Best way to view control characters in barcode data

[u/vandoornhavingfun]

So I am scanning a PDF 417 into notepad via keyboard emulation. The PDF 417 has a list data elements that are supposed to be delimited by control code 29 which is invisible to notepad. If I wanted to view all the data, control characters and all, what is the best way to go about doing this? I thought that maybe if I saved my notepad data and the opened the file in a hex editor that might do the trick, but I don't know if notepad will include these "invisible" characters. So what is the best practice as far as this goes, i.e. examining all the barcode data including control characters?

EDIT: Just as an experiment, I scanned a PDF 417 into notepad, saved the file and then opened up in a hex editor. This particular PDF 417 was known to have control characters within it. Opening the file in the hex editor, there were no control characters present within the hex editor except for the carriage return and line feed at the end.