Printronix ANSI Printer manual Clearing The Evfu Memory, Relative Line Slewing

Clearing The EVFU Memory

Table 20. P-Series EVFU Codes - PI Line Disabled or Not Used

	ASCII					Data Bits
Hex	Dec.	Code	8	7	6	5	4	3	2	1	Channel
1F	31	US	0	0	0	1	1	1	1	1	End Load

(X = Undefined, 0, or 1) (1 = High) (0 = Low)

NOTE: The ESC code cannot be used simultaneously as the EVFU VT code and the Special Function Control Code (SFCC). If ESC is used as the SFCC, the EVFU must be used with the PI line enabled and set high. Refer to the appropriate LinePrinter Plus, PGL, and VGL Programmer’s Reference Manual for more information on the SFCC.

Clearing The EVFU Memory

The following actions will reset (clear) the EVFU memory:

1.Sending only the start load code.

2.Sending a start load code followed immediately by an end load code.

3.A second start load code is received, resulting in reinitialization of the EVFU. (This allows the host data to be restarted.)

When the EVFU memory is cleared, the forms length returns to the previously set value and the current print position becomes the top-of-form (TOF).

Relative Line Slewing

Another method of moving paper using the PI line results in vertical 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 criteria must be met:

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

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

3.The EVFU must be the selected Vertical Format Unit.

The Slew Relative configuration and the status of data bits 1-4 determine the number of lines slewed as described in Table 21. (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 will occur regardless of whether the EVFU memory is loaded or not.

If the Double High for One Line attribute is active, n + 1 lines will be slewed rather than n lines.

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