Cypress Semiconductor Corporation

Zilog, Inc.

Robert Walter Metzler, Jr

Melany Ann Richmond

David Gordon Wright

Warren S Snyder

Timothy John Williams

Harold Kutz

Bert Sullam

Craig Nemecek

Eric D Blom

Greg Verge

Jeffrey Erickson

A programmable system includes an input/output (I/O) pin that is configurable into multiple operational states. The programmable system further includes a memory device to store configuration data that, when provided to the I/O pin, causes the I/O pin to reconfigure into one of the operational states. When power is supplied to the system, the memory device is configured to provide the configuration data to the I/O pin prior to a system microcontroller becoming operational responsive to the power.

Configurable reset pin for input/output port

A microcontroller integrated circuit with a clock controller and a processor automatically switches the source of the clock signal that clocks the processor from a failed fast external precision oscillator to a slow internal backup oscillator, then enables a fast internal precision oscillator, and finally switches to the fast internal precision oscillator. A failure detection circuit within the clock controller detects a failure of the external precision oscillator and sends an associated interrupt signal to the processor. The clock controller decouples the external oscillator from the processor and couples the backup oscillator to the processor. The microcontroller integrated circuit then enables the fast internal precision oscillator, decouples the backup oscillator, and couples the fast internal precision oscillator to the processor. The microcontroller integrated circuit conserves power by powering up the fast internal precision oscillator only after the external clock source has failed and by then disabling the failure detection circuit.

Clock controller with clock source fail-safe logic

Growing community of inventors

Kirkland, WA, United States of America

Robert Walter Metzler, Jr