(19)

(11)

EP 0 591 319 A1

(12)

(43) Date of publication: 13.04.1994 Bulletin 1994/15 (21) Application number: 92913070.0 (22) Date of filing: 19.06.1992

(51) International Patent Classification (IPC):  G06F 17/ 24( . ) (86) International application number: PCT/GB1992/001121 (87) International publication number: WO 1993/000642 (07.01.1993 Gazette 1993/02)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI LU MC NL SE (30) Priority: 21.06.1991 GB 19910013390 (71) Applicant: AMBIT RESEARCH LIMITED London SW6 4LX (GB)	(72) Inventor: CAWLEY, William Frederick Leominster, Herefordshire HR6 0AX (GB) (74) Representative: Shaw, Laurence  5th Floor, Metropolitan House, 1 Hagley Road, Edgbaston Birmingham B16 8TG Birmingham B16 8TG (GB)