(Why did someone waste her/his time downvoting the parent? His reply was fine.)

I think I get it now. sauoq seems to have gotten right to the heart of the matter. You're generating a PDF file that is supposed to have a code in a special font designed to be read by OCR systems. (I parsed your mentioning of "OCR code" as "the source code for a program that does OCR".) I guess it's just a question of you finding out how to change the font in your output, really. Unfortunately, I don't know anything about that, but I felt you deserved at least a response.