| 摘要 |
PURPOSE:To improve the safety of input of a secret number by providing an input/output control means of key switches to be operated and changing the arrangement of key switches at random when a password number is inputted. CONSTITUTION:A keyboard 1 with a secret number input function consists of a keyboard part 2, an input/output control part 3, and a display part 4, and a password number input command and key output signals from a central processing part 10 of an incorporated device 9 are transmitted and received in the input/output control part 3. When the secret number input command is inputted, its flag SC is set, and a random number generator for displaying a number on the display part 4 is accessed, and optional numbers are selected from object numbers at random and are displayed successively and are stored in a key retrieval table. Thus, the arrangement of display contents on the display part 4 is changed at random each time when the secret number input command is inputted, and the input number is prevented from being known by others. |
