Teledyne HDO9000, Руководство оператора

Страница: 72 / 188

HDO9000 High Definition Oscilloscopes Operator's Manual
Conditions (Smart Triggers)
Smart triggers all allow you to apply Boolean logic to refine the triggering condition beyond simply
Level and Slope/Polarity.
The values that satisfy the operators of Less Than , Less Than or Equal To , Greater Than , etc. can be
set by entering an Upper Value and/or Lower Value .
In some cases, it is possible to set a range of values that satisfy the condition. The values may be In
Range that is bounded by the upper/lower values or Out Range .
The extent of the range can often also be specified by using a Nominal and Delta value, rather than an
absolute upper and lower value. In this case, the Nominal value sets the center of the range, and the
Delta determines how many units plus/minus the Nominal value are included in the range.
Patterns
A triggering pattern of low/high states across multiple inputs is used by the Pattern type and
MultiStage types that include Patterns as either the arming or triggering event. Patterns may be set
on analog channels, digital lines, or a combination or both when Mixed-Signal capabilities are
available.
Digital Pattern
The Logic Bus method simplifies pattern set up by utilizing digital groups and logic you have already
defined on the Digital Setup dialogs. A digital pattern is set on a single bus (group) manually or by
applying a hexadecimal value, while the remaining lines are disabled ("Don't Care").
If you have not set up digital groups, you can set a digital pattern line by line using the Logic method.
All available lines remain active for selection.
1. On the Trigger dialog, select Pattern trigger type. Open the Digital Pattern dialog.
2. At the far right of the dialog, choose either Logic Bus or Logic .
3. Optionally, deselect Filter Out Unstable Conditions . This default filter ignores short glitches in
logic state triggers that last less than 3.5 ns.
4. If using Logic Bus, touch Source and select the digital group. Any lines that are not in this
group will now be disabled.
5. To apply a digital logic pattern, either:
l
Enter the hexadecimal value of the pattern in Hex or Value . Lines will take a logical 1, 0,
or X ("Don't Care") according to the pattern. Disabled lines will remain X.
62