The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 08, 1980
Filed:
Oct. 21, 1977
David J Roberts, Eastleigh, GB;
John Simmons, Chandlers Ford, GB;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A data processing system is described which issues value documents e.g. tickets or information under the control of output instructions and is designed to prevent a person attempting fraud using an unauthorized program obtaining the value documents or information. The system includes a data processor controlling output units which can issue value documents or information and data storage. The data storage is divided into a secure store containing the output instructions arranged to make tampering difficult and a free storage into which an operator may load a program. Security logic is provided to check that an output instruction has originated in the secure store and to prevent operation of an output unit which receives output instructions from free storage. This makes it difficult for a person attempting fraud to produce value documents or information by loading a program into free storage. The secure storage is preferably a read only store programmed during manufacture. When secure and free storage share a common memory bus, the security logic monitors addresses used to fetch instructions.