US Patent No: 5,819,087

Number of patents in Portfolio can not be more than 2000

Flash ROM sharing between processor and microcontroller during booting and handling warm-booting events

Stats

ATTORNEY / AGENT: (SPONSORED)
 

Importance

Loading Importance Indicators... loading....

Abstract

A computer system having a processor, a microcontroller, a flash ROM is provided with an address remapper for handling warm-boot events, and an arbiter for selectively assigning the ownership of the flash ROM to either the microprocessor or the microcontroller. The arbiter assigns the flash ROM initially to the microcontroller when power is initially provided to the system. After the flash ROM boots up and checks the integrity of the flash ROM and updates the content of the flash ROM with valid firmware if necessary, the microcontroller releases the flash ROM to the microprocessor to enable the computer system to proceed with the normal boot-up process. In this process, various system self tests are performed. Next, the microprocessor copies or shadows one or more portions of the flash ROM BIOS into a main memory array. After the shadow operation, the processor sets a remap bit to indicate that the ROM BIOS content has been copied into the main memory array. The setting of the remap bit enables the remapper to deflect accesses to the flash ROM. The restarting of the clock signal to the microcontroller to switch the ownership of the flash ROM back to the microcontroller. In the event that the microprocessor needs to regain access to the flash ROM contents, the microprocessor writes to the mailbox register of the arbiter to request access to the flash ROM. The microprocessor waits for a confirmation from the arbiter that the microcontroller is entering an idled mode. Next, the microprocessor halts the clock of the microcontroller. These events cause the microcontroller to float or tristate the signal lines going from the microcontroller to the flash ROM such that the microprocessor can drive the signal lines without any conflict potentials. In this manner, the microprocessor can still access the shared flash ROM after it has booted up. Thus, the system cost is reduced, the system reliability is enhanced, while the system accessibility to the flash ROM after the boot-up period is still preserved.

Loading the Abstract Image... loading....

First Claim

Related Publications

Loading Related Publications... loading....

Patent Owner(s)

Patent OwnerAddressTotal Patents
HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.HOUSTON, TX25733

International Classification(s)

  • [Classification Symbol]
  • [Patents Count]

Inventor(s)

Inventor Name Address # of filed Patents Total Citations
DeLisle, David J Spring, TX 26 547
Le, Hung Q Austin, TX 61 613
Melo, Maria Lucia Houston, TX 2 58

Cited Art

Patent Info (Count) # Cites Year
 
CIRRUS LOGIC, INC. (1)
5,701,477 Method and apparatus for master boot record shadowing 50 1995
 
INTEL CORPORATION (1)
5,410,707 Bootstrap loading from external memory including disabling a reset from a keyboard controller while an operating system load signal is active 57 1994
 
KABUSHIKI KAISHA TOSHIBA (1)
5,269,022 Method and apparatus for booting a computer system by restoring the main memory from a backup memory 209 1991
 
LENOVO (SINGAPORE) PTE LTD. (1)
5,022,077 Apparatus and method for preventing unauthorized access to BIOS in a personal computer system 184 1989
 
NXP B.V. (1)
5,603,055 Single shared ROM for storing keyboard microcontroller code portion and CPU code portion and disabling access to a portion while accessing to the other 14 1994
 
SEAGATE TECHNOLOGY LLC (1)
5,327,549 Data storage system including a BIOS extension memory on an adapter between a host computer and disk drive 19 1993

Patent Citation Ranking

Forward Cites

Patent Info (Count) # Cites Year
 
HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P. (10)
6,128,732 Implementing universal serial bus support with a minimum of system RAM 20 1997
6,154,838 Flash ROM sharing between processor and microcontroller during booting and handling warm-booting events 27 1998
6,115,815 Boot drive selection and hibernation file detection 16 1998
6,601,165 Apparatus and method for implementing fault resilient booting in a multi-processor system by using a flush command to control resetting of the processors and isolating failed processors 13 1999
6,816,934 Computer system with registered peripheral component interconnect device for processing extended commands and attributes according to a registered peripheral component interconnect protocol 7 2003
7,099,986 High speed peripheral interconnect apparatus, method and system 7 2004
7,587,542 Device adapted to send information in accordance with a communication protocol 6 2005
7,464,207 Device operating according to a communication protocol 9 2005
8,392,901 Replacing a ROM image in a computer's ROM 0 2005
7,908,470 Multi-processor computer with plural boot memories 0 2006
 
O2MICRO INTERNATIONAL LIMITED (4)
7,088,076 Power management for battery powered appliances 16 2003
7,791,314 Power management topologies to control power between a DC power source and one or more batteries to a system load 0 2008
8,350,534 Method and electronic circuit for efficient battery wake up charging 0 2009
8,120,312 Power management topologies to control power between a DC power source and one or more batteries to a system load 0 2010
 
AMAZON TECHNOLOGIES, INC. (2)
8,381,264 Managing hardware reboot and reset in shared environments 0 2009
8,335,237 Streamlined guest networking in a virtualized environment 0 2011
 
BROADCOM CORPORATION (2)
6,971,033 Method and apparatus for improving bus master performance 5 2003
7,523,324 Method and apparatus for improving bus master performance 1 2007
 
BROTHER KOGYO KABUSHIKI KAISHA (1)
6,173,412 Apparatus and method for initializing a writeable/nonvolatile memory device 2 1998
 
DELL PRODUCTS L.P. (1)
6,832,304 System, method and computer program product for mapping system memory in a multiple node information handling system 1 2002
 
DELL USA, L.P. (1)
6,298,427 Method and apparatus for mapping hard disk partitions and block devices to logical drives in a computer system 12 1999
 
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. (1)
6,532,587 Electronic equipment 3 1999
 
NATIONAL SEMICONDUCTOR CORPORATION (1)
7,318,173 Embedded controller based BIOS boot ROM select 11 2003
 
NXP B.V. (1)
6,629,241 Data processing apparatus with non-volatile memory for both program and data 0 2000
 
RENESAS ELECTRONICS CORPORATION (1)
6,745,278 Computer capable of rewriting an area of a non-volatile memory with a boot program during self mode operation of the computer 5 2001
 
SPANSION LLC (1)
5,999,476 Bios memory and multimedia data storage combination 14 1997
 
SPRINT COMMUNICATIONS COMPANY L.P. (1)
7,409,435 Integrated services hub binary file trial run process 1 2002
 
STANDARD MICROSYSTEMS CORPORATION (1)
7,930,576 Sharing non-sharable devices between an embedded controller and a processor in a computer system 0 2007
 
SUN MICROSYSTEMS, INC. (1)
5,935,242 Method and apparatus for initializing a device 124 1996
 
WINBOND ELECTRONICS CORP. (1)
8,285,895 Handshake free sharing in a computer architecture 0 2007
 
OTHER [CHECK PATENT PROFILE FOR ASSIGNMENT INFORMATION] (1)
7,360,130 Memory with integrated programmable controller 2 2005