| 摘要 |
A digitizer cursor is provided with a multifunctional control panel. The panel is comprised of a multiplicity of switches for defining various modes of cursor operation in use with a digitizer coordinate axes grid assembly or pad. Novel circuitry provides for a cursor of convenient size with a complex control panel in combination with a point locating device used in conjunction with the coordinate grid assembly. The circuitry provides for electrical communication through a coaxial cable permitting easy maneuverability of the cursor assembly relative to the pad and a simple electrical path for processing of the cursor coil induced point location signal, to determine coordinate location, and the cursor control signals originating as a function of switch operation initiated on the cursor panel by the operator. One digitizer grid pattern is used for each of two coordinate axes, i.e. X and Y. Each grid pattern is used for coarse and fine digitizing to determine cursor positioning on each respective axis. The digitizer has two basic modes of operation which relate to digitally representing the position of a cursor on a grid pattern. The first mode is for coarse digitizing designed to identify the position of the cursor within 11/2 grid lines of its actual position on the grid. The second mode is the fine digitizing mode which is operative to positively locate the cursor at its actual position within a triad of grid lines which have been identified through the coarse digitizing operation. Both modes are operative for each of the two axes. For coarse digitizing, a sequential line-to-ling pulsing technique is applied. For fine digitizing, a pulsed three phase system is utilized and any odd multiple of three grid lines.
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