Printronix LQH-HWTM manual Paper Motion Using Line Feeds and Form Feeds

C Vertical Paper Motion

Introduction

There are three methods of advancing the print position with the IGP which are explained in this appendix:

1.Using line feeds or form feeds;

2.Using the paper instruction (PI) line; or

3.Using the Electronic Vertical Format Unit (EVFU).

Paper Motion Using Line Feeds and Form Feeds

The most common method of advancing the print position with IGP is through the use of line feeds and form feeds. A line feed moves the print position down a distance determined by the current line spacing (lpi). In the Normal mode, a form feed character advances the print position to the top of the next page; in the Execute mode, a form feed advances the print position to the top of the next form. Form length is determined by the CREATE command.

Paper Motion Using the PI Line (Relative Line Slewing)

The method of moving the print position using the PI line results in vertical slews of a specified number of lines relative to the current print position (rather than slewing to a specific line). For this to occur, the following criteria must be met:

1.The PI line must be enabled and set high; and

2.Data bit 5 must be 1 (set).

When a number of blank lines will be skipped on a form, (called “paper slewing”) another method of paper motion may be used. The PI signal can be detected by the IGP as the 8th data bit in a serial interface, or a separate input line in a parallel interface. (Refer to the EN-PI/DIS-PI command and the PION/PIOFF commands on page 79.) When the PI signal is used, bits 6 and 7 are interpreted as 0 values, and characters hex 10 through 1F are interpreted as binary slew commands.

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