HP 7475a, Руководство по эксплуатации и взаимосвязи

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The
Scaling Points PI and P2
On power-up. the default location of scaling point PI is in the lower-left
corner of AI A4 size paper or in the upper-left corner of BI A3 size paper.
In each case, the default location of scaling point P2 is in the corner
opposite from Pl. The exact default coordinate locations of scaling
points PI and P2 are shown in the following table, in plotter units, for
the different paper sizes. These default coordinate values define oppo­
site corners of a rectangular area that is centered on the associated size
of paper. Regardless of its size, the rectangular area defined by Pl and
P2 will hereafter be referred to as the " Pl ! P2 frame."
Default Coordinate Values for Scaling Points PI and P2
Paper
Size
A
A4
B
A3
HP-GL Scaling
Default Scaling Points (Plotter Units)
Plx,Ply
2 50, 59 6
603 ,52 1
522 , 259
17 0, 602
P2x,P2y
10250,7796
1 0 603 , 772 1
15722 , 10 2 59
15370, 10 602
Scaling points P I and P2 can be used in conjunction with the
Hp·GL
instruction,
se,
to enable you to plot in user units that are convenient
to your application. The size of the user unit is determined by the phys­
ical dimensions of the P lIP2 frame and by the parameters of the
se
instruction. These parameters assign user-unit coordinates to PI
and P2 and divide (scale) the entire plotting area, not just the PlIP2
frame, into a user-unit grid. Grid spacing can be anisotropic (unequal
in X and Y) or isotropic (equal in X and Y) and each axis can have a
different number of user units. For example, the HP - GL instruction
SCO , 12,0, 1 000 scales the PI/P2 frame into 1 2 user units in the X-axis,
representing months, and into 1000 user units in the Y-axis, represent­
ing total sales in dollars.
Scaling points PI and P2 retain the assigned user-unit values until
scaling is turned off or another
se
instruction redefines their user-unit
coordinate values. Therefore, the size of a user unit will change with
any change in the distance between PI and P2. This feature allows you
to fit the same plot on any size of paper.
PLOTTER OPERATION
2·7