(12) United States Patent ao) Patent No.: Us 7,050,184 Bi
Miyamoto (45) Date of Patent: May 23,2006
(54) DATA TRANSFER APPARATUS AND
METHOD, AND DATA TRANSFER SYSTEM
(75) Inventor: Ryosuke Miyamoto, Urayasu (JP)
(73) Assignee: Canon Kabushiki Kaisha, Tokyo (JP)
( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.
(21) Appl. No.: 09/299,875
(56) References Cited
U.S. PATENT DOCUMENTS
5,650,862 A 7/1997 Shimizu et al 358/448
6,249,835 Bl * 6/2001 Isoda 710/201
* cited by examiner
Primary Examiner—Mark Wallerson
(74) Attorney, Agent, or Firm—Fitzpatrick, Cella, Harper &
(22) Filed: Apr. 27, 1999
(30) Foreign Application Priority Data
Apr. 30, 1998 (JP) 10-121063
(51) Int. CI.
(52) U.S. CI 358/1.15; 358/1.13; 358/468
(58) Field of Classification Search 358/1.1,
358/1.12, 1.13, 1.14, 1.15, 405, 407, 468,
See application file for complete search history.
In a conventional system to which a plurality of devices are connected by a serial bus, the throughput of the network decreases due to transfer of a large amount of data. In this invention, a controller connected to the devices via a 1394 serial bus calculates a band width necessary for data transfer in a specific one of the devices, ensures the first channel corresponding to the band width, and transfers data to the specific device using the first channel. This enables preferential data transfer to the specific device to avoid a decrease in throughput.
45 Claims, 30 Drawing Sheets