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| Home > Configuring the ETM > Configuring the ETM parameters > Cycle accurate tracing | |||
This setting determines whether the ETM operates in cycle-accurate mode:
When Cycle accurate tracing is selected, the ETM records the number of cycles executed while tracing is enabled. This includes cycles during which no trace information is normally returned, such as memory wait states.
The Elem column of the Analysis window
shows the cycle number of the cycle in which each instruction was
executed. The count does not include cycles executed during a trace discontinuity.
You must use the Time/ column,
which displays timestamp values, to measure across discontinuities
in the trace output.unit
If Cycle accurate tracing is not selected, the ETM does not record cycle counts.
Be aware of the following for cycle-accurate tracing:
For ETMv3, timestamping and cycle-accurate tracing are mutually exclusive.
For ETMv1, cycle-accurate tracing does not record timing information between trace discontinuities.
Fewer instructions are captured when doing cycle-accurate tracing relative to non cycle-accurate tracing. This is because the ETM must output more information with less compression.