Xilinx ChipScope Pro, Руководство пользователя

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68 www.xilinx.com ChipScope Pro Software and Cores User Guide
UG029 (v14.3) October 16, 2012
Chapter 4: Using the ChipScope Pro Analyzer
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If occurring in at least n clock cycles is selected, then n contiguous or n noncontiguous
events satisfies the match function counter condition, and it remains satisfied until the
overall trigger condition is met.
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If occurring for at least n consecutive cycles is selected, then n contiguous events
satisfies the match function counter condition, it remains satisfied until the overall
trigger condition is met or the match function value is no longer satisfied.
Note:
When the overall trigger condition consists of at least one match unit function that has a
counter set to either Occurring in at least n cycles or Lasting for at least n consecutive cycles ,
the Window Depth or Samples Per Trigger setting cannot be less than eight samples. This is due to
the pipelined nature of the trigger logic inside the ILA core.
Trigger Conditions
A trigger condition is a Boolean equation or sequence of one or more match functions. The
core captures data based on the trigger condition. More than one trigger condition can be
defined. To add a new trigger condition, click the
Add button. To delete a trigger condition,
highlight any cell in the row and click Del . Although many trigger conditions can be
defined for a single core, only one trigger condition can be chosen (active) at any one time.
Active
The Active field is a radio button that indicates which trigger condition is the currently
active one.
Trigger Condition Name Field
The Trigger Condition Name field provides a mnemonic for a particular trigger condition.
Trigger Condition
n is used by default.
Trigger Condition Equation
The Condition Equation field displays the current Boolean equation or state sequence of
match functions that make up the overall trigger condition. By default, a logical AND of all
the match functions present (one match function for each match unit) is the trigger
condition. To change the trigger condition, click the
Condition Equation field, which
brings up the Trigger Condition dialog box.
Trigger Condition Editor Dialog Box
If a trigger sequencer is present in the core, the Trigger Condition dialog box has two tabs:
Boolean and Sequencer . When the Boolean tab is active, the trigger condition is a Boolean
equation of the available match units. When the Sequencer tab is active, the trigger
condition is a state machine, where each state transition is triggered by a match function
being satisfied.
The Boolean tab of the Trigger Condition dialog box has a table of all the match units.
Each match unit occupies a row in the table. The Enable column indicates if that match
unit is part of the trigger condition. The Negate column indicates whether or not that
match unit is individually negated (Boolean NOT) in the trigger condition.
All the enabled match units can be combined in a Boolean AND or OR operation,
selectable using the radio buttons above the match unit table. The overall equation can also
be negated, selectable using the
Negate Whole Equation checkbox above the table. The
resulting equation appears in the Trigger Condition Equation pane at the bottom of the
window.