US3760115A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crosspoint error detection in time division multiplex switching systems
Assignee: Postmaster General
•
Filing: 1971-03-22
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Granted: 1973-09-18
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Expires: 1991-03-22
Abstract
Abstract A circuit for detecting the operation of crosspoint switches in a time division multiplex switching system. The crosspoints are coded and when a crosspoint is operated its code is transmitted to a checking circuit that compares the code against a check code and produces an error signal in the event of a discrepancy.
Inventors
- 👤 W Duerdoth
- 👤 C Hughes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:01
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/02; H04J; H04J3/00; H04J3/02; H04J3/14; H04Q11/04
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
185 words
A time division muliplex communication system comprising in combination: 1. at least one switching means comprising a plurality of crosspoint switches, 2. storage means for receiving and storing the addresses of crosspoint switches together with additional crosspoint switch operation check information, 3. each said address comprising a series of binary coded digits and said check information comprising at least one further binary coded digit, 4. means including output leads from said storage means to said crosspoint switches for applying said stored addresses and said check information to said crosspoint switches to activate an addressed crosspoint switch, and 5. an error detection circuit for detecting an error in the operation of an addressed cross-point switch, said circuit comprising A. gate means connected to the outputs of respective crosspoint switches for indicating that the associated crosspoint switch is in an operated condition, and B. means connected to said gate means and connected to receive said check information from said storage means for indicating an error when the output of said gate means reflects operation inconsistent with the activation of the crosspoint switch indicated by said check information.
Claim 2
Dependent Claim
185 words
A time division muliplex communication system comprising in combination: 1. at least one switching means comprising a plurality of crosspoint switches, 2. storage means for receiving and storing the addresses of crosspoint switches together with additional crosspoint switch operation check information, 3. each said address comprising a series of binary coded digits and said check information comprising at least one further binary coded digit, 4. means including output leads from said storage means to said crosspoint switches for applying said stored addresses and said check information to said crosspoint switches to activate an addressed crosspoint switch, and 5. an error detection circuit for detecting an error in the operation of an addressed cross-point switch, said circuit comprising A. gate means connected to the outputs of respective crosspoint switches for indicating that the associated crosspoint switch is in an operated condition, and B. means connected to said gate means and connected to receive said check information from said storage means for indicating an error when the output of said gate means reflects operation inconsistent with the activation of the crosspoint switch indicated by said check information.
Claim 3
Dependent Claim
19 words
storage means for receiving and storing the addresses of crosspoint switches together with additional crosspoint switch operation check information,
Claim 4
Dependent Claim
19 words
storage means for receiving and storing the addresses of crosspoint switches together with additional crosspoint switch operation check information,
Claim 5
Dependent Claim
84 words
A system as claimed in claim 1, said gate means (A) comprising first gate circuits to which the outputs of said crosspoint switches are connected as inputs, and said means (B) comprises second gate circuits to each of which the outputs of one of the first gate circuits is connected as an input, each of said second gate circuits also having at least one further input connected to receive said check information from said storage means simultaneously with the operation of the crosspoint switch.
Claim 6
Dependent Claim
33 words
A system as claimed in claim 1, further comprising means for storing in said storage means said additional check information at the channel time at which the crosspoint switch identified thereby is operated.
Claim 7
Dependent Claim
22 words
each said address comprising a series of binary coded digits and said check information comprising at least one further binary coded digit,
Claim 8
Dependent Claim
22 words
each said address comprising a series of binary coded digits and said check information comprising at least one further binary coded digit,
Claim 9
Dependent Claim
32 words
means including output leads from said storage means to said crosspoint switches for applying said stored addresses and said check information to said crosspoint switches to activate an addressed crosspoint switch, and
Claim 10
Dependent Claim
32 words
means including output leads from said storage means to said crosspoint switches for applying said stored addresses and said check information to said crosspoint switches to activate an addressed crosspoint switch, and
Claim 11
Dependent Claim
87 words
an error detection circuit for detecting an error in the operation of an addressed cross-point switch, said circuit comprising A. gate means connected to the outputs of respective crosspoint switches for indicating that the associated crosspoint switch is in an operated condition, and B. means connected to said gate means and connected to receive said check information from said storage means for indicating an error when the output of said gate means reflects operation inconsistent with the activation of the crosspoint switch indicated by said check information.
Claim 12
Dependent Claim
87 words
an error detection circuit for detecting an error in the operation of an addressed cross-point switch, said circuit comprising A. gate means connected to the outputs of respective crosspoint switches for indicating that the associated crosspoint switch is in an operated condition, and B. means connected to said gate means and connected to receive said check information from said storage means for indicating an error when the output of said gate means reflects operation inconsistent with the activation of the crosspoint switch indicated by said check information.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |