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:
Oct. 15, 1996
Filed:
Jul. 02, 1993
Rolf Hubert, Bonn, DE;
Klockner-Moeller GmbH, Bonn, DE;
Abstract
The invention discloses a memory access control for coupled mask-program over microcontrollers in particular in connection with applications for memory storage programmable control in the low-cost region. The coupling of the microcontroller (MC1) and of the memory access authorization to the external program memory storage and data memory storage (7) is thereby based on a hardware wiring circuit in cooperation with a handshake provided by software. Always only one microcontroller accesses the external program memory storage/data memory storage (7) while the other microcontrollers access their internal program memory storage. The memory storage access is coordinated by the microcontroller (MC1) operating as a master through its output port (Px.y). On the hardware side the memory storage access signal (PSEN) and the address access signal (ALE) are multiplexed for the access-authorized microcontroller. The coupling based on hardware uses thereby the bidirectionally operable input-output ports (P0-P3) and their alternative functions.