32 Line Matrix Printer PCL II Programmer's Reference Manual

Chapter 2 Configuring the PCL-II Emulation with Control Codes

Programmable VFC Using PCL

Programmable VFC’s using PCL seem to cause a lot of problems and

misunderstandings. Most of the misunderstanding concerns the use of the

escape sequence used to set the VFC file. This escape sequence is used to

override the default VFC of the printer. This escape sequence can be hard-

coded into a program or ASCII file.

VFC’s are best understood by reviewing an actual example of how to

implement them. For this discussion, the example consists of a 3.5 inch form

at six lines per inch with several different channels defined for use on the form

to be printed.

1 inch = 6 lines per inch x 3.5 inches = 21 lines; therefore this would be a 21

line form.

NOTE: The TEXT LENGTH command could be used in conjunction with the

standard VFC and accomplish the above requirements. The

assumption is there are reasons to use a customized VFC; this

example has been simplified for clarification purposes.

First, establish the VFC length: with a 3.5” form and 6 LPI print, we have 21

potential lines of print (3.5 x 6 = 21). Refer to the following figure for an

example of the desired finished output.

There are many methods to accomplish this task. The simplest way is to

provide a “1” in CH3 (Channel 3) for all possible print lines and simply call

CH3 for each line (including blank lines). This is called “line counting” and

leaves the burden of positioning with the programmer (adding or deleting a

line causes an adjustment elsewhere to be made).

EXAMPLE FORM

Line 1 Company name

Line 2 Street address

Line 3

Line 4

Line 5

Line 6

Line 7 Opening line

Line 8

Line 9

Line 10 Body

Line 11 Body

Line 12 Body

Line 13

Line 14

Line 15

Line 16

Line 17 Closing line

Line 18

Line 19

Line 20 P.S. line

Line 21