Patents by Inventor Koutarou Tagawa

Koutarou Tagawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20070069012
    Abstract: The present invention relates to a security protected circuit in a microcomputer, and more particularly provides a security protected circuit capable of controlling whether an ICE should be used without an external terminal and for protecting security. Specifically, collation data is supplied from an ICE to a JTAG I/F and the corresponding address data of built-in memory I obtained as reference data. Then, it is determined whether both data is matched by comparing both data in a comparison circuit, and a lock mechanism is released. Even when unmatched data is equal to or less than a prescribed value, the lock mechanism is released. Thus, a lock release device which protects security can be provided without providing a special terminal for lock release.
    Type: Application
    Filed: December 30, 2005
    Publication date: March 29, 2007
    Inventor: Koutarou Tagawa
  • Publication number: 20060075310
    Abstract: A microcomputer includes a bus, a CPU coupled to the bus, a trace data generating circuit coupled to the bus to output trace data of a process executed by the CPU at an output node, a memory coupled to the output node of the trace data generating circuit to store the trace data, a first register coupled to the bus to store a task number indicative of a task being executed by the CPU, and a control unit coupled to the first register to control on/off of outputting of the trace data from the trace data generating circuit in response to the task number.
    Type: Application
    Filed: December 29, 2004
    Publication date: April 6, 2006
    Applicant: Fujitsu Limited
    Inventor: Koutarou Tagawa
  • Patent number: 6944794
    Abstract: The invention is the microcontroller, which comprises CPU, a bus controller, an instruction address bus of a first bit number and an instruction code bus of a second bit number, which connect between the CPU and bus controller, and, further, a debug support unit, which is connected to the instruction address bus and instruction code bus. This debug support unit is also connected to an external in-circuit emulator via a tool bus of a third bit number that is smaller than the first bit number and via a bus-status signal line that reports on the status of this tool bus. The debug support unit has a data output circuit, which, in response to the status information signal, when the branch information contains a branch, outputs the converted instruction address serially to the tool bus, and when the branch information contains no branch, outputs a branchless signal to the tool bus.
    Type: Grant
    Filed: January 29, 2002
    Date of Patent: September 13, 2005
    Assignee: Fujitsu Limited
    Inventors: Toru Okabayashi, Koutarou Tagawa
  • Patent number: 6922794
    Abstract: In the microcomputer, the debug target circuit and the debugging circuit with an interface module to the in-circuit emulator are independently supplied with drive powers. Drive power is supplied to the debug target circuit and the debugging circuit, and various debug information is set by the in-circuit emulator. Thereafter, only supply of drive power to the debug target circuit is stopped. While the various debug information is held at the debugging circuit, supply of drive power to the debug target circuit is restarted. The debugging just after power throw-in is performed based on the debug information held in the debugging circuit.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: July 26, 2005
    Assignee: Fujitsu Limited
    Inventors: Koutarou Tagawa, Kouj Arai
  • Patent number: 6877113
    Abstract: A semiconductor integrated circuit including a debugging support unit and a buffer memory for temporarily storing trace data, the debugging support unit comprising a break detection member that detects a break signal externally inputted and a break determining member that determines whether the break signal requests to shift to break processing after outputting all the trace data stored in the buffer memory or the break signal requests to shift to the break processing with immediately suspending trace data outputting.
    Type: Grant
    Filed: March 21, 2002
    Date of Patent: April 5, 2005
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Saruwatari, Koutarou Tagawa
  • Publication number: 20040177238
    Abstract: A microprocessor which can shorten a testing period and facilitate the production of a test program is provided. The microprocessor of the present invention includes a CPU which performs certain arithmetic operations, an address bus connected to the CPU, a circuit unit, such as comparators, which utilizes an address on the address bus. In an function test of the circuit unit, a test circuit, instead of the CPU, generates a test address for testing the circuit unit through the address bus.
    Type: Application
    Filed: March 18, 2004
    Publication date: September 9, 2004
    Applicant: Fujitsu Limited
    Inventor: Koutarou Tagawa
  • Patent number: 6594782
    Abstract: A conflict detection unit monitors an input of branch information and an input of data access information. When an output data selection unit receives a notification from the conflict detection unit that there has arisen the conflict between the input of the branch information and the input of the data access information, the output data selection unit outputs branch information, and then data access information delayed by a delay unit, thereby outputting trace data.
    Type: Grant
    Filed: October 25, 1999
    Date of Patent: July 15, 2003
    Assignee: Fujitsu Limited
    Inventor: Koutarou Tagawa
  • Publication number: 20020199137
    Abstract: The invention is the microcontroller, which comprises CPU, a bus controller, an instruction address bus of a first bit number and an instruction code bus of a second bit number, which connect between the CPU and bus controller, and, further, a debug support unit, which is connected to the instruction address bus and instruction code bus. This debug support unit is also connected to an external in-circuit emulator via a tool bus of a third bit number that is smaller than the first bit number and via a bus-status signal line that reports on the status of this tool bus. The debug support unit has a data output circuit, which, in response to the status information signal, when the branch information contains a branch, outputs the converted instruction address serially to the tool bus, and when the branch information contains no branch, outputs a branchless signal to the tool bus.
    Type: Application
    Filed: January 29, 2002
    Publication date: December 26, 2002
    Applicant: Fujitsu Limited
    Inventors: Toru Okabayashi, Koutarou Tagawa
  • Publication number: 20020184561
    Abstract: In the microcomputer, the debug target circuit and the debugging circuit with an interface module to the in-circuit emulator are independently supplied with drive powers. Drive power is supplied to the debug target circuit and the debugging circuit, and various debug information is set by the in-circuit emulator. Thereafter, only supply of drive power to the debug target circuit is stopped. While the various debug information is held at the debugging circuit, supply of drive power to the debug target circuit is restarted. The debugging just after power throw-in is performed based on the debug information held in the debugging circuit.
    Type: Application
    Filed: September 24, 2001
    Publication date: December 5, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Koutarou Tagawa, Kouj Arai
  • Publication number: 20020146876
    Abstract: A semiconductor integrated circuit including a debugging support unit and a buffer memory for temporarily storing trace data, the debugging support unit comprising a break detection member that detects a break signal externally inputted and a break determining member that determines whether the break signal requests to shift to break processing after outputting all the trace data stored in the buffer memory or the break signal requests to shift to the break processing with immediately suspending trace data outputting.
    Type: Application
    Filed: March 21, 2002
    Publication date: October 10, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Toshiaki Saruwatari, Koutarou Tagawa
  • Patent number: 5530818
    Abstract: A semiconductor integrated circuit device has a first unit for generating an address and supplying the address to an external device, a plurality of registers for storing predetermined data which designate an address space, a plurality of comparators, and a second unit. Each of the comparators is used to compare the address output from the first unit and the predetermined data stored in each of the registers. The second unit is used to merge a plurality of outputs of the comparators and to generate an enable signal to activate the external device, when at least one of the outputs of the comparators indicates coincidence between the address and the predetermined data. The semiconductor integrated circuit device makes it possible to activate the external device when at least one of the outputs of the comparators indicates coincidence between the address and the predetermined data.
    Type: Grant
    Filed: July 8, 1993
    Date of Patent: June 25, 1996
    Assignee: Fujitsu Limited
    Inventor: Koutarou Tagawa