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Scope variables report operating parameters and capture statistics
Scope variables report measurement values and are shown below the main display:
The set of variables shown depend on the display type and whether features such as cursors are enabled. In this screenshot, the variables are the defaults that are shown upon DSO power on.
Variables are identified by a two character name and are typically colour coded on the display:
|TB||Timebase||Time per division (Graticule Enabled) or time per display (Graticule Disabled).|
|BW||Bandwidth||Spectrum display bandwidth or Nyquist frequency (aka the highest displayed frequency).|
|FS||Sample Rate||Display or capture sample rate. The rate reported depends on the data mode (i.e., it reports the effective sample rate of the waveform).|
|TD||Time Delay||Pre/Post-trigger time delay (non-zero if pre-trigger, delay or time offset has been set).|
|VA||Voltage Scale||Volts per division (Graticule Enabled) or Volts per display (Graticule Disabled) for Channel A. Other channels (VB, VC and VD) similar.|
|VM||Voltage (Mark)||Voltage at the Mark Cursor on the selected channel.|
|VP||Voltage (Point)||Voltage at the Point Cursor relative to the Mark. Reported in the colour of the selected channel (eg, Yellow for CH A).|
|TM||Time (Mark)||The time offset from the trigger point to the time mark cursor.|
|TP||Time (Point)||The time difference between the two time cursors.|
|FM||Frequency (Mark)||The value of the Mark frequency cursor. Appears in spectrum displays only.|
|FP||Frequency (Point)||The difference (aka bandwidth) between the Point frequency cursor and the Mark frequency cursor. Appears in spectrum displays only.|
|MM||Magnitude (Mark)||The value of the Mark level cursor (in dB). Appears in spectrum displays only.|
|MP||Magnitude (Point)||The difference between the Magnitude Point and Mark cursors. Appears in spectrum displays only.|
An important distinction between these variables and parameters that control them is that the variables are always associated with a waveform, spectrum or logic currently displayed.
This is in contrast to some parameters (eg, timebase) which may be changed to new values which do not correspond to the displayed waveforms until a new capture is performed.