Trace Use Cases

Trace Use Cases

• Use with CCS during development to debug difficult problems

- Either on-chip ETB or external trace data export (to an XDS560T) can be used to capture trace data for debug

- Understand and characterize the problem first. See Trace's Place in the Debug Tool Box for more discussion on why this is important.

- Understanding the Trace System's limitations before using the tool.

* The trace system does not have the bandwidth to provide visibility to all streams (PC, Timing and Data) at the same time

- Triggers must be setup to get visibility to the problem.

* Your problem may require start triggers (start trace near the problem), end triggers (trace up to the problem) or both to create windows of visibility.

* An End All Trace job will terminate all started trigger jobs, causing all trace export to be terminated, trace data recoding stopped and the trace display (DVT) updated with the new trace data. When combined with a circular buffer (ETB or XDS560T) this is an excellent method to preserve the trace data you need for visibility to the issue.

- What to trace once you trigger

* Do you need visibility to just the PC, PC and Timing, CPU memory accesses or Events?

* Do you need visibility to some streams only part of the time

- What search criteria will you use once you have captured the data

• Use with CCS during development to profile your application (For instructions see CCS Help->Tasks->Using Trace Analyzer)

- Function level cycle, stall, per-call profiling provided.

- For Function cycle and stall profiling a simple Trace On job with PC and timing data selected required.

- On-chip ETBs are typically not deep enough to provide satisfactory results while profiling

(Note- if you require more than a second of execution time to profile your application you may want to consider using statistical profiling)

• Use CCS with scripts during development to do statistical or complex profiling of your application

- CCS only used to setup trace triggers and enable data acquisition

- Scripts used to process data

- cToolsLib Debug Libraries, specifically AETLib can be utilized to setup Trace Jobs for profiling from your application

• Use with cToolsLib Debug Libraries and ETB (Embedded Trace Buffer) to provide field visibility to unexpected activity.