US3801962A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Communication mechanism for data transfer and control between data processing systems and subsystems
Assignee: International Business Machines Corp
•
Filing: 1972-12-29
•
Granted: 1974-04-02
•
Expires: 1992-12-29
Abstract
Abstract Apparatus for establishing and maintaining communication between a number of different types of subsystems of a data processing system. The apparatus contains elements which are subsettable with respect to the various functions which are performed depending upon the characteristics of each of the subsystems which are connected together. One function is that of attaching process control devices to a central processing unit. These devices are characterized by having simple interfaces, by involving non-terminating operations, by having high storage access rates and by time dependencies. A further function is that of inter-CPU signalling involving the transfer of small amounts of information. A further function is that of sharing main storage between a CPU and a subsystem element. The communication apparatus is comprised of two separate and functionally independent logical elements. The first is an external main storage adapter which performs the function of sharing storage between the central processing unit and a subsystem element. The second logical unit is the control adapter which provides the physical and logical connection between the subsystem units. The control adapter attaches to a control interface which contains a polling mechanism, a selection mechanism, a general bus, and several interlocked communication tag lines. A control transfer sequence is defined by the interface such that each attached subsystem may initiate communication with any other attached subsystem. A polling mechanism allocates temporary control of the interface to a unit desiring to initiate communication. A selection mechanism allows selective subsystem-to-subsystem communication.
Inventors
- 👤 B Moore
- 👤 C Thorn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:33
CPC Classifications
G; G06; G06F; G06F13/00; G06F13/14; G06F13/20; G06F13/38
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
83 words
A data processing system comprising: a plurality of subsystems; a control transfer interface; a data transfer interface logically independent of said control transfer interface; means for connecting said subsystems to said control interface in a multi-dropped closed loop; means for connecting said subsystems to said data transfer interface point-to-point; a polling mechanism in each subsystem and associated with said control transfer interface for allocating temporary control of said control interface to A subsystem desiring to initiate data transfer over said data transfer interface.
Claim 2
Dependent Claim
83 words
A data processing system comprising: a plurality of subsystems; a control transfer interface; a data transfer interface logically independent of said control transfer interface; means for connecting said subsystems to said control interface in a multi-dropped closed loop; means for connecting said subsystems to said data transfer interface point-to-point; a polling mechanism in each subsystem and associated with said control transfer interface for allocating temporary control of said control interface to A subsystem desiring to initiate data transfer over said data transfer interface.
Claim 3
Dependent Claim
118 words
A data processing system comprising: a plurality of subsystems; a control transfer interface; a data transfer interface; means for connecting said subsystems to said control interface in a multi-dropped closed loop; means for connecting said subsystems to said data transfer interface point-to-point; a polling mechanism in each subsystem and associated with said control transfer interface for allocating temporary control of said control interface to a predetermined subsystem desiring to initiate data transfer over said data transfer interface, and means in said predetermined subsystem for sequencing said control transfer interface to effect transfer of program specifiable control initiating order code information and associated return transfer of either acceptance or specific plural bit exception status indications to said predetermined subsystem.
Claim 4
Dependent Claim
118 words
A data processing system comprising: a plurality of subsystems; a control transfer interface; a data transfer interface; means for connecting said subsystems to said control interface in a multi-dropped closed loop; means for connecting said subsystems to said data transfer interface point-to-point; a polling mechanism in each subsystem and associated with said control transfer interface for allocating temporary control of said control interface to a predetermined subsystem desiring to initiate data transfer over said data transfer interface, and means in said predetermined subsystem for sequencing said control transfer interface to effect transfer of program specifiable control initiating order code information and associated return transfer of either acceptance or specific plural bit exception status indications to said predetermined subsystem.
Claim 5
Dependent Claim
146 words
Apparatus for establishing and maintaining communication between a number of different types of subsystems in a data processing system comprising: a control interface including information sources and tag control lines interconnecting said subsystems in a multi-dropped closed loop; polling means associated with each subsystem interacting with said tag control lines of said control interface for relegating to a particular subsystem the logical state of the master subsystem, in a master/slave relationship with others of said subsystems; selection means in said particular subsystem associated with said control interface tag control lines for initiating a control transfer sequence over said control interface, to thereby prepare one of said slave subsystems to send or receive data to or from said master subsystem; an external main storage interface interconnecting said subsystems point-to-point; and means in said particular subsystem for initiating a data transfer sequence over said external main storage interface.
Claim 6
Dependent Claim
146 words
Apparatus for establishing and maintaining communication between a number of different types of subsystems in a data processing system comprising: a control interface including information sources and tag control lines interconnecting said subsystems in a multi-dropped closed loop; polling means associated with each subsystem interacting with said tag control lines of said control interface for relegating to a particular subsystem the logical state of the master subsystem, in a master/slave relationship with others of said subsystems; selection means in said particular subsystem associated with said control interface tag control lines for initiating a control transfer sequence over said control interface, to thereby prepare one of said slave subsystems to send or receive data to or from said master subsystem; an external main storage interface interconnecting said subsystems point-to-point; and means in said particular subsystem for initiating a data transfer sequence over said external main storage interface.
Claim 7
Dependent Claim
144 words
Apparatus for establishing and maintaining communication between a number of different types of subsystems in a data processing system comprising: a control interface including information sources and tag control lines interconnecting said subsystems in a multi-dropped closed loop; selection means in a particular subsystem associated with said control interface for initiating a control transfer sequence to transfer control information over said information sources of said control interface, to thereby select and prepare one of said subsystems to send or receive data to or from said particular subsystem; an external main storage interface interconnecting said subsystems point-to-point; means for initiating a data transfer sequence over said external main storage interface; and a polling mechanism associated with said tag control lines for allocating temporary control of said control interface to said particular subsystem, whereby said particular subsystem may initiate communication with said one of said subsystems.
Claim 8
Dependent Claim
144 words
Apparatus for establishing and maintaining communication between a number of different types of subsystems in a data processing system comprising: a control interface including information sources and tag control lines interconnecting said subsystems in a multi-dropped closed loop; selection means in a particular subsystem associated with said control interface for initiating a control transfer sequence to transfer control information over said information sources of said control interface, to thereby select and prepare one of said subsystems to send or receive data to or from said particular subsystem; an external main storage interface interconnecting said subsystems point-to-point; means for initiating a data transfer sequence over said external main storage interface; and a polling mechanism associated with said tag control lines for allocating temporary control of said control interface to said particular subsystem, whereby said particular subsystem may initiate communication with said one of said subsystems.
References Cited (Backward Citations)
US3673576A
Cited
US3714635A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |