Question

What best practices should be observed when implementing HDL code?

What are the commonalities and differences when compared to more common software development fields?

Answer 1

The best book on this topic is Reuse Methodology Manual. It covers both VHDL and Verilog.

And in particular some issues that don’t have an exact match in software:

• No latches
• Be careful with resets
• Check your internal and external timing
• Use only synthesizable code
• Register your outputs of all modules
• Be careful with blocking vs. non-blocking assignments
• Be careful with sensitive lists for combinatorial logic (or use @(*) in Verilog)

Some that are the same include

• Use CM
• Have code reviews
• Test (simulate) your code
• Reuse code when appropriate
• Have an up-to-date schedule
• Have a spec or use cases or an Agile customer