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:
Mar. 24, 1998
Filed:
Mar. 13, 1997
David Frank Harrison, Boulder Creek, CA (US);
Russell T Williams, San Jose, CA (US);
Thomas Eugene Saulpaugh, San Jose, CA (US);
Apple Computer, Inc., Cupertino, CA (US);
Abstract
A computer has a device driver and an operating system that call a consolidated buffer service routine to coordinate the transfer of data between a main memory and an external device. The consolidated buffer service routine includes a memory preparation service routine and a memory checking service routine. The memory preparation service routine coordinates data transfers between the external device and the memory with the operating system and a data cache, and with other data transfers. The memory preparation service routine ensures that the buffer remains assigned to the memory ranges until the memory checking service routine relinquishes the buffer. Before calling the memory preparation service routine, and I/O preparation table is set which defines the addresses and the type of addresses of the buffer, the size of the data to be transferred, the page size of the buffer, and flags defining data flow and type.