JPS5453509A - Magnetic disc apparatus - Google Patents

Magnetic disc apparatus

Info

Publication number
JPS5453509A
JPS5453509A JP11959277A JP11959277A JPS5453509A JP S5453509 A JPS5453509 A JP S5453509A JP 11959277 A JP11959277 A JP 11959277A JP 11959277 A JP11959277 A JP 11959277A JP S5453509 A JPS5453509 A JP S5453509A
Authority
JP
Japan
Prior art keywords
gate
reading
switch
abled
writing
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
JP11959277A
Other languages
Japanese (ja)
Inventor
Koichi Yamamoto
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.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co Ltd
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 NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP11959277A priority Critical patent/JPS5453509A/en
Publication of JPS5453509A publication Critical patent/JPS5453509A/en
Pending legal-status Critical Current

Links

Landscapes

  • Signal Processing For Digital Recording And Reproducing (AREA)

Abstract

PURPOSE: To improve the protection functions of data by controlling inhibition of writing and reading, etc. through a switch with key.
CONSTITUTION: When a switch 2 with key is so locked that switches 1-1, 1-2 connect to contacts (a), (a'), then an AND gate 8 is opened via OR gate 6 by the high level output from the switches 1-1, 1-2, and the reading by the output of a read amplifier 4 and a write driver 5 via OR gate 7, AND gate 9 are enabled, whereby writable state is put. In a similar manner, the switch is locked in the state where wiriting and reading are disabled, only the writing is abled or only the reading is abled, thus the data control using magnetic discs is satisfactorily controlled
COPYRIGHT: (C)1979,JPO&Japio
JP11959277A 1977-10-04 1977-10-04 Magnetic disc apparatus Pending JPS5453509A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11959277A JPS5453509A (en) 1977-10-04 1977-10-04 Magnetic disc apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11959277A JPS5453509A (en) 1977-10-04 1977-10-04 Magnetic disc apparatus

Publications (1)

Publication Number Publication Date
JPS5453509A true JPS5453509A (en) 1979-04-26

Family

ID=14765184

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11959277A Pending JPS5453509A (en) 1977-10-04 1977-10-04 Magnetic disc apparatus

Country Status (1)

Country Link
JP (1) JPS5453509A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS613361A (en) * 1984-06-15 1986-01-09 Matsushita Electric Ind Co Ltd Videodisk player
JPS62200554A (en) * 1986-02-26 1987-09-04 Akai Electric Co Ltd Reproducing device
US5956194A (en) * 1994-09-16 1999-09-21 Kabushiki Kaisha Toshiba Data storage apparatus
WO2000049753A3 (en) * 1999-02-16 2002-01-10 Browne Hendrik A A secure computer system and access thereto
EP1806746A2 (en) * 2006-01-06 2007-07-11 Hitachi Global Storage Technologies B. V. Disk unit, magnetic disk unit and information storage unit

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52122114A (en) * 1976-04-07 1977-10-14 Hitachi Ltd Magnetic disc drive apparatus

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52122114A (en) * 1976-04-07 1977-10-14 Hitachi Ltd Magnetic disc drive apparatus

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS613361A (en) * 1984-06-15 1986-01-09 Matsushita Electric Ind Co Ltd Videodisk player
JPS62200554A (en) * 1986-02-26 1987-09-04 Akai Electric Co Ltd Reproducing device
US5956194A (en) * 1994-09-16 1999-09-21 Kabushiki Kaisha Toshiba Data storage apparatus
US6212026B1 (en) 1994-09-16 2001-04-03 Kabushiki Kaisha Toshiba Data storage apparatus having an impact detecting mechanism
WO2000049753A3 (en) * 1999-02-16 2002-01-10 Browne Hendrik A A secure computer system and access thereto
EP1806746A2 (en) * 2006-01-06 2007-07-11 Hitachi Global Storage Technologies B. V. Disk unit, magnetic disk unit and information storage unit
EP1806746A3 (en) * 2006-01-06 2008-03-19 Hitachi Global Storage Technologies B. V. Disk unit, magnetic disk unit and information storage unit
US8424081B2 (en) 2006-01-06 2013-04-16 HGST Netherlands B.V. Disk unit, magnetic disk unit and information storage unit

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