Patent ID: 8880826
Filing Date: 2014-11-04
Classification: G06F

Abstract:
1. A Write-Once Read-Many (WORM) memory controller operably coupleable to a memory storage device and to a host processing system, and operable to: initialize WORM functionality in the memory storage device; receive first data from the host processing system, the first data being addressed to a sector in the memory storage device; in response to receiving the first data, issue a first verification command to the memory storage device, wherein the first verification command includes a first tag value which indicates that a specified sector has not been written to since being initialized; receive a first verification reply from the memory storage device, wherein the first verification reply includes an indication that the first tag value matches a tag field of the sector; store the first data in the sector and a second tag value different from the first tag value in the tag field of the sector in response to receiving the first verification reply; receive second data from the host processing system, the second data being addressed to the sector; in response to receiving the second data, issue a second verification command to the memory storage device, wherein the second verification command includes the first tag value; receive a second verification reply from the memory storage device, wherein the second verification reply includes an indication that the tag field of the sector includes the second tag value; and prevent the second data from being stored in the sector based upon the presence of the second tag value in the tag field.