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  1. SystemVerilog RTL Foundations6

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SystemVerilog RTL FoundationsPublished

The logic Type & Four-State Debugging

Replace wire/reg with logic, then deliberately drive a net from two places and read the resulting X in the waveform to learn what four-state simulation is actually telling you.

Beginner~30 minSelf-checking testbench1 challenge
Concepts covered
  • logic vs wire/reg
  • Four-state values
  • X propagation
This lab is part of SystemVerilog Labs

Unlock the complete lab — language semantics, hardware meaning, complete SystemVerilog source, a self-checking testbench, compiler-diagnostic evidence, debugging walkthroughs and challenges — with the SystemVerilog Labs package.

  • Language semantics & hardware meaning
  • Complete, runnable SystemVerilog
  • Self-checking testbench
  • Compiler-diagnostic evidence
  • Debugging walkthroughs
  • 1 progressive challenge
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