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Default Trace Specification
The default trigger condition is "never". You can make a default trace
measurement by entering the Trace Again command. When you use the
default trace condition, qualified bus cycles are collected continuously until
you halt the measurement. The trace buffer will then contain the bus states
prior to the halt.
Trace Events
Trace measurement parameters are specified as events. An event is a bus state
consisting of a combination of address, data, and status values.
Address and Data Values. Address and data values may be specified as
32-bit values or a range of of 32-bit values. You can specify a mask to mark
valid bits in addresses or data to define "don't care" values. You can also
specify the logical "NOT" of an address or data value.
Status Values. Status values are the types of bus activities, such as:
Read or write operations.
Memory access size.
Function codes.
Cycle types.
You can also specify the logical "NOT" of a status value.
Trace Trigger
A trigger specifies the bus events that cause the debugger to make a trace
measurement. The debugger lets you trigger on the detection of a single
event, an OR'ed combination of events, or after a sequence of events are
detected. You can specify a sequence of events, the last of which is the
triggering event. You can also trigger on the Nth occurrence of an event,
where N is a number you specify with the count parameter in the Trace
Trigger Event command.
You can position the trigger event at the start of the trace buffer, centered in
the trace buffer, or at the end of the trace buffer.
Chapter 6: Making Trace Measurements
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