HP PCL/PJL reference (PCL 5 Printer Language) - Technical Reference Manual Part I

5-22 Page Control Commands EN
Vertical Motion Index (VMI) Command
The Vertical Motion Index (VMI) command designates the height of
the rows. (The vertical distance the cursor moves for a Line Feed
operation.)
? & l # C
# = number of 1/48 inch increments between rows.
Default = 8
Range = 0 - Current logical page length up to a maximum of 32767
If the specified VMI is greater than the current logical page length, the
command is ignored.
The value field is valid to 4 decimal places. A Ø in the value field
indicates no vertical movement.
This command affects the Line Feed and Half-Line Feed spacing.
The factory default VMI is 8, which corresponds to 6 lines-per-inch. A
user default VMI can be selected from the control panel using the
FORM menu item (refer to the printer User’s Manual for additional
information).
Example
To designate a VMI of 6 (8 lines-per-inch) send:
?&l6C (6/48 = 1/8 inch/line)
The following equation converts lines-per-inch spacing to VMI:
Note A change in the control panel FORM setting results in a modification
of VMI. If the Page Length command (?&l#P) follows a VMI change,
the physical size of the page is recalculated. Therefore, depending on
the VMI modification made, the printer may request a different paper
size.