Among the oldest known legal codes, the Code of Hammurabi is quite detailed. You can see a translation here.
As you can see from the text, it is intensively concentrated on legal formulations. Like most legal systems, it does not derive from an enumerated set of principles, but rather is a series of prescriptions, transgressions, and penalties for transgressions.
Probably the first significant professional ethical code, it is still in use today; there is a modern revision that has become popular in the United States.