Nios® V Embedded Processor Design Handbook

ID 726952
Date 12/09/2025
Public
Document Table of Contents

4.2.3.2.2. Adding Signals for Monitoring and Debugging

You can add any signals or interfaces within the processor system for monitoring and debugging. The Nios® V processor's interested signals are the nodes within it, allowing the Signal Tap Logic analyzer to capture the opcodes executed by the processor.

When you add the Nios V processor signal tap plug-in to your system, you must specify which Nios® V processor you want to monitor and, optionally, the processor's software image (an .elf file). The Nios® V processor Signal Tap plug-in processes the .elf file to extract symbol information. The plug-in uses the .elf file during configuration to specify trigger conditions.

To add the Nios® V processor Signal Tap plug-in to your system, follow these steps:
  1. In the Quartus® Prime window, on the Processing menu, point to Start, and then click Start Analysis & Elaboration.
  2. In the Signal Tap window, right-click in the Signal Tap node list
  3. Point to Add Nodes with Plug-In and click Nios® V .
    Figure 34. Add Nodes with Plug-In
  4. Select the Nios® V processor instance you want to monitor with the plug-in.
    Figure 35. Select Processor Instance
  5. Click OK.
  6. Optionally specify the location of the ELF.
    Figure 36. Specify Location of the ELF
  7. Click OK.
Figure 37.  Nios® V Processor Signal Tap Plug-in Setup
You can change the ELF that the Nios® V Processor Signal Tap Plug-in uses at any time by performing the following steps:
  1. In the Signal Tap window, click the Setup tab.
  2. In the Signal Tap node list, right-click on the Nios® V processor Signal Tap plug-in instance you want to modify and click Plug-In Options. The configuration options for the plug-in appear.
Note: Two Nios® V Processor Signal Tap plug-in instances cannot monitor the same Nios V processor. If you add more than one instance of the Nios® V Processor Signal Tap plug-in per processor, an error message appears.