Sgs-thomson Microelectronics S.a.

Stmicroelectronics S.a.

Philippe Basset

Franck Roche

Pierre Tarayre

A microprocessor includes a processing unit, an address bus connected to an addressable memory space, and executes instructions from an instruction set for accessing the addressable memory space. The addressable memory space is for a lower memory area and an extended memory area. The instruction set includes a first instruction group for accessing the lower memory area, and a second instruction group that is distinct from the first instruction group for accessing the extended memory area.

Microprocessor having an extended addressable space

An integrated circuit comprises a microprocessor (1), a memory (2) and one or more internal peripherals (3) connected, firstly, to one another and, secondly, to circuits external (4) to this integrated circuit by means of connections circuits (5). The peripherals comprise circuits called options circuits (6) enabling the operation of these peripherals to be configured. For an operating session corresponding to putting of the integrated circuit into service, the operations of these peripherals are defined as a function of information elements stored in the the first part of the memory (7). The memory also has a second part (8) designed to store instructions that can be executed by the microcontroller. This configuration of the peripherals takes place when the integrated circuit is put into service, by the linking of said peripherals to said first part of the memory. This memory is of the programmable type. The circuits known as options circuits possess means for being configured by default for a particular mode of operation of the microprocessor of the integrated circuit called the programming mode. In this mode, this microprocessor is capable of writing in the first part of the memory.

Integrated circuit comprising a microprocessor, a memory and internal

Disclosed is a microcomputer capable of working in emulation mode with internal and external peripherals. The microcomputer comprises a central processing unit, an internal address decoder, an internal memory and internal peripherals connected to a data and address bus. The central processing unit has input/output ports for external access in user mode according to the invention. The input/output ports are connected to the external peripherals and to an external address decoder. The external address decoder sends out a signal applied to the central processing unit to block the pre-loading of the internal address decoder when an external peripheral is selected in emulation mode.

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Meylan, France

Philippe Basset