Specifications

Chapter 3 51
Setting Measurement Conditions
Set Display Scale
3. Setting Measurement Conditions
Set Display Scale
When the measurement screen is set to display a graph, the display scale for the specified
trace can be set automatically to the most appropriate value or can be set manually to a
desired value.
Select Trace for Which Scale Is Set
If both data and memory traces are displayed on the screen, use the following GPIB
command to select the trace (data trace, memory trace, or both traces) for which the scale is
to be set.
• DISP:TRAC{1-5}:Y:FOR on page 366
Automatic Scale Adjustment
When a trace goes out of the scale range, use the following GPIB command to adjust the
scale automatically so that the trace stays within the scale range.
• DISP:TRAC{1-5}:Y:AUTO on page 364
• DISP:TRAC:Y:AUTO:ALL on page 364
Manual Setting of Scale
In addition to automatic scale adjustment, the E4991A provides a way to manually set the
scale values. As shown in
Figure 3-2, scale parameters depend on the display format of a
trace.
Linear Y-Axis Format
The display scale can be set in two ways: by using full-scale and reference values or by
using maximum and minimum values. Use the following GPIB commands to set the scale
parameters.
Display format Parameter to be set GPIB command
Linear Y-axis format
(Using max and min
values)
Maximum value DISP:TRAC{1-3}:Y:TOP on page 372
Minimum value DISP:TRAC{1-3}:Y:BOTT on page 365
Reference line’s position DISP:TRAC{1-3}:Y:RPOS on page 370
Linear Y-axis format
(Using full-scale)
Full-scale value DISP:TRAC{1-5}:Y:FULL on page 367
Reference line’s value DISP:TRAC{1-5}:Y:RLEV on page 369
Reference line’s position DISP:TRAC{1-3}:Y:RPOS on page 370