PU - Pen up ; PD - Pen down ; PA - Plot absolute - Page 334

2001/10/02 

CHAPTER 9 HP-GL - 9 

PU - Pen up  

PU [ X,Y [,...]] [;] 

X ; X coordinate of the cursor movement destination 

Y ; Y coordinate of the cursor movement destination 

• 

X and Y are either relative or absolute, depending on whether a PA or a PR was the last plot command 
executed.  The absolute coordinates are set as default. 

• 

Moves the cursor to the specified coordinates after raising the pen. 

• 

Using this instruction without a parameter field  raises the pen without changing the cursor position. 

• 

When scaling is on, user coordinates are used. 

• 

Also, when scaling has been performed, the values for X and Y are real numbers. 

• 

When scaling is off graphics units are used. 

• 

When there is no scaling, the coordinates values for X and Y are integer numbers. 

Current position

(X1, Y1)

(X2,Y2)

(X3, Y3)

(Xn, Yn)

PD - Pen down 

PD [ X, Y [,...]] [;] 

X ; X coordinate of the cursor movement destination 

Y ; Y coordinate of the cursor movement destination 

• 

X and Y are either relative or absolute, depending on whether a PA or a PR was the last plot command 
executed.  The absolute coordinates are set as default. 

• 

Moves the cursor to the specified coordinates after lowering the pen.  (This plots a straight line.) 

• 

Using this instruction without a parameter lowers the pen without changing the cursor position.  ( One dot is 
plotted.) 

• 

When scaling has been performed,  the cursor is moved by user coordinates. 

• 

Also, when scaling has been performed, the values for X and Y are real numbers. 

• 

When there is no scaling,  the cursor is moved by absolute coordinates in graphics units. 

• 

When there is no scaling, the coordinate values for X and Y are integer numbers. 

Current position

(X1, Y1)

(X2,Y2)

(X3, Y3)

(Xn, Yn)

PA - Plot absolute 

PA [X, Y [,...]] [;] 

X ; X coordinate of the cursor movement destination 

Y ; Y coordinate of the cursor movement destination 

• 

X and Y are absolute values in user units or graphics units. 

• 

Moves t he cursor to the specified coordinates. 

• 

Plots a straight line only when the pen is down. 

• 

When scaling has been performed,  the values for X and Y are integer numbers. 

• 

When there is no scaling,  the cursor is moved by absolute coordinates in graphics units. 

• 

When there is no scaling,  the coordinate values for X and Y are integer numbers.