What You'll Learn In This Chapter; Hp-Gl Instructions Covered; Terms You Should Understand - HP 7470A Interfacing And Programming Manual

Chapter
Establishing Boundaries
and Units
What You'll Learn in This Chapter
In this chapter you will learn about the plotting area, how to define a
point in this area, and the two kinds of units used to describe the plot­
ting area. After reading this chapter, you will be able to decide which
units to use for your data. In addition, you will be able to scale the
plotting area into user units appropriate for your data, and to set or
read the current scaling points. You will be able to restrict plotting to
only a portion of the plotting area, and read the current limits of the
plotting area.
HP-GL Instructions Covered
IP The Input PI and P2 Instruction
OP The Output PI and P2 Instruction
SC The Scale Instruction
IW The Input Window Instruction
OW The Output Window Instruction
Terms You Should Understand
Scaling — dividing the plotting area into units convenient for your ap­
plication. Units need not be the same physical size in both axes, nor do
there need to be an equal number of units in the X- and Y-axes.
Scaling Points — the points on the plotting surface moved to when the
front panel buttons P1 and P2 are pressed. These points are assigned the
user-unit values specified by the parameters of the scaling instruction
SC.
Window — that part of the plotting area in which plotting of points,
lines, and labels can occur. At power on, the window is set to the
mechanical limits of the plotter. Nothing can be drawn outside the
current window.
Clipping — restricting plotting to a portion of the plotting area by
establishing a window of a certain size.
ESTABLISHING BOUNDARIES AND UNITS 2-1