公开(公告)号：DE2536586A1

公开(公告)日：1976-03-18

申请号：DE2536586

申请日：1975-08-16

Applicant: IBM

Inventor： GIANNUZZI ROBERT JOSEPH ,  LANGDON JUN GLEN GEORGE ,  PASTERNAK EDWARD

IPC: G06F3/023 ,  G06F3/147 ,  G06F15/02 ,  H01H13/84 ,  G06F11/00

Abstract: A keyboard operated programmable electronic calculator is provided with a light display and individual key lights for the numeric and function keys. A program is entered into storage by operation of the numeric and function keys when the calculator is activated to the program mode by a first control key. The program is read out of storage by operation of a second control key. Control logic under control of the calculator CPU operates the light display and the individual key lights in response to manual operation of the second control key to identify the program step and its program parameter for checking purposes.