What is Verilog?

Verilog in the explanations

• In Verilog, signals driven by assign statements or module outputs are declared wire, and signals assigned inside always blocks are declared reg.

  What is the difference between wire and reg in Verilog?

• Verilog does not reject assignments between different widths but truncates or extends them, so checking width mismatches with a lint tool is effective.

  In Verilog, two 8-bit signals a and b are added and assigne…

• Besides 0 and 1, Verilog signals can be X (unknown) and Z (high impedance, undriven).

  Which set of values makes up the four-state logic used in V…

Questions that mention Verilog (21)

1. What is a major difference between a description written in an HDL such as Verilog and a software program in a language such as C?
2. What is the purpose of a module in Verilog?
3. What is the difference between wire and reg in Verilog?
4. What circuit does the Verilog assign statement above represent?
5. What circuit does logic synthesis create from the Verilog above?
6. How does Verilog's nonblocking assignment (<=) behave?
7. What is the common guideline for choosing assignment types in Verilog?
8. What does writing "always @(*)" mean in Verilog?
9. Which Verilog construct is ignored by logic synthesis and does not become hardware (a simulation-only construct)?
10. In Verilog, two 8-bit signals a and b are added and assigned to an 8-bit signal s (assign s = a + b;). What should be watched for?
11. Which set of values makes up the four-state logic used in Verilog simulation?
12. In the code above, when sel is X, Verilog simulation selects b for y. Why is this a problem for verification?
13. What is the advantage of using SystemVerilog's always_ff and always_comb instead of Verilog's always?
14. What is the difference between Verilog's equality operators "==" and "==="?
15. Which is the correct order of a typical digital LSI design flow?

Related terms

SystemVerilog Logic synthesis Hardware description language (HDL) RTL (register-transfer level) Flip-flop Testbench Netlist Tape-out SPICE Nonblocking assignment