Unidirectional Printing - Epson DLQ-3500 User Manual

top-of-form position
The position on the paper that the printer recognizes as the first printable line.
This is the default top-margin position.

unidirectional printing

Printing in which the print head prints in one direction only. Unidirectional
printing is useful for printing graphics because it allows precise vertical
alignment. You can select unidirectional printing in the printer's default-setting
mode. See also "bidirectional printing".
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