JPS5637893A - Address change-over unit of programmable read-only memory - Google Patents
Address change-over unit of programmable read-only memoryInfo
- Publication number
- JPS5637893A JPS5637893A JP11031579A JP11031579A JPS5637893A JP S5637893 A JPS5637893 A JP S5637893A JP 11031579 A JP11031579 A JP 11031579A JP 11031579 A JP11031579 A JP 11031579A JP S5637893 A JPS5637893 A JP S5637893A
- Authority
- JP
- Japan
- Prior art keywords
- prom
- control data
- addresses
- area
- write
- 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
Links
Landscapes
- Read Only Memory (AREA)
- For Increasing The Reliability Of Semiconductor Memories (AREA)
- Techniques For Improving Reliability Of Storages (AREA)
Abstract
PURPOSE: To make it possible to write data in a normal area by making an area, where an error is happening, unused by selectively changing over addresses of PROM running into trouble.
CONSTITUTION: When the information volume of control data to be written never surpasses 512B, switch SW is turned on to set the most significant digit bit A0 to "0". Then, nine bits of memory addresses A1WA9 are selectively activated to write control data in PROM by way of data input-output terminals b0Wb7. As a result, the control data are written at addresses 0W511 in area I. In case that there is a fault found in PROM, SW is turned off to set the most significant digit bit A0 of the address to "1" and nine bits A1WA9 are selectively activated to write the control data at addresses 512W1023 in area II of PROM via input-output terminals b0Wb7.
COPYRIGHT: (C)1981,JPO&Japio
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP11031579A JPS5637893A (en) | 1979-08-31 | 1979-08-31 | Address change-over unit of programmable read-only memory |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP11031579A JPS5637893A (en) | 1979-08-31 | 1979-08-31 | Address change-over unit of programmable read-only memory |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5637893A true JPS5637893A (en) | 1981-04-11 |
Family
ID=14532592
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP11031579A Pending JPS5637893A (en) | 1979-08-31 | 1979-08-31 | Address change-over unit of programmable read-only memory |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5637893A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58152226A (en) * | 1982-03-05 | 1983-09-09 | Minolta Camera Co Ltd | Data outputting device of camera accessory |
JPS59135600U (en) * | 1983-02-25 | 1984-09-10 | 株式会社アドバンテスト | Electronic equipment with rewritable non-volatile memory |
JPH0333927A (en) * | 1989-06-29 | 1991-02-14 | Canon Inc | Electronic equipment |
-
1979
- 1979-08-31 JP JP11031579A patent/JPS5637893A/en active Pending
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58152226A (en) * | 1982-03-05 | 1983-09-09 | Minolta Camera Co Ltd | Data outputting device of camera accessory |
JPH0456293B2 (en) * | 1982-03-05 | 1992-09-08 | Minolta Camera Kk | |
JPS59135600U (en) * | 1983-02-25 | 1984-09-10 | 株式会社アドバンテスト | Electronic equipment with rewritable non-volatile memory |
JPH0333927A (en) * | 1989-06-29 | 1991-02-14 | Canon Inc | Electronic equipment |
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