(19)

(11)

EP 0 217 905 A1

(12)

(43) Date of publication: 15.04.1987 Bulletin 1987/16 (21) Application number: 86902451.0 (22) Date of filing: 15.04.1986

(51) International Patent Classification (IPC):  G11C 29/ 00( . ) G06F 11/ 20( . ) (86) International application number: PCT/GB1986/000211 (87) International publication number: WO 1986/006186 (23.10.1986 Gazette 1986/23)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 15.04.1985 GB 19850009632 (71) Applicant: SINCLAIR RESEARCH LIMITED Milton, Cambridge CB4 4AE (GB)	(72) Inventor: CATT, Ivor St. Albans AL3 4HQ (GB)