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:
Jan. 02, 1979
Filed:
Jan. 19, 1977
Robert E Huettner, Acton, MA (US);
John P Grandmaison, Hampton, NH (US);
John H Vernon, Milford, MA (US);
Richard A Lemay, Bolton, MA (US);
Edward Beauchemin, Marlboro, MA (US);
Honeywell Information Systems Inc., Waltham, MA (US);
Abstract
Data is transferred between a main memory in a data processing system and communication channels under the control of communications control blocks provided in an auxiliary memory, each of which control blocks includes a starting address, range and status information so as to enable the transfer of data to data blocks included in the main memory as indicated by the starting address in the control blocks. A predetermined number of control blocks is allocated in the auxiliary memory for each communications channel and the transfer of all such data is performed utilizing as many of the predetermined number of control blocks as required for the channel until the transfer is complete as indicated by the last such control block utilized in the transfer. Control blocks are loaded in the auxiliary memory under control of the central processor of the system and are periodically accessed by the processor to determine the status of data transfer operations. Circuits are provided for preventing the loading in the auxiliary memory of more than the predetermined number of control blocks for a channel and for preventing the execution of a status inquiry for a channel when no control blocks for that channel are in the active state.