Nios® V Embedded Processor Design Handbook

ID 726952
Date 7/08/2024
Public
Document Table of Contents

6.2.3.2.2. 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.

Follow these steps to add the signals to the Signal Tap Node list for monitoring:

  1. Compile the design by clicking Processing > Start Compilation.
  2. In the Signal Tap logic analyzer, perform Double-click to add nodes.
  3. The Node Finder appears, allowing you to find and add the signals in your design.
  4. Select Post-Compilation to find signal names present after design compilation.
    Figure 108. Node Finder
  5. Search for the Nios® V processor nodes in the following table. Then click the > button.
    Table 40.   Nios® V Processor Nodes
    Nodes Pipeline Stage Description Representation
    *D_instr_pc[31..0] Instruction Decode (D) Program Counter Memory address of the instruction being fetched.
    *D_instr_word[31..0] Instruction Word Fetched 32-bits instruction word.
    *D_instr_valid Instruction Valid Valid instruction to continue E stage.
    *E_instr_pc[31..0] Instruction Execute (E) Program Counter Memory address of the instruction being decoded.
    *E_instr_word[6..0] Instruction Word 7-bits opcode from 32-bits instruction word.
    *E_instr_valid Instruction Valid Valid instruction to continue M stage.
    *M0_instr_pc[31..0] Memory (M) Program Counter Memory address of the instruction being executed.
    *M0_instr_valid Instruction Valid Valid instruction to continue Write Back stage.
  6. Click Insert. The nodes are added to the Setup tab signal list in the Signal Tap logic analyzer GUI.
  7. Specify how the logic analyzer uses the signal by enabling or disabling the Data Enable and Trigger Enable option for the signal:
    • Data Enable—disabling this option stops the capture of data.
    • Trigger Enable—disabling this option exclude the signal from the triggering conditions.
Figure 109.  Signal Tap Setup tab