Printronix MVP Series - Manual (Page 114)

EVFU 6–2
Introduction
The Electronic Vertical Format Unit (EVFU) is a software–controlled
vertical formatter you load and operate from the host computer. When you
load the EVFU, it disables page perforation skip (Configuration Option 50)
and forms length at printer power–up (Configuration Option 52).
When you use EVFU to define print lines on a form, it increases system
efficiency because it allows the printer to slew paper to a predetermined line
with a single command.
Programming EVFU Memory
The EVFU memory is loaded with a program of line identification codes,
one for each of the lines of the form being printed. A paper instruction (PI) is
necessary with a Dataproducts interface, but is optional with a Centronics
Interface. Refer to Chapter 8 to learn differences between the Dataproducts
and Centronics interface.
Loading EFVU memory begins with a Start Load and ends with an End Load
command after the last identification code. The TOF indicator lights when
the EVFU receives the End Load command, signifying a successful program
load.
Start Load Code – 6H
The EVFU must be enabled via the control panel before the EVFU can be
loaded. While the EVFU is enabled, an E should appear on the first line of
the ONLINE/OFFLINE display. The EVFU Start Load code of 6E (hex) with
the paper instruction line (PI) high initiates the EVFU memory load routine.
Subsequent data received is considered channel assignments until the end
load code is received. The PI line is a hardware interface signal that is held
either high or low. Refer to the Interfaces chapter for PI and data line printout
information.