US3751646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Error detection and correction for data processing systems
Assignee: International Business Machines Corp
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Filing: 1971-12-22
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Granted: 1973-08-07
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Expires: 1991-12-22
Abstract
Abstract An error detecting and correcting system is provided for a unit having an essentially subordinate structure, such as a function unit of a computer. Correct output signals are assumed for the unit and, accordingly, check bits are formed as a function of the output signals of the unit. These bits are stored with a control word associated with each operation. As the operation is being executed, the check bits are regenerated from the output signals of the function unit and are subsequently compared with the correct check bits previously stored. Non-concurrence of the check bits indicates that an error may have occurred in the unit.
Inventors
- 👤 H Geng
- 👤 V Goetze
- 👤 J Hajdu
- 👤 P Skuin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:54
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/08; G06F11/10; H; H03; H03M; H03M13/00; H03M13/03; H03M13/05
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
81 words
In an error detection system for a functional unit which responds to information within a data processing system; means for storing at least one check bit indicative of the error free operation of said functional unit in association with said information; means for regenerating the check bits from the output of said functional unit after operating in response to said information; means for comparing the stored check bits with the regenerated check bits thereby detecting the errors indicated by any noncomparison.
Claim 2
Dependent Claim
81 words
In an error detection system for a functional unit which responds to information within a data processing system; means for storing at least one check bit indicative of the error free operation of said functional unit in association with said information; means for regenerating the check bits from the output of said functional unit after operating in response to said information; means for comparing the stored check bits with the regenerated check bits thereby detecting the errors indicated by any noncomparison.
Claim 3
Dependent Claim
30 words
A system in accordance with claim 1, wherein said functional unit is the operation decoder and said information is the operation code of the control of a data processing system.
Claim 4
Dependent Claim
39 words
A system in accordance with claim 2, wherein said means for storing at least one check bit comprises a control word storage where said at least one check bit is stored in a field of the associated control word.
Claim 5
Dependent Claim
37 words
A system in accordance with claim 2, wherein said storage means includes a separate storage for said at least one check bit; means for fetching said check bit(s) together with said operation code acting as an address.
Claim 6
Dependent Claim
79 words
A system according to claim 1, wherein said functional unit has its output lines subdivided into groups, at least one check being provided for each group and the check bits of each group being separately stored in said means for storing a plurality of said regenerating means are provided one for each of said groups and a plurality of said comparison means are provided one for each of said groups so that errors can be detected by said non-comparison.
Claim 7
Dependent Claim
29 words
A system in accordance with claim 3, wherein a parity bit is generated from the control word which includes said at least one check bit and is then stored.
Claim 8
Dependent Claim
32 words
A system in accordance with claim 6, wherein said parity bit is regenerated by said regenerating means from the control word and is compared in said comparison unit said stored parity bit.
Claim 9
Dependent Claim
66 words
A system according to claim 6, wherein the control word has its outputs arranged in groups, a parity bit being provided for each group and being separately stored, a plurality of said regenerating means are provided one for each of said groups and a plurality of said comparison means are provided one for each of said groups so that errors can be detected by said non-comparison.
References Cited (Backward Citations)
US3218612A
Cited
US3231858A
Cited
US3387262A
Cited
US3478313A
Cited
US3531631A
Cited
US3599146A
Cited
US3573728A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |