Renesas Electronics Corporation

Renesas Technology Corp.

Hisayoshi Ide

Naohiko Irie

Saneaki Tamaki

Motokazu Ozawa

Miki Hayakawa

Information processing system including a first and a second operation mode with operating current lower than the first, a register holding an address of an instruction executed by a processing unit first when a boot address register returns from second to first operation mode, wherein the address is output to the processing unit when second to first operation mode shifting, wherein the boot address register is rewritable, an information holding circuit holding a value of a peripheral circuit module register, wherein the information holding circuit holds, in the second operation mode, information about the peripheral circuit module register, and, transfers information held in the information holding circuit to the peripheral circuit module register regarding a second-to-first operation mode shift, and wherein when an interrupt request is posted from outside the system in the second operation mode, the information processing system performs interrupt processing corresponding to the interrupt request.

Information processing device

An information processing device, including: a processing unit; a peripheral circuit module; and a boot address register, wherein the information processing device comprises a first operation mode and a second operation mode having an operating current which is lower than that of said first operation mode, wherein the boot address register holds an address of an instruction to be executed by said processing unit first when the boot address register returns from said second operation mode to said first operation mode, wherein the address is output from said boot address to the processing unit when said information processing device shifts from said second operation mode to said first operation mode.

A mechanism of making a low standby current caused by power off compatible with a fast return operation from a standby caused by an interrupt is realized. An information processing device has a first area that includes a central processing unit and peripheral circuit modules, a second area having information holding circuits for holding values of registers contained in the peripheral circuit modules, and a first power switch for controlling supply of a current to the first area. When the information processing device operates in a first mode, an operating current is supplied to the first area and the second area. When the information processing device operates in a second mode, the first power switch is controlled so that the supply of the current to the first area can be shut off, and the supply of the current to the second area is continued.

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Kunitachi, Japan

Hisayoshi Ide