4-4
Root Level Commands
AUToscale
This command causes the analyzer to evaluate the current input signal and find the optimum
conditions for displaying the signal. It adjusts the vertical gain and offset for the channel, and
sets the time base on the lowest numbered input channel that has a signal. If signals cannot
be found on any vertical input, the analyzer is returned to its former state.
Autoscale sets the following:
• Channel Display, Scale, and Offset
• Trigger and Level
• Time Base Scale and Position
Autoscale turns off the following:
• Measurements on sources that are turned off
• Functions
•Windows
• Memories
No other controls are affected by Autoscale.
For faster and more reliable execution of the autoscale function, enter the signal’s data rate
using the optional <data rate> argument. The instrument uses this argument as an aid in set-
ting the horizontal scaling for a signal. The value is only valid for NRZ eye diagrams or clock
signals. The <data rate> argument sets the data rate in the same manner as the TRIG-
ger:BRATe and TIMebase:BRATe commands. The limits for all three commands are identical.
Normally, the valid range is 1 Mb/s to 160 Gb/s, however, in pattern lock, the range is 50 Mb/s
to 160 Gb/s. When using the 86107A precision timebase, the data rate must be a multiple of
the reference clock frequency. Refer to “PRECision:RFRequency” on page 23-3.
Example This example sets the data rate to 155.520 Mb/s and automatically scales the analyzer for the
input signal.
10 OUTPUT 707;":AUTOSCALE 155.520E6"
Query :AUToscale?
Returns a string explaining the results of the last autoscale. The string is empty if the last
autoscale completed successfully. The returned string stays the same until the next autoscale
is executed.
The following are examples of strings returned by the AUToscale? query.
No channels turned on
Left module requires calibration for autoscale
Right module requires calibration for autoscale
Channel n signal is too small
Channel n signal is too high
Channel n signal exceeds the measurable range at the top
Channel n offset exceeds the measurable range at the bottom
No trigger or trigger too slow
Trigger is in Free Run