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CHAPTER 2 DEPENDENCE FUNCTIONS
Figure 2.5-2 Frame Number at Tracing
■ Trace Filter
To make effective use of the limited trace buffer capacity, in addition to the code fetch function, a trace filter
function is incorporated to provide a means of acquiring information about data accesses to a specific region.
The following value can be specified in the data trace filter function.
• Access attribute (read/write)
• Data trace start address/end address
Moreover, the function to compress into one frame when the same frame is repeated is provided, too.
■ Trace Trigger Setup
When preselected conditions are met during MCU bus operation monitoring, a trigger for starting a trace can
be generated. This function is called a trace trigger.
For the use of the trace trigger function, specify the code (/CODE) and data access (/READ/WRITE).
Up to 4 trace triggers can be preset each for code attribute and data access attribute. However, actually, the
maximum number of trace triggers is determined as indicated below because the common hardware is used
with events.
Current trace trigger maximum constant = 4 - (current break count setting + current event count setting)
For the trace trigger setup conditions that can be defined, see Table 2.5-2.
For trace trigger setup, use the following commands:
• SET TRACETRIGGER : Sets trace trigger
• CANCEL TRACETRIGGER : Deletes trace trigger
• SHOW TRACETRIGGER : Displays trace trigger setting status
• SHOW TRACE/STATUS : Displays Trace setup status
Figure 2.5-3 shows a trace sampling operation.
Figure 2.5-3 Trace Sampling Operation (Trace Trigger)
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-3
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-1
0 (Trigger point)
Suspend Resume
Program flow
Trace buffler
Start
Suspend
Resume
Resume
Suspend