General purpose calculator having selective data storage, data conversion and time-keeping capabilities

摘要

A battery-powered hand-held calculator for performing arithmetic, trigonometric, and logarithmic functions and displaying the results thereof is provided with the capability of automatically storing the last displayed number in an auxiliary storage register whenever the next succeeding function to be performed would destroy that number. That number may be recalled from the auxiliary storage register by simply depressing a prefix key and a Last-X function key.