| 摘要 |
<p>A magnetic bubble domain memory device that includes a magnetic domain data chip having a major-minor (20, 26) loop organization with on-chip firmware providing redundancy information enabling the use of the chip even though one or more defective minor loops may be present thereon. One of the pages (68) is written in the minor loop (26), where a page is defined as a common bit position in each of the plurality of minor loops, with a series of magnetic domains having an odd total number. The next succeeding page (70) in the minor loops contains a series of magnetic domains and voids which are representative of the loop numbers of defective minor loops on the chip with the remaining pages (72) in the minor loop having an even number of magnetic domains contained in each of the pages. Collectively, the pages containing the odd and even number of magnetic domains together with the page containing the map of the defective minor loops comprise the on-chip firmware providing redundancy information. This magnetic domain structure is capable of screening out defective minor loops in the read and write operation, and enables synchronization of the magnetic domain device such that a selected page of data may be readily accessed from a plurality of minor loops when desired. </p> |
