instrument log keeps its data in your computer's RAM, total storage length is very limited.
For long-time recording of signal values, you can use Logging data to file
option connected to a
log instrument window. For example, this would be a Control Window display of a system to store
max. frequency from an FFT into a file.
Instrument log in this system stores only a last 100 values and can be used for monitoring. File
log window, on the other hand, stores all values which are added to a instrument log into a file.