The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 08, 2011
Filed:
Aug. 06, 2007
Atsuya Takahashi, Mishima, JP;
Atsuya Takahashi, Mishima, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
Provided is an image forming system that suppresses an increase in number of signal lines between an image forming apparatus and optional units, curtails communication time period and alleviates communication load. To accomplish this, an image forming system includes an image forming apparatus and one or more optional units removably attached to the image forming apparatus. The image forming apparatus transmits a specifying command and an instruction command to all of the optional units by outputting the commands on a single common signal line. Each optional unit outputs acknowledgement status on a single common signal line in a case where an identifier appended to the instruction command is the same as an acquired identifier. If the identifiers are different, on the other hand, each optional unit outputs a value indicating whether it itself is currently performing an operation in response to acknowledgement status transmitted by another optional unit.