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:
Jun. 25, 1996
Filed:
Jun. 16, 1994
Applicant:
Inventors:
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04J / ;
U.S. Cl.
CPC ...
34082507 ; 34082552 ; 370 79 ; 370 82 ;
Abstract
A method of communications between a master unit and a slave unit of a supervisory control and data acquisition system is provided. The communications protocol has at least two bytes of data where the first byte (100) is an address byte containing address information for addressing the slave unit and the second byte (101) is a control byte containing an expansion bit and two address/type variable bits to be interpreted by the slave according to a rule set. In the rule set, the meaning of certain control bits (107) is related to the state of an expansion bit (103). The expanion bit defines the presence or absence of a third byte (102).