JPS6436345A - Memory protecting system - Google Patents
Memory protecting systemInfo
- Publication number
- JPS6436345A JPS6436345A JP62191709A JP19170987A JPS6436345A JP S6436345 A JPS6436345 A JP S6436345A JP 62191709 A JP62191709 A JP 62191709A JP 19170987 A JP19170987 A JP 19170987A JP S6436345 A JPS6436345 A JP S6436345A
- Authority
- JP
- Japan
- Prior art keywords
- processing unit
- central processing
- protect
- state
- status signal
- 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
- Storage Device Security (AREA)
- Debugging And Monitoring (AREA)
Abstract
PURPOSE:To surely perform memory protect check, by providing a protect pattern corresponding to the status signal of a central processing unit in a memory device, and performing protect check fitted for the operation of the central processing unit. CONSTITUTION:The titled system is constituted of the central processing unit 10 which outputs the status signal to show the operating states of the readout of a program, that of data, or the write of the data and also performs every kind of operation, the memory device 20 to store a protect pattern corresponding to every state, a selection circuit 50 which makes access to the address of the memory device 20 corresponding to the state of the central processing unit 10 and selects the protect pattern at every state, and a detection circuit 80 which controls the operation of the central processing unit 10 by monitoring the validity of the operation of the central processing unit 10 based on the status signal and the address made access at the selection circuit 50. In such a way, it is possible to perform memory protection appropriately corresponding to the operating state of the central processing unit 10.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62191709A JPS6436345A (en) | 1987-07-31 | 1987-07-31 | Memory protecting system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62191709A JPS6436345A (en) | 1987-07-31 | 1987-07-31 | Memory protecting system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS6436345A true JPS6436345A (en) | 1989-02-07 |
Family
ID=16279173
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP62191709A Pending JPS6436345A (en) | 1987-07-31 | 1987-07-31 | Memory protecting system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6436345A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04117541A (en) * | 1990-09-07 | 1992-04-17 | Nec Corp | Memory controller |
-
1987
- 1987-07-31 JP JP62191709A patent/JPS6436345A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04117541A (en) * | 1990-09-07 | 1992-04-17 | Nec Corp | Memory controller |
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