styleguide.org

Disclaimer

I’m making this up as a go, and I don’t know what I’m doing.

This is inspired (very very very loosely) by Unreal Engine’s Coding Standard document, because that is what happens to currently look good, neutral, and clean to me at the moment.

So, the very general guidelines are:

• Indent with tabs, not spaces.
• Braces or equivalent on own line is good, actually (but only when it makes sense).
• When in doubt TitleCase is a reasonable default for naming things, but also be consistent with what you are modifying or working with.

Naming Things

keywords

Use lowercase for keywords, eg entity.

library names, namespaces, etc

Use lowercase. Eg use ieee.numeric_std.all;.

user defined types

Lowercase, use underscores as spaces to be consistent with the ieee type names.

entity and architecture names

Lowercase with underscores.

labels

Lowercase. Underscores.

constants

SCREAM_THE_UNYIELDING_TRUTHS_MIGHTILY

signals

Use title case. Eg signal MyGloriousSignal.

ports and generics

Use title case, but also prefix with an “i” an “o”, or a “g” accordingly. Eg:

entity hail_eris is
	generic (
		gFnord : integer := 10
	);
	port (
		iFhqwhgads : in std_logic;
		oXyzzy : out std_logic
	);
end hail_eris;

indentation

Use tabs instead of spaces. “4” is a good tab width.