To define the properties of a barcode, you must first select the barcode and set basic characteristics in the Field tab of the Object palette. The number and type of barcode properties vary from one barcode to another.
In the Data Length box, type the length of the data. If you are defining an MSI barcode, the data length must be a value between 1 and 14. The MSI, UPC-E, UPC EAN2, UPC EAN5, US Postal Zip-5, US Postal DPBC, and US Postal Standard barcode formats have fixed data lengths that cannot be changed.
If an End Char or Start Char box is displayed, type the end character, start character, or both. If you are defining a Codabar barcode, the valid end and start characters are A, B, C, D, a, b, c, d, *, N, T, E, n, t, and e. If you are defining a Code 49 barcode, the valid start characters are A, 1, 2, 3, 4, and 5.
If a Wide/Narrow Ratio box is displayed, type a wide-narrow-ratio value. For Codabar, Code 2 of 5 (Industrial, Interleaved, and Matrix), and Code 3 of 9, the wide-narrow-ratio value must be a value from 2.2 to 3.0. For Code 11, Logmars, MSI, and Plessey barcodes, the value must be a value from 2.0 to 3.0.
See also 

To define barcode field properties