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:
Apr. 25, 1995
Filed:
Dec. 17, 1992
Kin C Yu, Burlington, MA (US);
Bull HN Information System Inc., Billerica, MA (US);
Abstract
A hybrid system environment includes a proprietary operating system and processing unit and a non-proprietary operating system (UNIX based) and processing unit tightly coupled to a system bus in common with a main memory and a plurality of controllers which include a number of multiline communications controllers and communicates through a common area of main memory. Terminal connections to the communications controllers for virtual terminal processing are made through a UNIX virtual terminal driver and system proprietary communications software components which include a server, network terminal driver (NTD) and multiplexer driver modules. The UNIX based operating system further includes a multiplexer terminal driver and a switching mechanism which is included within the virtual terminal driver. The mechanism enables switching from virtual terminal processing to direct terminal processing wherein communications is established between the multiplexer terminal driver and the communications controllers. An interrupt dispatching mechanism enables interrupts from the controllers to be rerouted to the multiplexer terminal driver and properly dispatched to the driver interrupt handler routines on the basis of line number thereby reducing processing delays.