公开(公告)号：GB2491436B

公开(公告)日：2013-05-15

申请号：GB201206680

申请日：2012-04-17

Applicant: IBM

Inventor： CASPER DANIEL FRANCIS ,  FLANAGAN JOHN R ,  BUBB CLINTON

IPC: G06F13/12 ,  G06F13/38 ,  G06F13/42 ,  G06F21/60

Abstract: A computer program product is provided for performing a method including: obtaining information relating to an I/O operation at a channel subsystem in a host computer system; generating at least one address control word (ACW) in the local channel memory specifying one or more host memory locations for transfer of data between the host and a control unit and including at least one ACW error checking field; generating an address control structure specifying a location in the local channel memory of a corresponding ACW and including at least one address control structure error checking field; receiving a data transfer request from the network interface that includes the addressing information; comparing the at least one ACW error checking field to the at least one address control structure error checking field; and, responsive to the fields matching, routing the data transfer request to the host memory location specified in the corresponding ACW.

公开(公告)号：GB2491440A

公开(公告)日：2012-12-05

申请号：GB201206684

申请日：2012-04-17

Applicant: IBM

Inventor： CASPER DANIEL FRANCIS ,  FLANAGAN JOHN R ,  BUBB CLINTON ,  BENDER CARL ALFRED

IPC: G06F13/12

Abstract: A method for performing an input/output (I/O) operation between a host computer (102) and control-unit (118) comprises obtaining information about the I/O operation from a channel subsystem (128) in the host system, the channel having a local processor and memory. An Address Control Word (ACW) (Fig 11) is generated and specifying the memory location and having a data discard field (264, Fig 11). An address control structure (Fig 5) for each data transfer in the I/O operation is generated and forwarded to the network interface between the channel subsystem and I/O device and specifies a location in the local memory of the ACW. On receipt of an I/O command message via the network a data transfer request from the network interface is issued and includes addressing information and the corresponding ACW is accessed retrieved and used to route the data transfer request to the host memory (106) specified in the ACW. In response to an error during the accessing or the routing, the transfer is discarded and the data discard field is configured to instruct the channel to discard any subsequent data transfer requests associated with the ACW.

公开(公告)号：DE69029643T2

公开(公告)日：1997-07-17

申请号：DE69029643

申请日：1990-10-06

Applicant: IBM

Inventor： CASPER DANIEL FRANCIS ,  FLANAGAN JOHN RICHARD ,  GREGG THOMAS ANTHONY ,  KALOS MATTHEW JOSEPH ,  LIENCRES BJORN

IPC: H04L29/08 ,  G06F13/12 ,  H04L29/06 ,  G06F13/38 ,  G06F13/42

Abstract: An outbound frame state machine (OFSM) which generates data frames for transmission over a data link. The outbound frame state machine (OFSM) is microcode controlled and includes an outbound frame header buffer (60) for containing information to be included in the header of the frame, a data buffer (26) for storing data characters to be included in the data frame, a data generator register (98) for providing special sequences of data characters, if required, and an outbound frame trace buffer for storing a trace log of all frames transmitted in the normal mode and to be used if the outbound frame state machine (OFSM) is operating in the simulated I/O mode or the diagnostic mode. In the normal mode of operation, the outbound frame state machine (OFSM) builds a data frame using header information from the frame header buffer, and may include data from the data buffer, all as specified by control bits stored in a control register. The control register may also include a bit for causing special sequences to be transmitted. In the simulation mode, frames are built by the outbound frame state machine (OFSM) and then wrapped back to the channel to be processed like frames from a control unit. In the diagnostic mode, the outbound frame state machine (OFSM) inserts various characters into the outbound data bit stream to create possible error situations on the data link.

公开(公告)号：DE69028462D1

公开(公告)日：1996-10-17

申请号：DE69028462

申请日：1990-06-23

Applicant: IBM

Inventor： CASPER DANIEL FRANCIS ,  FLANAGAN JOHN RICHARD ,  MIRACLE GERALD HOLT ,  NEUNER RICHARD ANDREW ,  POTVIN PETER LLOYD

IPC: G06F13/12

Abstract: A device control unit (19) operating under the protocol of a parallel bus (24) is connected by a serial link (18, 20) to a channel that is primarily adapted to operate under a different protocol with device control units connected by a serial link. An extender unit (22) interconnects the parallel bus (24) and the serial link (18, 20) and performs the specific operations of the parallel bus protocol. The channel and the extender unit (22) send serial frames on the link for data transfer and associated operations. These frames are constructed according to a protocol that provides an intermediate step in translating between the protocol of the serial control units and the protocol of the parallel control units. The channel is operable in either mode (by microcode) and the new protocol permits the serial channel mode to be independent of the protocol of the parallel control unit and it permits the two modes to be closely similar in many features. New operations using the protocol reduce the delays that would otherwise be required in the communications between the channel and the extender unit. The serial link (18, 20) can be made longer when the delays are reduced.