HP LaserJet 4100 HP PCL/PJL reference (PCL 5 Printer Language) - Technical Ref - Page 202

AC, Anchor Corner This command positions the starting point of any fill pattern. Use AC to ensure that the selected fill pattern is positioned as expected within the figure. AC X,Y[;] or AC [;] Parameter X,Y coordinates Format current units Functional Range -230 to 230 - 1 Default no default The 'anchor corner' is the point at which any fill pattern starts. Setting the anchor corner guarantees that a corner point of the selected fill pattern is at the specified coordinate, aligned vertically and horizontally. z No Parameters - Defaults the anchor corner to the lower-left corner of the PCL Picture Frame (relative to the current coordinate system). Equivalent to (AC0,0). z X,Y Coordinates - The coordinate position defines the position of the starting point for any fill pattern. The following example prints three adjacent squares with fill patterns anchored at the lower-left corner of the PCL Picture Frame. The fill pattern is continuous across each of the squares. In the set of squares below that, each square has an anchor corner set in its own lower-left corner. Notice how this helps distinguish between the adjacent figures. Table 22-3 Example: Changing the Anchor Corner ?E Reset the printer. ?%0B Enter HP-GL/2 mode. IN; Initialize HP-GL/2 mode. 22-6 The Line and Fill Attributes Group EN