Barcodes can be printed anywhere in a document.  If you want to use a barcode you must first define the barcode (using the Barcode Name which is a single character), and it's characteristics in this file.

When you specify a Barcode on a COPY or MOVE CPPD automatically inserts a Barcode Text Enhancement Code within the text of the document (¶C) followed by the single character Barcode Name, plus the digits to be converted into the Barcode. The position where the Barcode is printed depends on the Barcode Definition.

If you wanted to print Barcode 'A' you would specify ¶(the text enhancement character) followed by C, and 'A' followed by the Barcode Number  ¶CA123456789.  This will cause a barcode 123456789 to be printed in the position specified in the X and Y axis, in this file. Note if X/Y are zero the Barcode will be inserted at the COPY/MOVE ‘To’ position.