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

23-82 The Character Group EN
The character size you specify with SR is a percentage of (P2X –
P1X) and (P2Y – P1Y). The printer calculates the actual character
width and height from the specified parameters as follows:
actual width = (width parameter/100) x (P2
X
– P1
X
)
actual height = (height parameter/100) x (P2
Y
– P1
Y
)
For example, suppose P1 and P2 are located at (–6956,–4388) and
(6956,4388), respectively. If you establish relative sizing and specify a
width of 2 and a height of 3.5, the printer determines the actual
character size as follows:
width = || (2/100) x ( 6956 – (–6956) ) = 278.24 plu or
0.695 cm
height = (3.5/100) x (4388 – ( –4388) ) = 307.16 plu or
0.768 cm
If you changed P1 and P2 settings to (100,100) and (5000,5000), but
did not change the SR parameters, the character size would change
as follows:
width = (2/100) x (5000 – 100) = || 98 plu or 0.245 cm
height = (3.5/100) x (5000 – 100) = 171.5 plu or 0.429 cm
Note that in most languages the width of a letter is typically less than
the height. If you set your characters to have a different “aspect ratio”,
they may look odd to your readers.
Note Either negative SR parameters or switching the relative position of P1
and P2 produces mirror-images of labels. When P1 is in the lower
left and P2 is in the upper right, the SR command gives the same
mirroring results as the SI command. However, if you move P1 to the
right of P2, characters are mirrored right-to-left; when you move P1
above P2, characters are mirrored top-to-bottom. When both of these
situations occur (using negative parameters in the SR command
with an unusual P1/P2 position) double mirroring may result in either
direction, in which case the two inversions cancel, and lettering
appears normal.
An SR command remains in effect until another SR command is
executed, an SI command is executed, or the printer is initialized or
set to default conditions.