IBM 4400 Relative Line Slewing

Relative Line Slewing
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Relative Line Slewing
Another method of moving paper using the PI signal line results in ver tical
slews of a specified number of lines within the form relative to the current print
line (rather than slewing to a specific line). For this to occur, three c riteria
must be met:
•The PI signal line must be enabled and set high;
•Data bit5 must be 1 (set); and
•The EVFU must be the selected Vertical Format Unit.
The Slew Relative configuration and the state of data bits 1 through 4
determine the number of lines slewed as described in Table 79. (Note that the
state of data bit 5 is the difference between line slewing and using the
interface lines as EVFU channel codes.) As long as the EVFU is selected, this
type of vertical paper motion occurs regardless of whether the EVFU memory
is loaded or not.
If the Double High for One Line attribute is active,
n +1linesareslewed
rather than
n lines.