(19)

(11)

EP 0 163 721 A1

(12)

(43) Date of publication: 11.12.1985 Bulletin 1985/50 (21) Application number: 85900277.0 (22) Date of filing: 14.11.1984

(51) International Patent Classification (IPC):  G11C 11/ 34( . ) G11C 7/ 06( . ) (86) International application number: PCT/US1984/001839 (87) International publication number: WO 1985/002314 (06.06.1985 Gazette 1985/13)

(84) Designated Contracting States: BE DE FR NL SE (30) Priority: 02.12.1983 US 19830557663 (71) Applicant: AT&T Corp. New York, NY 10013-2412 (US)	(72) Inventors: O'CONNOR, Kevin, John Center Valley, PA 18034 (US) PROCYK, Frank, John Center Valley, PA 18034 (US) (74) Representative: Buckley, Christopher Simon Thirsk, et al  AT&T (UK) Ltd. 5 Mornington Road Woodford Green Essex IG8 0TU Woodford Green Essex IG8 0TU (GB)