A codex refers to the specific type of binding. Scrolls are not bound in the same fashion as a codex.
“a quire of manuscript pages held together by stitching: the earliest form of book, replacing the scrolls and wax tablets of earlier times.”
http://dictionary.reference.com/browse/codices
Calling something a ‘codex of scrolls’ is a misnomer. Codexes are an upgrade from scrolls.
Most “codexes” are not bound at all.
Many do not even have ‘hard’ documents.
Your county’s official records system is termed a “codex,” and it consists of a number of “codexes” that are usually full of digital documents these days.
Codex mostly indicates an indexing system that permits easy access to specific pages or sets of pages.