Printronix P7000 Programmer's Reference Manual page 57

Vertical Bar Codes
Commas and spaces function as they do for horizontal bar codes. A comma
does not add any space, and a space adds .1" between the bar codes. The
quiet zones rotate with the symbol leaving almost no horizontal separation
between bar codes on the same line.
Line 10 either enables or disables printing of the human readable line.
Commas With Human Readable Line:
Commas Without Human Readable Line:
Spaces With Human Readable Line:
Spaces Without Human Readable Line:
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