\input upca % inputing macros to the document

\module=0.5mm % setting module width (width of single bar or space) of the code; default 0.33mm

\height=50mm % setting height of the code; default 25.9mm

\upca{03600029145} % produces UPC-A barcode, the check digit will be calculated

\upca{036000291454} % produces the same code, the check digit is not controled

\end