This invention relates to processing of digital information and, more particularly, to an improved interface for coupling numerical information, such as digital coordinate information, into a hand-held calculator.
In recent years hand-held calculators have come into widespread use. Advances in integrated circuit and microcircuit technology have reduced the cost of calculators having substantial computing and programming ability to the point where technical personnel have such calculators available for individual use. The availability of these calculators has enhanced the efficiency of technical personnel since, for many types of calculations, it is no longer necessary to wait for the availability of larger non-portable computers. However, there are certain aspects of using hand-held calculators which are quite limiting on efficiency. For example, when numerical information is being generated by another device, it is necessary for the user of a hand-held calculator to read the information generated by the companion device and then manually enter the numerical information into the hand-held calculator via the calculator keyboard. One instance where this procedure might be followed is where a hand-held calculator is used to store data and perform calculations on numerical information generated by a graphical digitizer which produces digital information, generally in a binary coded form, representative of the instantaneous position of a movable element such as a stylus or cursor. In such case, the necessity of having an operator read output information from the graphical digitizer and manually enter such information into a calculator via its keyboard is a relatively slow and inefficient process. Also, this procedure increases the possibility of human error which can arise from a misreading of data or mistakes in the keyboard entry process.
It is an object of the present invention to provide solution to the problem inherent in the prior art as set forth.