US20020023185A1 - Memory card utilizing two wire bus - Google Patents

Memory card utilizing two wire bus Download PDF

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US20020023185A1
US20020023185A1 US09/833,871 US83387101A US2002023185A1 US 20020023185 A1 US20020023185 A1 US 20020023185A1 US 83387101 A US83387101 A US 83387101A US 2002023185 A1 US2002023185 A1 US 2002023185A1
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bus
controller
memory
card
serial
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US6385685B1 (en
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Timothy Dell
Bruce Hazelzet
Mark Kellogg
Clarence Ogilvie
Paul Stabler
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International Business Machines Corp
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International Business Machines Corp
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    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11CSTATIC STORES
    • G11C5/00Details of stores covered by group G11C11/00
    • G11C5/06Arrangements for interconnecting storage elements electrically, e.g. by wiring
    • G11C5/066Means for reducing external access-lines for a semiconductor memory clip, e.g. by multiplexing at least address and data signals

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  • This invention relates generally to busses for memory cards to allow a Digital Signal Processor (DSP) on a memory DIMM or SIMM to communicate with a system memory controller, and more particularly to the use of a serial bus for communication of a DSP on a memory card with a system memory controller.
  • DSP Digital Signal Processor
  • a serial bus and connection to a device on a computer system preferably through a controller such as a system memory controller is provided on a memory card having a DSP and a memory bus controller to allow the DSP on the memory card to gain access to the device on the system bus without the need to use the system memory bus.
  • the serial bus in its preferred form is a two wire serial bus which connects the device to the DSP through a memory bus controller and preferably through the system memory controller. If more than one memory card is present with DSPs or more than one device contending for access, the system memory controller or other controller will arbitrate the access of each memory card or contending device.
  • serial bus will signal the system memory controller when it wants access to the particular device, and the system memory controller will act as arbitrator to grant or not grant access to the particular memory card or device requesting access. If access is granted the bus memory controller outputs the required control or command word on the serial bus followed by the address and the required data.
  • This serial information is received by the system memory controller or some other controller which packets it, and, when the transmission is complete, outputs the information rapidly on a parallel bus, e.g. a PCI bus to the device which needs the information.
  • a parallel bus e.g. a PCI bus to the device which needs the information.
  • each DSP in effect becomes a bus master when so required for transferring data to and from a device other than the specific memory card on which it resides.
  • the DSP can also take control for reading data from a device using the serial bus.
  • FIG. 1 is diagram of a DIMM incorporating a DSP and memory bus controller and having a two wire serial bus communicating with a system memory controller;
  • FIG. 2 is a block diagram or the connection of several memory modules to a system memory controller.
  • a memory module 8 such as a DIMM or SIMM is provided which includes a printed circuit card 10 having a plurality of synchronous DRAMs (SDRAMs) 12 a through 12 h.
  • SDRAMs synchronous DRAMs
  • the synchronous DRAMs 12 a - 12 h which are conventional SDRAMS, are configured and arranged to store both data bits and check bits written to them by the computer system.
  • the SDRAM's 12 a - 12 h each have memory location 13 a - 13 h reserved for a signal processing element which will be described presently.
  • the circuit card 10 has a memory bus which includes a memory data bus 14 and a memory address/control bus 16 ; a system clock line 18 , a wait line 20 and an interrupt request line 22 are also present.
  • Memory data bus 14 , memory address/control bus 16 , system clock 18 , wait line 20 and interrupt request line 22 are all connected to I/O connectors sometimes referred to as pins 26 .
  • the I/O connectors 26 provide an interface to a system memory controller 28 , which is a part of the CPU or computer 6 .
  • the system memory controller 28 also controls a PCI bus 30 (and optionally other buses not shown).
  • the PCI bus 30 has thereon devices such as a codec 32 .
  • the memory card 10 also has a memory bus controller 34 which is connected to the memory data bus 14 , the memory address/control bus 16 , the system clock 18 , the wait line 20 , and the interrupt request line 22 .
  • the bus controller 34 is connected to a signal processing element 36 which in the preferred embodiment is a digital signal processor (DSP).
  • DSP digital signal processor
  • a particularly useful DSP is any one of the TMS 320C54X family manufactured by Texas Instruments, Inc. This particular DSP family includes an external cache memory 38 .
  • the bus controller 34 and DSP 36 are interconnected by a chip address bus 40 , a chip data bus 42 and control lines 44 that pass various control signals between the bus controller 34 and the DSP 36 . This type of connection is well known in the art.
  • the memory data bus 14 has FET switches 50 therein. (It is to be understood that the memory data bus 14 is comprised of multiple lines, one for each bit and there is an FET 50 for each bit line.)
  • the memory data bus 14 may be an 8 bit bus, a 16 bit bus, a 32 bit bus, or a 64 bit bus, and indeed any size data bus which includes whatever number of data lines are required.
  • the system clock line 18 is also connected to the DSP 36 in the preferred embodiment; however, it is to be understood that a separate clock could be provided for the DSP if different timing is used on the card from the timing used in the CPU. However, the preferred embodiment for most instances is to use the system clock for clocking the functions and signals on the memory module.
  • a two wire serial bus comprised of wires 56 , 58 is provided connecting the bus controller 34 to two contacts 26 , which contacts 26 communicate the system memory controller 28 .
  • FIG. 2 a block diagram of the system of several memory modules 8 a, 8 b, and 8 c each having a DSP and two wire serial bus is shown.
  • the serial bus wires 56 , 58 are used for bus arbitration and the serial transfer of commands and data between the system memory controller 28 and the various modules 8 a, 8 b, 8 c.
  • a particular memory module 8 a, 8 b or 8 c needs to supply data to one of the devices on a bus, e.g.
  • the memory controller 34 for that module 8 a, 8 b or 8 c places its address on the control word line 56 of the serial bus.
  • the system memory controller 28 performs bus arbitration and either issues a grant on wire 58 or ignores the request. If the grant is issued, and it is for a write to the codec 32 , the memory bus controller 34 on the requesting memory module 8 a, 8 b or 8 c is programmed to format the required information and issues the command or control word on the wire 56 , followed by the address and required data in a form that can be received by the system memory controller 28 . These are all issued serially on the bus wire 56 .
  • the serial data is received and packeted by the system memory controller 28 , which, when completed, issues the commands, addresses and data on the bus on which the requesting device is located, e.g. on the PCI bus 30 for the codec 32 .
  • the requesting memory module remains in control of the serial bus and the request is relayed to the codec 32 which transfers the requested data and information to the system memory controller 28 which formats the data in a format suitable for transmission on the serial bus wires 56 , 58 , and then transfers the information to the requesting memory module.
  • the requesting memory module relinquishes the serial bus.
  • the PCI bus 30 will arbitrate when the codec 32 gets the bus, at which time the codec transfers the information on the PCI bus to the system memory controller 28 which then transfers the information to the designated memory module 8 a, 8 b or 8 c on the system memory bus rather than on the serial bus.
  • system memory controller 28 is receiving and packeting the serial data from the memory module on serial bus wire 56 , it is free to perform other tasks, including but not limited to, passing information on the memory address/control bus 16 and the memory data bus 18 with any one of the memory modules 8 including the module 8 a, 8 b or 8 c transmitting on its serial bus wire 56 .
  • the serial bus can act independently of the system bus and allow the DSP 36 on any of the memory modules 8 a, 8 b or 8 c be a bus master; and, this is accomplished without the need or requirement for one of the DSPs 36 to obtain control of the system bus.
  • FIG. 2 there are several memory modules 8 a, 8 b, and 8 c which contend for access, so in this case a controller is needed such as the memory controller 28 . If, however there is only one memory module 8 , and only slave device(s) on the bus where contention is not required, the serial bus wires 56 and 58 could be wired directly to the device(s) and the information transferred serially if each device is configured to receive serial information.
  • serial bus communicates with the system memory controller 28 , which in turn communicates with a PCI bus 30 on which the codec 32 is located.
  • PCI bus 30 on which the codec 32 is located.
  • other schemes could be employed.
  • busses than a PCI bus could be employed, or a controller other than the system memory controller 28 could be used to communicate with the memory modules 8 and control the bus on which a device is located.
  • other devices could be used.

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Abstract

A serial bus and connection to a device on a computer system through a system memory controller is provided on a memory card having a DSP and a memory bus controller to allow the DSP on the memory card to gain access to the system device without using the system memory bus. The serial bus is a two wire serial bus connecting the device to the DSP through the system memory controller. If more than one memory card is present with DSPs or more than one device is contending for access, the system memory controller or arbitrate the access of each memory card or contending device. In such case the serial bus will signal the system memory controller when it wants access to the particular device, and the system memory controller will act as arbitrator to grant or not grant access to the particular memory card or device requesting access. If access is granted the bus memory controller outputs the required control or command word on the serial bus followed by the address and the required data. This serial information is received by the system memory controller which packets it, and, upon completion, outputs the information rapidly on a parallel bus, e.g. a PCI bus to the device which needs the information.

Description

    BACKGROUND INFORMATION
  • 1. Field of the Invention [0001]
  • This invention relates generally to busses for memory cards to allow a Digital Signal Processor (DSP) on a memory DIMM or SIMM to communicate with a system memory controller, and more particularly to the use of a serial bus for communication of a DSP on a memory card with a system memory controller. [0002]
  • 2. Background Information [0003]
  • The use of DSPs on memory cards is now being proposed as a way for providing a relatively inexpensive processor on a memory card which can perform tasks on the card while the system bus is otherwise occupied. This works well in so far as it goes; i.e. as long as the DSP needs to be used only on the card on which it resides and does not need to communicate with the system bus this arrangement is fine. However with the present proposals there is no mechanism for the DSP on the card to initiate communication with the system bus and ultimately with devices controlled by the system bus. Since the DSP is a relative powerful processor it is desired that a technique be provided for a DSP to initiate communication effectively and simply with the system bus. [0004]
  • SUMMARY OF THE INVENTION
  • According to the present invention a serial bus and connection to a device on a computer system, preferably through a controller such as a system memory controller is provided on a memory card having a DSP and a memory bus controller to allow the DSP on the memory card to gain access to the device on the system bus without the need to use the system memory bus. The serial bus in its preferred form is a two wire serial bus which connects the device to the DSP through a memory bus controller and preferably through the system memory controller. If more than one memory card is present with DSPs or more than one device contending for access, the system memory controller or other controller will arbitrate the access of each memory card or contending device. In such case the serial bus will signal the system memory controller when it wants access to the particular device, and the system memory controller will act as arbitrator to grant or not grant access to the particular memory card or device requesting access. If access is granted the bus memory controller outputs the required control or command word on the serial bus followed by the address and the required data. This serial information is received by the system memory controller or some other controller which packets it, and, when the transmission is complete, outputs the information rapidly on a parallel bus, e.g. a PCI bus to the device which needs the information. Thus each DSP in effect becomes a bus master when so required for transferring data to and from a device other than the specific memory card on which it resides. The DSP can also take control for reading data from a device using the serial bus.[0005]
  • DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is diagram of a DIMM incorporating a DSP and memory bus controller and having a two wire serial bus communicating with a system memory controller; and [0006]
  • FIG. 2 is a block diagram or the connection of several memory modules to a system memory controller.[0007]
  • DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • Referring now to the drawings and for the present to FIG. 1, one embodiment of the present invention is shown as embodied in a [0008] personal computer 6. A memory module 8 such as a DIMM or SIMM is provided which includes a printed circuit card 10 having a plurality of synchronous DRAMs (SDRAMs) 12 a through 12 h. (It is to be understood that the number of the SDRAMs could be more or less, and that they can be arranged in one or more banks, as is well known in the art.) The synchronous DRAMs 12 a-12 h, which are conventional SDRAMS, are configured and arranged to store both data bits and check bits written to them by the computer system. The SDRAM's 12 a-12 h each have memory location 13 a-13 h reserved for a signal processing element which will be described presently. The circuit card 10 has a memory bus which includes a memory data bus 14 and a memory address/control bus 16; a system clock line 18, a wait line 20 and an interrupt request line 22 are also present. Memory data bus 14, memory address/control bus 16, system clock 18, wait line 20 and interrupt request line 22 are all connected to I/O connectors sometimes referred to as pins 26. The I/O connectors 26 provide an interface to a system memory controller 28, which is a part of the CPU or computer 6. The system memory controller 28 also controls a PCI bus 30 (and optionally other buses not shown). The PCI bus 30 has thereon devices such as a codec 32.
  • The [0009] memory card 10 also has a memory bus controller 34 which is connected to the memory data bus 14, the memory address/control bus 16, the system clock 18, the wait line 20, and the interrupt request line 22. The bus controller 34 is connected to a signal processing element 36 which in the preferred embodiment is a digital signal processor (DSP). A particularly useful DSP is any one of the TMS 320C54X family manufactured by Texas Instruments, Inc. This particular DSP family includes an external cache memory 38. The bus controller 34 and DSP 36 are interconnected by a chip address bus 40, a chip data bus 42 and control lines 44 that pass various control signals between the bus controller 34 and the DSP 36. This type of connection is well known in the art.
  • The [0010] memory data bus 14 has FET switches 50 therein. (It is to be understood that the memory data bus 14 is comprised of multiple lines, one for each bit and there is an FET 50 for each bit line.) The memory data bus 14 may be an 8 bit bus, a 16 bit bus, a 32 bit bus, or a 64 bit bus, and indeed any size data bus which includes whatever number of data lines are required. Also there are FET switches 52 in the system address/control bus 16. The system clock line 18 is also connected to the DSP 36 in the preferred embodiment; however, it is to be understood that a separate clock could be provided for the DSP if different timing is used on the card from the timing used in the CPU. However, the preferred embodiment for most instances is to use the system clock for clocking the functions and signals on the memory module.
  • A two wire serial bus, comprised of [0011] wires 56, 58 is provided connecting the bus controller 34 to two contacts 26, which contacts 26 communicate the system memory controller 28.
  • Many tasks of the DSP are accomplished when the memory module is not being addressed for either a read or write function or other function by the [0012] CPU memory controller 28. Thus the FETs 50 and 52 are in an open position when these tasks are taking place. If however, when the CPU wishes to access the memory module the FET's are closed and the memory controller 28 can address the memory module 8 on the memory data bus 14 and memory address/control bus 16 to perform conventional read/write operations from and to the SDRAMs 12 a-12 h.
  • Referring now to FIG. 2 a block diagram of the system of [0013] several memory modules 8 a, 8 b, and 8 c each having a DSP and two wire serial bus is shown. In this embodiment it is assumed that the different modules 8 a, 8 b and 8 c will be contending for access to the device(s) on the PCI bus. The serial bus wires 56, 58 are used for bus arbitration and the serial transfer of commands and data between the system memory controller 28 and the various modules 8 a, 8 b, 8 c. When a particular memory module 8 a, 8 b or 8 c needs to supply data to one of the devices on a bus, e.g. the codec 32 on the PCI bus 28, the memory controller 34 for that module 8 a, 8 b or 8 c places its address on the control word line 56 of the serial bus. The system memory controller 28 performs bus arbitration and either issues a grant on wire 58 or ignores the request. If the grant is issued, and it is for a write to the codec 32, the memory bus controller 34 on the requesting memory module 8 a, 8 b or 8 c is programmed to format the required information and issues the command or control word on the wire 56, followed by the address and required data in a form that can be received by the system memory controller 28. These are all issued serially on the bus wire 56. The serial data is received and packeted by the system memory controller 28, which, when completed, issues the commands, addresses and data on the bus on which the requesting device is located, e.g. on the PCI bus 30 for the codec 32.
  • If the request from the [0014] memory module 8 a, 8 b or 8 c is for a read, the requesting memory module remains in control of the serial bus and the request is relayed to the codec 32 which transfers the requested data and information to the system memory controller 28 which formats the data in a format suitable for transmission on the serial bus wires 56, 58, and then transfers the information to the requesting memory module. When the transfer is completed, the requesting memory module relinquishes the serial bus. If, however, the codec 32 initiates the request, the PCI bus 30 will arbitrate when the codec 32 gets the bus, at which time the codec transfers the information on the PCI bus to the system memory controller 28 which then transfers the information to the designated memory module 8 a, 8 b or 8 c on the system memory bus rather than on the serial bus.
  • It should be noted that while the [0015] system memory controller 28 is receiving and packeting the serial data from the memory module on serial bus wire 56, it is free to perform other tasks, including but not limited to, passing information on the memory address/control bus 16 and the memory data bus 18 with any one of the memory modules 8 including the module 8 a, 8 b or 8 c transmitting on its serial bus wire 56. Thus the serial bus can act independently of the system bus and allow the DSP 36 on any of the memory modules 8 a, 8 b or 8 c be a bus master; and, this is accomplished without the need or requirement for one of the DSPs 36 to obtain control of the system bus.
  • In the embodiment shown in FIG. 2 there are [0016] several memory modules 8 a, 8 b, and 8 c which contend for access, so in this case a controller is needed such as the memory controller 28. If, however there is only one memory module 8, and only slave device(s) on the bus where contention is not required, the serial bus wires 56 and 58 could be wired directly to the device(s) and the information transferred serially if each device is configured to receive serial information.
  • It should be noted that in the preferred embodiment the serial bus communicates with the [0017] system memory controller 28, which in turn communicates with a PCI bus 30 on which the codec 32 is located. However, other schemes could be employed. For example other busses than a PCI bus could be employed, or a controller other than the system memory controller 28 could be used to communicate with the memory modules 8 and control the bus on which a device is located. And, of course, other devices could be used.
  • Accordingly, the preferred embodiments of the present invention have been described. With the foregoing description in mind, however, it is understood that this description is made only by way of example, that the invention is not limited to the particular embodiments described herein, and that various rearrangements, modifications, and substitutions may be implemented without departing from the true spirit of the invention as hereinafter claimed. [0018]

Claims (18)

What is claimed is:
1. A memory module, comprising;
a memory card,
a signal processing element on said card,
a bus controller on said card,
memory storage chips on said card connected to said bus controller,
a memory bus connecting said signal processing element and said bus controller,
a parallel system bus connected to said memory controller, and
a serial bus distinct from said system bus connected to said processing element through said bus controller and to contacts on said card.
2. The invention as defined in claim 1 wherein said signal processing element is a digital signal processor.
3. The invention as defined in claim 1 wherein said serial bus is two wire bus.
4. The invention as defined in claim 1 further characterized by switches to selectively connect and disconnect the system bus and the bus controller.
5. A computer system including a parallel system bus and at least one memory module incorporated in the computer system comprising;
said at least one memory module including a memory card,
a signal processing element on said card,
a bus controller on said card,
memory storage chips on said card connected to said bus controller,
a memory bus connecting said signal processing element and said bus controller,
said parallel system bus connected to said bus controller,
a serial bus distinct from said system bus connected to said processing element through said bus controller and to contacts on said card, and
at least one device operatively connected to said serial bus through said contacts on said card.
6. The invention as defined in claim 5 wherein each said device is on a bus in said system.
7. The invention as defined in claim 6 wherein said serial bus connects to said device through a controller.
8. The invention as defined in claim 6 wherein said bus within said system is connected to a system bus through a system memory controller.
9. The invention as defined in claim 7 wherein said serial bus connects to said device through said system memory controller.
10. The invention as defined in claim 8 wherein there are a plurality of said memory modules incorporated in said computer system.
11. The invention as defined in claim 8 wherein said controller arbitrates access to said at least one device.
12. The invention as defined in claim 6 wherein said at least one device is a codec.
13. A method of passing data between at least one device in a computer system and a signal processing element connected to a bus controller on at least one memory module incorporated in the computer system, wherein said computer system has a system parallel bus communicating with said bus controller, comprising the steps of;
providing a serial bus distinct from said system bus operatively connecting said bus controller and said at least one device, and
passing serial information on said serial bus.
14. The invention as defined in claim 13 wherein said serial bus is connected to said at least one device through a controller.
15. The invention as defined in claim 14 wherein said controller is a system memory controller.
16. The invention as defined in claim 14 wherein said at least on device is on a bus in the computer system.
17. The invention as defined in claim 16 wherein the bus on which said one device is located is a parallel bus, and said controller converts serial information to parallel information for delivery to said one device.
18. The invention as defined in claim 14 wherein there are a plurality of said memory modules incorporated in the computer system, and wherein said controller arbitrates access to said serial bus.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2857474A1 (en) * 2003-07-10 2005-01-14 Jetcaps Europ Computer device e.g. central unit, memory expansion device, has memory strip assembled at memory expansion location of motherboard of computer device, and port to establish series connection from motherboard to another device

Families Citing this family (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7734852B1 (en) * 1998-08-06 2010-06-08 Ahern Frank W Modular computer system
US6446163B1 (en) * 1999-01-04 2002-09-03 International Business Machines Corporation Memory card with signal processing element
US6594719B1 (en) 2000-04-19 2003-07-15 Mobility Electronics Inc. Extended cardbus/pc card controller with split-bridge ™technology
US20060288141A1 (en) * 2000-04-19 2006-12-21 Ahern Frank W Modular computer
US20040030952A1 (en) * 2000-09-29 2004-02-12 Piccirillo Gary J. Rambus based hot plug memory
US20040133720A1 (en) * 2002-12-31 2004-07-08 Steven Slupsky Embeddable single board computer
US7386639B2 (en) * 2003-01-15 2008-06-10 Avago Technologies Fiber Ip (Singapore) Pte. Ltd. Switch for coupling one bus to another bus
US20050038958A1 (en) * 2003-08-13 2005-02-17 Mike Jadon Disk-array controller with host-controlled NVRAM
US7293197B2 (en) * 2003-08-13 2007-11-06 Micro Memory Llc Non-volatile memory with network fail-over
US7539800B2 (en) * 2004-07-30 2009-05-26 International Business Machines Corporation System, method and storage medium for providing segment level sparing
US7389375B2 (en) 2004-07-30 2008-06-17 International Business Machines Corporation System, method and storage medium for a multi-mode memory buffer device
US7296129B2 (en) 2004-07-30 2007-11-13 International Business Machines Corporation System, method and storage medium for providing a serialized memory interface with a bus repeater
US20060036826A1 (en) * 2004-07-30 2006-02-16 International Business Machines Corporation System, method and storage medium for providing a bus speed multiplier
US7512762B2 (en) 2004-10-29 2009-03-31 International Business Machines Corporation System, method and storage medium for a memory subsystem with positional read data latency
US7305574B2 (en) 2004-10-29 2007-12-04 International Business Machines Corporation System, method and storage medium for bus calibration in a memory subsystem
US7331010B2 (en) 2004-10-29 2008-02-12 International Business Machines Corporation System, method and storage medium for providing fault detection and correction in a memory subsystem
US7299313B2 (en) 2004-10-29 2007-11-20 International Business Machines Corporation System, method and storage medium for a memory subsystem command interface
US7441060B2 (en) 2004-10-29 2008-10-21 International Business Machines Corporation System, method and storage medium for providing a service interface to a memory system
US7478259B2 (en) 2005-10-31 2009-01-13 International Business Machines Corporation System, method and storage medium for deriving clocks in a memory system
US7685392B2 (en) 2005-11-28 2010-03-23 International Business Machines Corporation Providing indeterminate read data latency in a memory system
US7636813B2 (en) * 2006-05-22 2009-12-22 International Business Machines Corporation Systems and methods for providing remote pre-fetch buffers
US7594055B2 (en) * 2006-05-24 2009-09-22 International Business Machines Corporation Systems and methods for providing distributed technology independent memory controllers
US7640386B2 (en) 2006-05-24 2009-12-29 International Business Machines Corporation Systems and methods for providing memory modules with multiple hub devices
US7584336B2 (en) * 2006-06-08 2009-09-01 International Business Machines Corporation Systems and methods for providing data modification operations in memory subsystems
US7669086B2 (en) 2006-08-02 2010-02-23 International Business Machines Corporation Systems and methods for providing collision detection in a memory system
US7581073B2 (en) * 2006-08-09 2009-08-25 International Business Machines Corporation Systems and methods for providing distributed autonomous power management in a memory system
US7587559B2 (en) 2006-08-10 2009-09-08 International Business Machines Corporation Systems and methods for memory module power management
US7539842B2 (en) 2006-08-15 2009-05-26 International Business Machines Corporation Computer memory system for selecting memory buses according to physical memory organization information stored in virtual address translation tables
US7870459B2 (en) 2006-10-23 2011-01-11 International Business Machines Corporation High density high reliability memory module with power gating and a fault tolerant address and command bus
US7752364B2 (en) * 2006-12-06 2010-07-06 Mosaid Technologies Incorporated Apparatus and method for communicating with semiconductor devices of a serial interconnection
US7721140B2 (en) 2007-01-02 2010-05-18 International Business Machines Corporation Systems and methods for improving serviceability of a memory system
US7606988B2 (en) * 2007-01-29 2009-10-20 International Business Machines Corporation Systems and methods for providing a dynamic memory bank page policy
US7603526B2 (en) 2007-01-29 2009-10-13 International Business Machines Corporation Systems and methods for providing dynamic memory pre-fetch

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4885538A (en) * 1988-08-19 1989-12-05 The Regents Of The University Of California Low data rate low noise serial digital communication link for magnetic resonance imaging systems
CA2069711C (en) 1991-09-18 1999-11-30 Donald Edward Carmon Multi-media signal processor computer system
US5519839A (en) 1992-10-02 1996-05-21 Compaq Computer Corp. Double buffering operations between the memory bus and the expansion bus of a computer system
US5440740A (en) 1992-10-13 1995-08-08 Chen; Fetchi System and method for managing devices on multiple digital signal processors
US5450551A (en) 1993-05-28 1995-09-12 International Business Machines Corporation System direct memory access (DMA) support logic for PCI based computer system
EP0654743A1 (en) 1993-11-19 1995-05-24 International Business Machines Corporation Computer system having a DSP local bus
US5739850A (en) * 1993-11-30 1998-04-14 Canon Kabushiki Kaisha Apparatus for improving the image and sound processing capabilities of a camera
US5546547A (en) 1994-01-28 1996-08-13 Apple Computer, Inc. Memory bus arbiter for a computer system having a dsp co-processor
US5557757A (en) 1994-02-02 1996-09-17 Advanced Micro Devices High performance integrated processor architecture including a sub-bus control unit for generating signals to control a secondary, non-multiplexed external bus
US5600845A (en) * 1994-07-27 1997-02-04 Metalithic Systems Incorporated Integrated circuit computing device comprising a dynamically configurable gate array having a microprocessor and reconfigurable instruction execution means and method therefor
US5692211A (en) 1995-09-11 1997-11-25 Advanced Micro Devices, Inc. Computer system and method having a dedicated multimedia engine and including separate command and data paths
US5928347A (en) * 1997-11-18 1999-07-27 Shuttle Technology Group Ltd. Universal memory card interface apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2857474A1 (en) * 2003-07-10 2005-01-14 Jetcaps Europ Computer device e.g. central unit, memory expansion device, has memory strip assembled at memory expansion location of motherboard of computer device, and port to establish series connection from motherboard to another device

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