초록 ▼

A data processing system includes a central processing complex consisting of one or more processor units, each of the processor units having one or more input/output channels, a transmission medium connected to each of the input/output channels, and one or more peripheral device controllers such as

A data processing system includes a central processing complex consisting of one or more processor units, each of the processor units having one or more input/output channels, a transmission medium connected to each of the input/output channels, and one or more peripheral device controllers such as for controlling one or more direct access storage devices (DASD). In systems having more than one input/output channels, it is common to include a switching mechanism connected between the input/output channels and the control devices for enabling connection between one of a number of controllers and one of a number of channels. Each control device will include an automatic frame transmission function which includes apparatus and method for controlling transmission of frames of information between the control device and the channel. A queue of reconnection requests is constructed and a state machine controls the queue. For example, the state machine reads the queue, loads and sends frames from the controller to the channel, manages a redrive timer and automatically redrives or terminates automatic frame transmission processing depending on system parameters and responses received from the channel or from another controller in controller to controller transmissions.

대표청구항 ▼

[ What is claimed is:] [1.] A data processing system, comprising:one or more processing units, each having one or more input/output channel units;one or more input/output control units, each controlling one or more peripheral devices; anda information transmission medium connected to each of said ch

[ What is claimed is:] [1.] A data processing system, comprising:one or more processing units, each having one or more input/output channel units;one or more input/output control units, each controlling one or more peripheral devices; anda information transmission medium connected to each of said channel units and to each of said control units;each of said control units comprising an automatic frame transmission means for controlling connection requests originating in said control units to send information to one of said channel units, said automatic frame transmission means comprising;means for storing data relating to a connection request;means for maintaining a queue of connection requests;means for adding additional entries containing addresses of additional channel units to said queue without interrupting the operation of said processing system;means for managing said connection requests based on information in said queue; andmeans for retrying connection requests to a same channel unit or to a different channel unit following an unsuccessful connection attempt.