Streaming Trace

To analyze the program behavior on target systems, code debugging can be used, but with increasingly complicated systems it is not always possible to use a stop-and-go mechanism to detect program glitches. There is a need to gather data in real-time while the device is running at full speed.

Cortex-M processor-based devices use CoreSight Macrocells for real-time tracing like the Embedded Trace Macrocell, Instrumentation Trace Macrocell, and Data Watchpoint and Trace Unit. Real-time trace data are pushed to the host's hard disk via the debugger adapter, from where µVision picks up the data to show them in µVision Windows.

Streaming trace (real-time trace) when combined with ULINKpro, offers many advantages:

• Trace data are delivered in real-time to the host computer.
• The data amount is limited by the host computer only (hard disk).
• Tracing is possible for minutes, hours, or longer.
• Modern computers can handle traced data instantly.

The delivered trace data are:

• Program counter values.
• Data reads and writes.
• Event counters.
• Exception entry and returns.
• Timestamps and CPU cycles used.
• Executed instructions.

Streaming data are output on a 4-bit dedicated trace bus and are captured by special debugger adapters, such as ULINKpro.

Note

• Not all Cortex-M processor-based devices have an Embedded Trace Macrocell.