Browse Prior Art Database

Relative Address Encoding Scheme for Defective Bubble Minor Loops

IP.com Disclosure Number: IPCOM000050542D
Original Publication Date: 1982-Nov-01
Included in the Prior Art Database: 2005-Feb-10
Document File: 2 page(s) / 21K

Publishing Venue

IBM

Related People

Belser, KA: AUTHOR [+3]

Abstract

A technique is disclosed for encoding defective minor loop locations in a nine-chip bubble module. The data organization on the bubble chip is a major-minor loop structure. A record of data is read from or written to the module containing a number of 9-bit bytes equal to the number of minor loops in the major-minor loop array. Each bit in the 9-bit byte comes from a different chip, and each byte corresponds to a specific minor loop number on each chip. It is, therefore, sufficient to encode a bad byte position and a bad bit position within a byte for this record in order to identify a specific bad minor loop on a specific chip.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 61% of the total text.

Page 1 of 2

Relative Address Encoding Scheme for Defective Bubble Minor Loops

A technique is disclosed for encoding defective minor loop locations in a nine-chip bubble module. The data organization on the bubble chip is a major- minor loop structure. A record of data is read from or written to the module containing a number of 9-bit bytes equal to the number of minor loops in the major-minor loop array. Each bit in the 9-bit byte comes from a different chip, and each byte corresponds to a specific minor loop number on each chip. It is, therefore, sufficient to encode a bad byte position and a bad bit position within a byte for this record in order to identify a specific bad minor loop on a specific chip.

The technique reads data from an 8-bit auxiliary memory, called a map, to encode the bad minor loop information. In each 8-bit map word, 4 bits are used to encode the bad byte position within the record, and 4 bits are used to encode the bad bit position within the byte. The bad byte position is the same as a loop number. The bad bit position is the same as a chip number.

The bad bytes are encoded using a relative addressing method to control an address counter. This counter is initially 0 corresponding to the first byte of the record. The first four bits of the map word are used to increment this counter to the byte numbers where bad bits occur. The increments are 0 to 15. For increments greater than 15, several increments of 15 may be required that do not correspond to ba...