US3740720A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method adapted for continually updating information on a magnetic tape
Assignee: International Business Machines Corp
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Filing: 1971-01-25
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Granted: 1973-06-19
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Expires: 1991-01-25
Abstract
Abstract A method capable of continually rewriting or updating data into desired record areas delineated by conventional inter-record-gaps by (1) reading the records to be updated, where m the number of record areas to be updated, (2) moving in a reverse direction or backspacing the tape m + 1 times so as to position the reading and writing heads over a record area external to the m group of record areas, (3) reading the external record area, and (4) writing into the m group of record areas in order to operate the system in a legitimate read-write mode.
Inventors
- 👤 C Swaney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:08
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/12; G11B20/1201; G11B20/1202; G11B20/1205
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
133 words
A method of rewriting or updating data into an m group of record areas on a medium storing a plurality of record areas, the record areas being delineated by conventional inter-record-gaps comprising the steps of: a. reading an m group of record areas by moving the medium in a first direction in relationship to reading and writing means, where m 1, or 2, or 3, . . . or n, b. moving the medium in a direction opposite to the first direction at least m + 1 record areas for positioning the reading and writing means over a first record area external to the m group of record areas, c. reading the first record area, and d. writing data into the m group of record areas in order to update the information therein.
Claim 2
Independent Claim
133 words
A method of rewriting or updating data into an m group of record areas on a medium storing a plurality of record areas, the record areas being delineated by conventional inter-record-gaps comprising the steps of: a. reading an m group of record areas by moving the medium in a first direction in relationship to reading and writing means, where m 1, or 2, or 3, . . . or n, b. moving the medium in a direction opposite to the first direction at least m + 1 record areas for positioning the reading and writing means over a first record area external to the m group of record areas, c. reading the first record area, and d. writing data into the m group of record areas in order to update the information therein.
Claim 3
Dependent Claim
14 words
A method as in claim 1 wherein the moving step comprises a backspacing operation.
Claim 4
Dependent Claim
15 words
A method as in claim 1 wherein the moving step comprises a read backward operation.
Claim 5
Independent Claim
164 words
A method of selectively rewriting or updating data into an m group of record areas on a magnetic tape medium having a plurality of record areas delineated by conventional inter-record-gaps, where m 1, or 2, or 3 . . . or n, comprising the steps of: a. selecting a tape drive system having means for reading and writing onto the magnetic tape medium, b. reading m record areas by moving the magnetic tape medium in a first direction in relationship to the means for reading and writing, c. reversing the magnetic tape medium in a second direction opposite to the first direction over m + 1 record areas so as to position the means for reading and writing over a first record area external to the m group of record areas, d. reading the first record area, and followed by, e. writing data into the m group of record areas in order to selectively update the data in the m group of record areas.
Claim 6
Independent Claim
164 words
A method of selectively rewriting or updating data into an m group of record areas on a magnetic tape medium having a plurality of record areas delineated by conventional inter-record-gaps, where m 1, or 2, or 3 . . . or n, comprising the steps of: a. selecting a tape drive system having means for reading and writing onto the magnetic tape medium, b. reading m record areas by moving the magnetic tape medium in a first direction in relationship to the means for reading and writing, c. reversing the magnetic tape medium in a second direction opposite to the first direction over m + 1 record areas so as to position the means for reading and writing over a first record area external to the m group of record areas, d. reading the first record area, and followed by, e. writing data into the m group of record areas in order to selectively update the data in the m group of record areas.
Claim 7
Dependent Claim
172 words
A method of selectively rewriting or updating data into an m group of record areas on a magnetic tape medium having a plurality of record areas delineated by conventional inter-record-gaps, where m 1, or 2, or 3 . . . or n, as in claim 4 and further comprising the steps of: a. selecting a tape drive system having means for reading, writing, and erasing the magnetic tape medium, the reading, writing, and erasing means being spaced from each other, b. locating a specific inter-record-gap adjacent to the end of the last record area in the m group of record areas, and c. forming the specific inter-record-gap of sufficient length relative to the spacing between the means for reading and writing, and the means for erasing in order to prevent the erasing means from inadvertently destroying data located in a record area adjacent to the specific inter-record-gap and external to the m group of record areas during the method of selectively rewriting or updating data into an m group of record areas.
References Cited (Backward Citations)
US2975407A
Cited
US3533071A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-18 | 1976-12-18 | 1977-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-18 | 1980-12-18 | 1981-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-18 | 1984-12-18 | 1985-06-19 | $7700.00 | Window Closed / Lapsed |