Dascom T2250 User Guide IGP for Dot Matrix Printers - Manual (Page 33)

Chapter 2: Emulations
33
Setting Vertical Format
The top of the first line of print on a page is called the top-of-form (TOF) position. Vertical
position is measured from this point. The form length is the distance from one TOF to the next.
The bottom-of-form (BOF) skip is the distance between the last line of print on the page and the
next TOF. Once the TOF and form length have been set, the paper will automatically advance to
the next TOF whenever the print position advances into the BOF skip area. Vertical formatting
includes the following settings:
Physical length of the total form.
Position of the first printed line on a form (TOF).
Position of bottom-of-form and/or bottom-of-form skip.
Position of any other vertical stops on a form.
There are three ways to set vertical format. One way involves using the menus on the printer to
set the desired parameter values through the control panel. The other ways involve sending
escape sequences or control codes from the host computer.
Form Length Select
In the IEEE 1284 interface the form length can be selected through the control panel or by
sending the Form Length Select (FLS) escape sequence from the host. The basic FLS escape
sequence is:
ESC [ n t
1B 5B 74
Where:
n = Form Length
If n = :
0, form length is 11 inches.
1, form length is 12 inches.
2–255, form length is equal to the value of n (in lines).
The FLS Command resets the current paper position as the TOF. Make sure the
paper is aligned at the desired top-of-form before sending the FLS Command.
To calculate form length, multiply the form length in inches by the lines per inch.
For instance, a 15.5" form printed at 6 LPI has a form length of 93 lines:
15.5" Form Length x 6 LPI = 93 (Total lines on form)
To set the form length for a 15.5" form, send the sequence:
ESC [ 93 t
1B 5B 3933 74
Even though the form length can be set in number of lines, the printer divides the Form Length in
lines by the LPI setting and stores the form length in inches, not number of lines. Subsequent
changes in LPI will not change the physical form length.