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. 07, 1977
Filed:
Dec. 22, 1975
Franklin Charles Breslau, Teaneck, NJ (US);
Gerald Goertzel, White Plains, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A CPU communicates via an indirect memory access channel (IMA) to many devices on a high speed loop and an asynchronous low speed loop. The IMA connects to a loop adaptor (LAD) which connects to the primary parallel loop. A low speed serial loop is coupled to the primary loop through a general device adaptor and another LAD. The time of the loops is broken down into frames divided into inbound and outbound halves. Each half frame carries address and control data. The address in each frame is highly variable depending upon demand by devices and the allocation of service is controlled by interrupt signals by devices on the loops which can demand service whenever an empty or free inbound frame passes by their inputs as indicated by signals known as free bit signals, which are suppressed as soon as a device seizes a free inbound frame.