JPS55166731A - Data protection system - Google Patents

Data protection system

Info

Publication number
JPS55166731A
JPS55166731A JP7431679A JP7431679A JPS55166731A JP S55166731 A JPS55166731 A JP S55166731A JP 7431679 A JP7431679 A JP 7431679A JP 7431679 A JP7431679 A JP 7431679A JP S55166731 A JPS55166731 A JP S55166731A
Authority
JP
Japan
Prior art keywords
keyboard
protection system
data protection
key
swl
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP7431679A
Other languages
Japanese (ja)
Inventor
Minoru Machida
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Canon Inc
Original Assignee
Canon Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Canon Inc filed Critical Canon Inc
Priority to JP7431679A priority Critical patent/JPS55166731A/en
Publication of JPS55166731A publication Critical patent/JPS55166731A/en
Pending legal-status Critical Current

Links

Landscapes

  • Input From Keyboards Or The Like (AREA)

Abstract

PURPOSE: To protect data up to the current point in an interruption of processing, by adding a change-over switch for locking a keyboard, a display method and a few gates.
CONSTITUTION: With the common terminal of keyboard lock switch SW grounded (SWL is at a low level.), keyboard control logic part invalidates the depression of any key. In this case, since inverter I generates a high-level output, key operation makes transistor TR conduct via AND gate A5, and consequently a light emission diode comes on, showing that the keyboard is being locked.
COPYRIGHT: (C)1980,JPO&Japio
JP7431679A 1979-06-13 1979-06-13 Data protection system Pending JPS55166731A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7431679A JPS55166731A (en) 1979-06-13 1979-06-13 Data protection system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7431679A JPS55166731A (en) 1979-06-13 1979-06-13 Data protection system

Publications (1)

Publication Number Publication Date
JPS55166731A true JPS55166731A (en) 1980-12-26

Family

ID=13543584

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7431679A Pending JPS55166731A (en) 1979-06-13 1979-06-13 Data protection system

Country Status (1)

Country Link
JP (1) JPS55166731A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0143045A2 (en) * 1983-11-14 1985-05-29 Digital Equipment Corporation Circuit for selecting and locking of operational function circuitry
CN102547509A (en) * 2011-12-15 2012-07-04 无锡中星微电子有限公司 Method, apparatus and device for controlling bluetooth headset keyboard

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0143045A2 (en) * 1983-11-14 1985-05-29 Digital Equipment Corporation Circuit for selecting and locking of operational function circuitry
EP0143045A3 (en) * 1983-11-14 1987-08-12 Digital Equipment Corporation Circuit for selecting and locking in operation function circuitry
CN102547509A (en) * 2011-12-15 2012-07-04 无锡中星微电子有限公司 Method, apparatus and device for controlling bluetooth headset keyboard

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