Patent · US Expired

Method and apparatus for diagnosis and behavior modification of an embedded microcontroller

US7076708B2 · kind B2 · utility

18Cited by
17References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 25, 2003
Grant dateJul 11, 2006
Priority date
Expiry dateDec 28, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/318544
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method of accessing an embedded microcontroller, by programmably selecting pins of the microcontroller for use as test lines, receiving a scan command at an input test line pin, emulating a virtual scan path through a logical block of the microcontroller, and transmitting scan results to an output test line pin. The microcontroller can provide such emulation of scan testing in compliance with the JTAG standard for a test access port and boundary-scan architecture. The test line pins are interconnected with a test bus structure to form a scan ring with other components of a data processing system, such as a microprocessor. The emulation can be used to change a functional mode of the microcontroller, or gather diagnostic information after a system error. The microcontroller assigns a high-priority internal interrupt routine to service test line pin activity. The virtual scan path need not include all internal microcontroller resources, and the scan path can be programmably varied by the application designer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.