公开(公告)号：GB2377144A

公开(公告)日：2002-12-31

申请号：GB0117092

申请日：2001-07-13

Applicant: IBM

Inventor： BEER REGINALD ,  CASHMAN PAUL NICHOLAS ,  JUDD IAN DAVID ,  HOOTON PAUL ,  MADDOCK ROBERT FRANK ,  MORRIS NEIL ,  NICHOLSON ROBERT BRUCE ,  WHYTE BARRY DOUGLAS

IPC: H04L12/437 ,  H04L45/28

Abstract: A method and apparatus for recovery from faults in a loop network (400) is provided. The loop network (400) has a host means (402), a first loop and a second loop (406, 408), a plurality of ports (410) connected to each of the loops (406, 408) and a control device (414, 440) on or connected to each loop (406, 408) with bypass control over at least one of the ports (410) connected to the loop (406, 408). In the event of a failure on the first loop (406), the host means (402) instructs the bypassing of at least one port (410) on the first loop (406), the host means (402) sending the instructions via the control device (414, 440) on or connected to the second loop (408). The host means (402) may determine the physical topology of the ports (410) on the first and second loops (406, 408) such that when a failure is reported to the host means (402) by a port (432) on the first loop (406), the host means (402) instructs the bypassing of a port (434) in a specific relationship to the reporting port (432) on the first loop (434). The host means (402) may instruct the bypassing of all ports (416) on the first loop (406) and subsequently selectively un-bypass ports (416) to ascertain the location of a faulty port or ports.

公开(公告)号：SG44451A1

公开(公告)日：1997-12-19

申请号：SG1996000502

申请日：1991-02-19

Applicant: IBM

Inventor： JUDD IAN DAVID ,  BUCKLAND PATRICK ALLEN ,  CATH ROGER GOODWIN ,  COCKBURN GORDON JOHN ,  SHORT WILLIAM ANTHONY

IPC: G06F3/06 ,  G06F13/28

公开(公告)号：CA2078914C

公开(公告)日：1997-03-25

申请号：CA2078914

申请日：1992-09-23

Applicant: IBM

Inventor： JUDD IAN DAVID ,  APPERLEY NORMAN

IPC: G06F3/06 ,  G11B19/28 ,  G11B27/00 ,  G11B27/10 ,  G06F13/10

Abstract: A spindle synchronization technique is described which is useful in a disk array subsystem comprising a plurality of disk drives (40,41,42,43) connected by means of serial links (25,26,27,28) to a disk drive controller (20). Data and command information is transmitted over the link in the form of multi-character frames, the flow of which is regulated by special ten bit protocol characters. A SYNC protocol character is defined which is used to synchronize the spindles of the disk drives. This SYNC character is issued by controller to selected ones of the drives over the same link used for the transmission of the command and data information. The SYNC character may be interleaved between the characters of frames being transmitted over the link.

公开(公告)号：GB2268373A

公开(公告)日：1994-01-05

申请号：GB9213151

申请日：1992-06-20

Applicant: IBM

Inventor： JUDD IAN DAVID ,  BEER REGINALD

IPC: H04L1/00 ,  H04L1/18 ,  H04L12/28 ,  H04L69/40 ,  H04L1/16

Abstract: An error recovery method for use in an information communication system which comprises a plurality of nodes connected by links. Information is transferred between the nodes in frames of predefined types, including at least a first frame type used to transfer data and a second frame type used for error recovery. Each node has at least a first and a second mode of operation, in the first mode frames of both first and second types are accepted, in the second mode frames of the first type are discarded and only frames of the second type are accepted. A master node which controls error recovery is selected from amongst those nodes which can initiate transfers.

公开(公告)号：DE3068551D1

公开(公告)日：1984-08-16

申请号：DE3068551

申请日：1980-10-31

Applicant: IBM

Inventor： JUDD IAN DAVID

IPC: G09G1/00 ,  G09G1/04 ,  G09G1/16 ,  H04N3/233 ,  H04N3/22

Abstract: Cathode ray tube drive circuitry in which non-linearity of the line scan is corrected by varying the frequency of the pel clock oscillator in accordance with anticipated variations in scanning speed. Predetermined speed corrections are stored in a digital store 23 and, by means of digital to analog converter 24 and integrator 25, are applied to the control input of a voltage controlled oscillator 13. Synchronization of the pel clock with the X-deflection waveform is effected by means of a parallel phase-locked loop comprising counter 15, sample and hold 18, amplifier 20 and low pass filter 21. Preferably a sinusoidal waveform is applied to the X-deflection coil in such a manner as to have a bidirectional raster scan, the X-deflection coil forming part of a tuned circuit of the sinusoidal waveform generator.

公开(公告)号：AU5348979A

公开(公告)日：1980-06-19

申请号：AU5348979

申请日：1979-12-05

Applicant: IBM

Inventor： JUDD IAN DAVID

IPC: H04N1/387 ,  G06T3/40 ,  H04N1/393 ,  G06F7/28 ,  H04N1/40

公开(公告)号：DE2752421A1

公开(公告)日：1978-06-22

申请号：DE2752421

申请日：1977-11-24

Applicant: IBM

Inventor： EVANS JOHN MAURICE ,  JUDD IAN DAVID ,  LOVIE RICHARD HENRY ,  MINSHULL JOHN FRANCIS

IPC: H04N5/262 ,  G06K9/54 ,  G06T3/00 ,  G06T9/20 ,  G06T11/20 ,  G09G5/36 ,  H04N1/411 ,  G06K9/16 ,  G06K15/20

Abstract: Graphical data on a document is raster scanned and the resulting bit pattern is processed to provide a processed bit pattern which represents lines which each are a single pel in width and indicative of the shapes of objects scanned on the document. These single pel wide lines may represent the outlines of objects on the center lines. The processed bit pattern is then directed to a line follower in which bits representing contiguous pels are detected and tested for linearity. When contiguous pels fail the linearity test, a new vector is started and the vector being tracked is terminated. Hardware for performing these operations is described. The resulting vector list is stored until needed for display. Optionally a display station can be used to correct faulty vectors or to encode alphanumeric data in a more convenient format than vector coding.