JPS5746394A - Data rom mounting method - Google Patents

Data rom mounting method

Info

Publication number
JPS5746394A
JPS5746394A JP12239780A JP12239780A JPS5746394A JP S5746394 A JPS5746394 A JP S5746394A JP 12239780 A JP12239780 A JP 12239780A JP 12239780 A JP12239780 A JP 12239780A JP S5746394 A JPS5746394 A JP S5746394A
Authority
JP
Japan
Prior art keywords
turned
rom1
spare
rom2
power supply
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
JP12239780A
Other languages
Japanese (ja)
Inventor
Hiroyuki Tanaka
Hideyuki Koike
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.)
Hitachi Ltd
Nippon Telegraph and Telephone Corp
Original Assignee
Hitachi Ltd
Nippon Telegraph and Telephone Corp
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 Hitachi Ltd, Nippon Telegraph and Telephone Corp filed Critical Hitachi Ltd
Priority to JP12239780A priority Critical patent/JPS5746394A/en
Publication of JPS5746394A publication Critical patent/JPS5746394A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11C—STATIC STORES
    • G11C17/00—Read-only memories programmable only once; Semi-permanent stores, e.g. manually-replaceable information cards

Landscapes

  • Read Only Memory (AREA)
  • For Increasing The Reliability Of Semiconductor Memories (AREA)

Abstract

PURPOSE:To facilitate an easy exchange of an ROM, by providing a pair of spare and using ROM sockets storing the station data to a front panel, and a changeover switch and a switching circuit. CONSTITUTION:In case a change is given to the station data, etc. and the contents of a using ROM1 has to be changed, a spare ROM2 is mounted on a front panel 14. Then a switch SW is turned toward the spare side, and accordingly NAND gates 7 and 8 open to set a filip-flop 9. As a result, a transistor (TR)13 is turned on to apply the power supply to the ROM2. On the contrary, a TR12 is turned off to break the power supply of the ROM1. Furthermore tri-state buffers 5 and 6 are turned on; while tri-state buffers 3 and 4 are turned off. Thus the separation of the ROM1 is made possible.
JP12239780A 1980-09-05 1980-09-05 Data rom mounting method Pending JPS5746394A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP12239780A JPS5746394A (en) 1980-09-05 1980-09-05 Data rom mounting method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP12239780A JPS5746394A (en) 1980-09-05 1980-09-05 Data rom mounting method

Publications (1)

Publication Number Publication Date
JPS5746394A true JPS5746394A (en) 1982-03-16

Family

ID=14834775

Family Applications (1)

Application Number Title Priority Date Filing Date
JP12239780A Pending JPS5746394A (en) 1980-09-05 1980-09-05 Data rom mounting method

Country Status (1)

Country Link
JP (1) JPS5746394A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7020301B2 (en) 2001-11-05 2006-03-28 Matsushita Electric Industrial Co., Ltd. Loudspeaker
JP2008118218A (en) * 2006-10-31 2008-05-22 Sanyo Electric Co Ltd Electroacoustic transducer
JP2008118217A (en) * 2006-10-31 2008-05-22 Sanyo Electric Co Ltd Electroacoustic transducer

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7020301B2 (en) 2001-11-05 2006-03-28 Matsushita Electric Industrial Co., Ltd. Loudspeaker
JP2008118218A (en) * 2006-10-31 2008-05-22 Sanyo Electric Co Ltd Electroacoustic transducer
JP2008118217A (en) * 2006-10-31 2008-05-22 Sanyo Electric Co Ltd Electroacoustic transducer

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