Overview

Defines Code 39 (the 43-character alphanumeric barcode) and, in its Annex, Codabar (NW-7). Covers the 9-element-per-character module patterns, the start/stop sentinel, the optional mod-43 check character, and the wide-to-narrow ratio.

Why it matters for RFID

The international-standard reference for Code 39, LOGMARS, and Codabar. The 43-character alphabet (0-9 A-Z and a few punctuation marks) is the smallest practical character set for general-purpose alphanumeric barcodes.

Official document

https://www.iso.org/standard/43897.html