Abstract: A media level indicator is provided to identify the amount of media in an input stack of a sheet processing device. The media level indicator includes an odometer mechanism configured to survey the printer's feed mechanism so that it may quantify movement of a selected sheet during a predetermined feed operation. The quantified movement thereafter is interpreted to indicate the amount of media in the input stack.

Abstract: A method of monitoring and controlling the quality of pen markings on a plotting medium by qualifying each pen based on optically sensing across a sample line drawn on an actual medium. During each subsequent plotting task of a particular pen which has been qualified, an actual line plot is optically sensed across a selected point to make a comparison with the sample line. If the actual line plot is unsatisfactory, the deficient pen is replaced and the plot is restarted from the beginning, or retraced from the last good verification, or is stopped to allow the user to select an appropriate corrective procedure.

Abstract: A plotter continuously performs a dynamic sort on incoming vectors to be plotted and stores the sorted vectors by color in bins within a memory. At the same time that the sort is being performed, the plotter selects the bin containing the most vectors and plots all of the vectors from that bin before selecting another bin.