EP0213534A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
IC card
Assignee: Casio Computer Co Ltd
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Filing: 1986-08-18
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Granted: —
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Expires: 2006-08-18
Abstract
Abstract When data is written in a predetermined memory area of a data memory (65) in an IC card (ll), a comparator (63) checks whether the data before writing and data actually written in the data memory (65) coincide. In the event of non-coincidence of the compared data, the data to be written is written in a different memory area of the data memory (65).
Inventors
- 👤 Shigeyuki Pat Dpt D Div Hamura R&D Center Kawana
- 👤 Harumi Pat Dpt D Div Hamura R&D Center Nakano
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 03:32
CPC Classifications
G; G07; G07F; G07F7/00; G07F7/08; G07F7/0806; G07F7/0833; G07F7/084; G06; G06F; G06F11/00; G06F11/07; G06F11/08; G06Q; G06Q20/00; G06Q20/30; G06Q20/34; G06Q20/341; G07F7/10; G07F7/1008; G11; G11C; G11C29/00; G11C29/70
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
128 words
An IC card characterized by comprising: data storing means (65) having a plurality of blocks (Ml, M2) for storing at least secret data in each said block; means (58) for designating the address of a desired memory area of said data storing means to effect writing or reading of data with respect to said designated address memory area; means (63) for detecting whether data is correctly written in the memory area of the address designated by said address designating means; and control means (56) for functioning at the time of detection by said detecting means (63) of incorrect writing of data in said data storing means to let said address designating means (58) designate a different block and let said data be written again in said other block.
Claim 2
Dependent Claim
128 words
An IC card characterized by comprising: data storing means (65) having a plurality of blocks (Ml, M2) for storing at least secret data in each said block; means (58) for designating the address of a desired memory area of said data storing means to effect writing or reading of data with respect to said designated address memory area; means (63) for detecting whether data is correctly written in the memory area of the address designated by said address designating means; and control means (56) for functioning at the time of detection by said detecting means (63) of incorrect writing of data in said data storing means to let said address designating means (58) designate a different block and let said data be written again in said other block.
Claim 3
Dependent Claim
72 words
An IC card according to claim l, characterized in that each block (Ml, M2) of said data storing means (65) has a memory area for storing flag data, and said IC card further comprises means for writing, in response to the detection by said detecting means of the failure of correct writing of data, of flag data representing the incapability of the memory area in the flag area corresponding to said data.
Claim 4
Dependent Claim
43 words
An IC card according to claim l, characterized in that said detecting means includes means (63) for checking whether data to be written in said data storing means (65) and data written in a memory area designated by said address designating means coincide.
Claim 5
Dependent Claim
72 words
An IC card according to claim 3, characterized in that said detecting means (56) further includes means (56b) for calculating a check sum of the data to be written in said storing means (65), said check sum being written together data in said storing means (65), and said checking means compares the check sum data of the data before being written in said storing means and the already written check sum data.
Claim 6
Dependent Claim
31 words
An IC card according to claim l, characterized in that secret data stored in said data storing means (65) is identification data for checking the validity of the IC card holder.
Claim 7
Dependent Claim
28 words
An IC card according to claim 5, characterized in that said identification data is supplied from a card terminal (4l) to which said IC card (ll) is attached.
Claim 8
Dependent Claim
18 words
An IC card according to claim 2, characterized in that said data storing means (65) comprise an EPROM.
References Cited (Backward Citations)
No citation records indexed.
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