JPH0373013B2 - - Google Patents

Info

Publication number
JPH0373013B2
JPH0373013B2 JP60212541A JP21254185A JPH0373013B2 JP H0373013 B2 JPH0373013 B2 JP H0373013B2 JP 60212541 A JP60212541 A JP 60212541A JP 21254185 A JP21254185 A JP 21254185A JP H0373013 B2 JPH0373013 B2 JP H0373013B2
Authority
JP
Japan
Prior art keywords
code
input
counter
storage device
outside
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.)
Expired - Lifetime
Application number
JP60212541A
Other languages
Japanese (ja)
Other versions
JPS6273350A (en
Inventor
Eisuke Ito
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.)
Toshiba Corp
Original Assignee
Tokyo Shibaura 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 Tokyo Shibaura Electric Co Ltd filed Critical Tokyo Shibaura Electric Co Ltd
Priority to JP60212541A priority Critical patent/JPS6273350A/en
Publication of JPS6273350A publication Critical patent/JPS6273350A/en
Publication of JPH0373013B2 publication Critical patent/JPH0373013B2/ja
Granted legal-status Critical Current

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  • Storage Device Security (AREA)

Description

【発明の詳細な説明】 〔発明の技術分野〕 本発明は予め設定されたID(Identify)コード
と、外部から入力されたIDコードとを比較し、
両コードが一致した場合にのみアクテイブになる
記憶装置に関する。
[Detailed Description of the Invention] [Technical Field of the Invention] The present invention compares a preset ID (Identify) code with an externally input ID code,
It relates to a storage device that becomes active only when both codes match.

〔発明の技術的背景とその問題点〕[Technical background of the invention and its problems]

従来の記憶装置は、外部からのアクセスに対
し、そのアクセスが正当か不当かを判断する術を
もたず、外部のアクセスに無条件に反応する。ま
たIDコードをもつ記憶装置でも、IDコードを変
えて何度でも試行すれば、有限の回数でIDコー
ドが解読される。
Conventional storage devices have no way of determining whether an access from the outside is legitimate or illegal, and react unconditionally to the access from the outside. Furthermore, even with storage devices that have an ID code, if you change the ID code and try as many times as you like, the ID code can be decoded within a finite number of times.

即ち従来の記憶装置では、その記憶内容を保護
する手段をもたないため、その保護のために、そ
の記憶装置を使うシステム側で保護の手段をとつ
ている。例えば磁気カードの暗証番号等では、連
続して3回暗証を間違えると、カードを返却しな
い。しかし2回試行し、別のカードを入れ、再度
試行を繰り返すことで、暗証番号の解読は可能で
ある。これは、記憶している磁気カード側に判断
能力がないためである。
That is, since conventional storage devices do not have means to protect the stored contents, the system using the storage device takes measures to protect the contents. For example, with a magnetic card PIN, if you enter the wrong PIN three times in a row, the card will not be returned. However, by trying twice, inserting another card, and trying again, it is possible to decipher the PIN. This is because the magnetic card that stores the information does not have the ability to make decisions.

〔発明の目的〕[Purpose of the invention]

本発明は上記実情に鑑みてなされたもので、従
来問題であつた記憶素子側の判断能力、即ちID
コードを内部にもつ記憶装置において、IDコー
ドの比較器と、IDコードが連続して異なる場合
動作を禁止する機能をもつ記憶装置を提供しよう
とするものである。
The present invention has been made in view of the above-mentioned circumstances.
The present invention aims to provide a storage device having a code internally, which has an ID code comparator and a function of prohibiting operation when the ID codes are different in succession.

〔発明の概要〕[Summary of the invention]

本発明は、第3者がIDコードを調べる目的で
種々のIDコードを入力した場合、その入力回数
がある決められた回数をこえた場合、記憶装置の
動作を禁止する信号を発生する。例えばRAMに
おいて、同一アドレスでチツプイネーブル信号が
n回入つた場合、n回目以降はすべての入力を無
効にするようにしたものである。
According to the present invention, when a third party inputs various ID codes for the purpose of checking the ID codes, if the number of inputs exceeds a predetermined number, a signal is generated to inhibit the operation of the storage device. For example, in a RAM, if a chip enable signal is input n times at the same address, all inputs are invalidated after the nth time.

〔発明の実施例〕[Embodiments of the invention]

以下図面を参照して本発明の一実施例を説明す
る。第1図は同実施例を説明するための回路図で
あり、1はアドレス遷移検出回路で、アドレス入
力A1〜ANが変わつたことを検出し、N進カウン
タ2にクリア信号を与える。N進カウンタ2は設
定数カウントすると禁止信号を出力する。アンド
回路3はチツプイネーブル信号とカウンタ2
の出力を入力とし、内部回路つまり記憶装置の制
御回路へ信号を与える。
An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram for explaining the same embodiment. Reference numeral 1 denotes an address transition detection circuit, which detects changes in address inputs A 1 to A N and provides a clear signal to an N-ary counter 2. In FIG. When the N-adic counter 2 counts the set number, it outputs a prohibition signal. AND circuit 3 connects the chip enable signal and counter 2
The output of the controller is input, and a signal is given to the internal circuit, that is, the control circuit of the storage device.

第2図は正常はアクセス(通常の読み出し)の
場合を示すタイムチヤート、第3図はIDコード
を解読しようとするアクセス(IDコードをさが
そうとする場合)を示すタイムチヤートである。
FIG. 2 is a time chart showing a normal access (normal reading), and FIG. 3 is a time chart showing an access attempting to decode an ID code (trying to find an ID code).

第2図の場合、信号の立ち下がりでIDコー
ド(Din)が認識される。つまりカウンタ2の出
力は最初“1”なので、信号が“0”に変化
すると、カウンタ3の出力は“0”に変化してイ
ネーブル状態となり、データ(Dout)が読み出
される。
In the case of FIG. 2, the ID code (Din) is recognized at the falling edge of the signal. That is, since the output of the counter 2 is initially "1", when the signal changes to "0", the output of the counter 3 changes to "0" and becomes enabled, and data (Dout) is read out.

一方第3図のように、同一アドレスに対して複
数回読み出し動作を行なおうとする場合、信号
CEによりカウンタ2で読み出し回数をカウント
し、設定カウント数をこえた場合にはカウンタ2
の出力が“0”になる。これが“0”になると、
信号が“1”から“0”に変化しても、アン
ド回路3の出力は常に“0”になりつきりになり
(“1”から“0”への変化がない)、IDコードの
入力が受けつけられなくなる(無効になる)。な
おアドレスA1〜ANが変われば、その都度カウン
タ2はクリアされ、カウンタ2の出力は“1”に
なるので、正常の読み出し動作に影響を与えない
ものである。
On the other hand, as shown in Figure 3, when attempting to read the same address multiple times, the signal
Counter 2 counts the number of readings by CE, and if it exceeds the set count number, counter 2
The output becomes “0”. When this becomes “0”,
Even if the signal changes from "1" to "0", the output of AND circuit 3 will always be "0" (there will be no change from "1" to "0"), and the ID code will not be input. will no longer be accepted (become invalid). Note that each time the addresses A 1 to A N change, the counter 2 is cleared and the output of the counter 2 becomes "1", so that it does not affect the normal read operation.

〔発明の効果〕〔Effect of the invention〕

以上説明した如く本発明によれば、記憶装置に
ID識別部を設け、外部からの解読操作に対する
保護機能をもたせることで、記憶内容の保護、機
密が保たれるものである。
As explained above, according to the present invention, the storage device
By providing an ID identification section and providing a protection function against decoding operations from outside, the storage contents are protected and kept confidential.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明の一実施例を説明するための回
路図、第2図、第3図は同回路の動作を示すタイ
ムチヤートである。 1……アドレス遷移検出回路、2……N進カウ
ンタ、3……アンド回路。
FIG. 1 is a circuit diagram for explaining one embodiment of the present invention, and FIGS. 2 and 3 are time charts showing the operation of the same circuit. 1... Address transition detection circuit, 2... N-ary counter, 3... AND circuit.

Claims (1)

【特許請求の範囲】[Claims] 1 予め設定されたIDコードと、外部から入力
されたIDコードとを比較し、両IDコードが一致
した場合にのみアクテイブになる記憶装置におい
て、同一アドレス状態で外部から入力されるID
コードの入力回数をカウントする手段と、この手
段のカウント値が設定数をこえた場合、外部から
のIDコードの入力を無効にする手段とを具備し
たことを特徴とする記憶装置。
1 Compare the preset ID code and the ID code input from the outside, and activate only when both ID codes match.In the storage device, the ID input from the outside at the same address state
A storage device comprising means for counting the number of times a code is input, and means for disabling input of an ID code from the outside when the count value of the means exceeds a set number.
JP60212541A 1985-09-27 1985-09-27 Storage device Granted JPS6273350A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP60212541A JPS6273350A (en) 1985-09-27 1985-09-27 Storage device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP60212541A JPS6273350A (en) 1985-09-27 1985-09-27 Storage device

Publications (2)

Publication Number Publication Date
JPS6273350A JPS6273350A (en) 1987-04-04
JPH0373013B2 true JPH0373013B2 (en) 1991-11-20

Family

ID=16624383

Family Applications (1)

Application Number Title Priority Date Filing Date
JP60212541A Granted JPS6273350A (en) 1985-09-27 1985-09-27 Storage device

Country Status (1)

Country Link
JP (1) JPS6273350A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0476749A (en) * 1990-07-19 1992-03-11 Toshiba Corp Security circuit

Also Published As

Publication number Publication date
JPS6273350A (en) 1987-04-04

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