US3823256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data switching system
Assignee: US Philips Corp
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Filing: 1973-01-02
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Granted: 1974-07-09
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Expires: 1993-01-02
Abstract
Abstract A description is given of a data switching system for switching direct connections between TELEX lines by way of a central processor. The system configuration of a message switching system is used as a basis. The communication lines are connected to communication units which send request signals to the central processor when a character is received or transmitted. Registers of the central store are permanently associated with the communication lines. In the register of the receive line the address of the register of the send line is stored. The latter register comprises a number of character locations for storing characters. In reaction to the request signals, the central processor transfers the characters from the communication unit to the register of the send line or conversely.
Inventors
- 👤 R Wittebol
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:04
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/50; H04L12/52
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
298 words
A data switching system for establishing data signal communication connections between receive lines through which the data signals are received and send lines through which data is transmitted, comprising communication unit means connected to said receive lines and said send lines for providing a request signal in response to the reception of a given quantity of data (a character) and after transmission of a character, a central processor connected to said communication units for successively granting the communication units which send a request signal access to the control store for transferring a character between the communication unit and the central store, an incoming and an outgoing line register of the central store being permanently associated with each of said receive lines and send lines, respectively, first addressing means responsive to a connection between a receive line and a send line for storing the address of the outgoing line register in the incoming line register of the central store, the outgoing line register comprising a number of character positions for storing characters, the central processor further comprising means responsive to a request signal originating from the communication unit connected to the receive lines for reading the contents of the incoming line register of the connection and for subsequently selecting the outgoing line register whose address is specified by the contents of the incoming line register and for subsequently storing the received character in a character location of the outgoing line register, the central processor further comprising means responsive to a request signal originating from the communication unit connected to the transmit lines for reading the contents of the outgoing line register of the connection and for subsequently transferring a character from a character location of the outgoing line register to the communication unit from which the request signal originates.
Claim 2
Dependent Claim
298 words
A data switching system for establishing data signal communication connections between receive lines through which the data signals are received and send lines through which data is transmitted, comprising communication unit means connected to said receive lines and said send lines for providing a request signal in response to the reception of a given quantity of data (a character) and after transmission of a character, a central processor connected to said communication units for successively granting the communication units which send a request signal access to the control store for transferring a character between the communication unit and the central store, an incoming and an outgoing line register of the central store being permanently associated with each of said receive lines and send lines, respectively, first addressing means responsive to a connection between a receive line and a send line for storing the address of the outgoing line register in the incoming line register of the central store, the outgoing line register comprising a number of character positions for storing characters, the central processor further comprising means responsive to a request signal originating from the communication unit connected to the receive lines for reading the contents of the incoming line register of the connection and for subsequently selecting the outgoing line register whose address is specified by the contents of the incoming line register and for subsequently storing the received character in a character location of the outgoing line register, the central processor further comprising means responsive to a request signal originating from the communication unit connected to the transmit lines for reading the contents of the outgoing line register of the connection and for subsequently transferring a character from a character location of the outgoing line register to the communication unit from which the request signal originates.
Claim 3
Dependent Claim
230 words
A data switching system as claimed in claim 1, wherein an incoming line register comprises one storage location of the central store, an outgoing line register comprising two storage locations (words) of the central store, the address of the second storage location being stored in the first storage location of the outgoing line register, the central processor further comprising means responsive to reading the contents of the incoming line register of a connection for calculating the address of the second storage location of the outgoing line register from the address specified by the contents of the incoming line register and for deducing this address from the contents of the first word of the outgoing line register, and for subsequently storing the received character in a character location of the second storage location of the outgoing line register, the central processor further comprising means responsive to a request signal originating from the outgoing side of a connection by reading the contents of the first storage location of the outgoing line register of the connection and for subsequently reading the contents of the storage location whose address is specified by the contents of the first storage location of the outgoing line register, and for finally transferring a character from a character location of the second storage location of the outgoing line register to the communication unit from which the request signal originates.
Claim 4
Dependent Claim
118 words
Data switching systems as claimed in claim 2, wherein in an incoming line register of a connection a character address is stored which specifies a character location of the outgoing line register of the connection, the central processor further comprising means responsive to reading the contents of an incoming line register for adding a constant (-1) to the character address, the first storage location of an outgoing line register of a connection containing a character address which specifies the character location of the second storage location of the outgoing line register, the central processor, after having read the contents of the first storage location of the outgoing line register, adding the (said) constant (-1) to the character address.
Claim 5
Dependent Claim
104 words
Data switching systems as claimed in claim 3, wherein in the first storage location of the outgoing line register of a connection a number is stored which specifies the number of characters of the second storage location of the outgoing line register which have not yet been transmitted, the central processor comprising means for adding, after having read the contents of the first storage location, a constant (+1) to the number when a character is transferred to the second storage location, and adding the (said) constant of opposed sign (- 1) to the number when a character is transferred from the second storage location.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-08 | 1978-01-07 | 1978-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-08 | 1982-01-07 | 1982-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-08 | 1986-01-07 | 1986-07-09 | $7700.00 | Window Closed / Lapsed |