Embedded Design Handbook

ID 683689
Date 8/28/2023
Public
Document Table of Contents

4.4.2.4. Program Counter Trace Information

The Nios® II processor can generate complete and accurate program counter trace information. However, the GNU profiler does not use this information. To generate this information, you must have a Nios® II processor configured with a JTAG debug module of level 3 or greater. The level 3 JTAG debug module creates on-chip trace data. You can capture approximately a dozen instructions in the on-chip trace buffer.

You can obtain a much larger trace by configuring a Nios® II core with a level 4 JTAG debug module to generate off-chip trace information; however, you need a First Silicon Solutions, Inc. (FS2) or Lauterbach Datentechnik GmBH (Lauterbach) (www.lauterbach.com) hardware to collect this off-chip trace data.

For more information about the Lauterbach hardware, refer to the “Debuggers” section in the Debugging Nios® II Designs chapter.