Programmable calculator including key-log printing means

Claim 1

An electronic calculator having a plurality of operating modes including the manual operating mode and the automatic operating mode, said calculator comprising: a keyboard input unit including numeric and non-numeric keys having unique key codes for entering information into the calculator; a first memory unit into which information may be written and from which information may be read; a second memory unit for storing routines and subroutines to be executed by the calculator in performing selected functions; processing means responsive to information from the keyboard input unit or the first memory unit and to operating modes of the calculator for selectively executing one or more of the routines and subroutines stored in the second memory unit to perform selected functions employing information from the keyboard input and first memory units; an output printer unit coupled to the processing means for providing an output indication of the functions performed by the calculator; and control means coupled to the processing means and the output printer unit for causing the key code of the numeric and several of the non-numeric keys actuated to be printed by the output printer unit in response to actuation of a first non-numeric key in the manual operating mode; said control means including logic means coupled to the processing means and output printer unit for causing the key code and mnemonic representation of each program step of programs stored in the first memory unit to be printed by the output printer unit in response to the actuation of a second non-numeric key in the automatic operating mode.