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:
Nov. 26, 2002
Filed:
May. 14, 1999
Conrad A. Theron, San Jose, CA (US);
Donald H. St. Pierre, Jr., Nashua, NH (US);
Xilinx, Inc., San Jose, CA (US);
Abstract
A method is disclosed for communicating with an FPGA interface device having a microcontroller when the on-board microcontroller is not responsive to commands from a host system. If the host system determines that the microcontroller is not responsive to commands, the host system sends a null character to the interface device at a predetermined baud rate which is significantly distinguishable from baud rates normally used for communicating with the microcontroller. A logic circuit on the interface device monitors the baud rate of incoming data, and if a null character at the predetermined baud rate is detected, the logic circuit toggles the reset pin of the microcontroller. In response thereto, the microcontroller re-boots itself, and is thereafter able to communicate with the host system. Additional commands are provided to the interface device by using other baud rates which are significantly distinguishable from the baud rates normally used.