HP LaserJet 4100 HP PCL/PJL reference (PCL 5 Printer Language) - Technical Ref - Page 24

Notes Table 17-8 Commands That Include an Automatic Pen Down Command Group CI Circle The Vector Group EA Edge Rectangle Absolute The Polygon Group EP Edge Polygon ER Edge Rectangle Relative EW Edge Wedge FP Fill Polygon RA Fill Rectangle Absolute RR Fill Rectangle Relative WG Fill Wedge LB Label The Character Group SM Symbol Mode The Line and Fill Attributes Group Whenever the printer receives a Pen Down command, it produces a dot at the current pen location. If the pen is already down when the printer receives a command with an automatic Pen Down, the unnecessary dot can mar your final output. For best results, include a Pen Up (PU) command before any command with an automatic Pen Down. Only the portion of the pen falling within the effective window is printed. The pen is centered on a line between the beginning and end points, with half of the pen width falling on either side of this line. The definition of each command tells you whether it has an automatic pen down. If you find that part of your image is not drawn, make sure your command sequence uses the PD command before the affected commands. 17-22 An Introduction to HP-GL/2 Vector Graphics EN