Abstract:
An interface connection is described for joining a host device, such as a Network Processor, to peripherals such as modems, printers, local area networks, Ethernets and Token-Ring interfaces. The connection is particularly useful for joining portable computers, such as laptops, to these peripherals. The connector utilizes a programmable Network Processor (NP) either in the host device or in an external fan-out box. This programmable Network Processor adapts the host device to a variety of peripheral devices utilizing different protocols and I/O speeds. The NP can use a Digital Signal Processor to provide programmable services to the physical layers. The host device may contain a high-speed communication interface with the NP contained in the external connection box.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates to interface connections between electronic devices, such as personal computers and peripherals, that are used with the devices. More particularly, the invention relates to a universal physical interconnection interface including associated connector(s), interface technology and common software drivers.  
           [0003]    2. Discussion of Related Art  
           [0004]    The development of an ever-increasing number of physical interconnection interfaces for personal computers and networking equipment causes communication product developers tremendously difficult problems. Two examples will suffice to illustrate the point.  
           [0005]    1. One of the most attractive attributes of a PC is its expandability to include modems, graphic accelerators, CD-ROM drives, scanners, video cameras, printers, disk drives and others. A defining element of the physical characteristics of a PC, such as a laptop computer, is the large number of connectors that are required to accommodate these internal and external devices. The numerous connectors require unique physical layer (generally analog) technology to interface with each connector and specific logic functions to interface with the analog technology. These logic functions are called the MAC (Media Access Control) layer functions.  
           [0006]    2. For a manufacturer of communications equipment, generally there are a multitude of physical layer interfaces that must be supported. A particular product may require different interface versions to support 10/100 Mbps Ethernet, 16 Mbps Token-Ring, 1 Gbps Ethernet and 1 Gbps Fiber Channel, in addition to the numerous devices mentioned above. The problem, however, goes beyond the physical connectors to the MAC layer, where each interface requires its unique MAC layer support. Thus, in order for a universal connection scheme to work, it must be able to satisfy interoperability requirements with many physical layer communication standards and common I/O device standards.  
           [0007]    Several related art patents and publications are summarized in the following discussion.  
           [0008]    U.S. Pat. No. 5,539,666 Data Communications Method and System Coupling Device: This patent is relates to a data communication method and a system-coupling device. The data communication method preferably is used for serial communication wherein a bus of a computer system is coupled to a bus of an extension box or a bus of another computer system via a signal transmission path. A predetermined code system and data transfer scheme is defined that permits asynchronous interruption of a lower priority data transmission whenever a higher priority data transmission is required. Serial optical-fiber links are assumed to exist between the sending and receiving units.  
           [0009]    U.S. Pat. No. 5,627,728 Expansion Box for Notebook Computers: This patent describes the physical design of an expansion box that physically mounts to the underside of a matching notebook computer. The expansion box contains the physical means for attaching modular expansion units (e.g., cartridges or cards). Each cartridge or card includes a connector for mating with a corresponding unit connector of the expansion board. The description of the preferred embodiment allows for the expansion box to reside separate from the notebook computer via a cable link rather than to be physically attached to the notebook computer. The patent does not address the functionality of the expansion units or the interface means that are incorporated within the expansion units, or between the expansion unit(s) and the system motherboard.  
           [0010]    U.S. Pat. No. 5,729,478 Notebook Computer with Insertable Expansion Devices: This patent describes a design and method for attaching expansion units to a notebook computer. The design provides an “expansion notch” with connector to the system motherboard whereby the expansion unit(s) are designed to fit within the notch rather than protrude externally, thus minimizing the footprint of the overall unit when the expansion unit is installed. It does not address the functionality of the expansion units or the interface means that are incorporated within the expansion units, or between the expansion unit and the system motherboard.  
           [0011]    U.S. Pat. No. 5,984,731 Removable 1/O Device with Integrated Receptacles for Receiving Standard Plugs: This patent describes the physical design of a Type III PCMCIA adapter that contains a plurality of wired-network interface ports (RJ-type form factor). The electrical characteristics and physical form and dimensions are described.  
           [0012]    U.S. Pat. No. 6,006,295 Translator with Selectable FIFO for Universal Hub Cables for Connecting a PC&#39;s PCMCIA or Parallel Ports to Various Peripherals Using IDE/ATAPI, SCSI, or General I/O: This patent is related to personal computers and, more particularly, to multi-use cables for connecting external devices to a personal computer. A universal cable set is described that includes a built-in translator device as part of the cable that allows the parallel port or PCMCIA adapter within a computer to attach to a plurality of devices, such as IDE/ATAPI, SCSI or other general I/O interfaces. It states that “A programmable means in the translator converts the parallel port signals into external interface signals for an integrated-device-electronics IDE interface, or into external interface signals for a small-computer-systems-interface.” A software program executing in the PC transmits configuration information to the translator. The housing for the translator also contains a parallel printer port connector. A second cable of similar design contains a PCMCIA (Personal Computed Memory Card International Association) connector.  
           [0013]    U.S. Pat. No. 6,070,199 Apparatus to Connect a Client Computer to a Computer Data Network: This patent describes a network interface device that utilizes an infrared link between a laptop computer and a wired-LAN interconnect unit. The communication software drivers within the computer provide a transparent link that appears as a direct-wired link to the computer applications. The interconnect unit contains the wired-LAN network interface card (NIC), such as a 10 Mbps Ethernet link. It also provides packet-filtering functions to forward only those packets that are destined for the computer via the infrared link.  
           [0014]    U.S. Pat. No. 6,159,022 Universal Electrical Connector Station: This patent describes a specific mechanical and physical design for a universal electrical station, consisting of an enclosure, an electrical circuit board, and several external physical connections of multiple devices to a notebook computer. The design utilizes all four sides of the enclosure for physical connectors. This patent is associated with the physical design of a specific embodiment. It does not describe a specific design for an enclosure or circuit board, nor does it address software driver issues.  
           [0015]    IBM 41082 Disclosure Publication, Dynamic Switching Between Different LAN Networking Media: This disclosure publication describes a universal software driver for interfacing a networking application to a plurality of physical media types (Ethernet, infrared, radio frequency, etc.). The basic concept is that a single, universal driver presents a common interface to the higher layer network applications while allowing the user to select the most convenient network interface link. The universal driver appears to be an Ethernet link to the network application, yet the actual transmission link may or may not be Ethernet.  
           [0016]    IBM Dossier RPS920000078, Widescreen Notebook Input/Output Device Interface: This disclosure relates to an enhanced design of a laptop computer that includes an extended (e.g., wider) keyboard and display. The extended keyboard provides a recessed area and connector for incorporating pluggable enhancement modules or I/O devices. A plurality of devices are supported. The system is plug and play in that when an I/O device is plugged into the universal I/O connector, it may be automatically sensed by circuitry internal to the notebook computer and software drivers are loaded that enable the particular I/O device to be used.  
         BRIEF DESCRIPTION OF THE INVENTION  
         [0017]    One object of the present invention is incorporating a programmable Network Processor (NP) into an external fan-out box to provide broader flexibility in adapting to a variety of device types.  
           [0018]    Another object is the incorporation of a programmable Network Processor within a laptop computer to allow flexible attachment of multiple device types, either with or without an external fan-out box.  
           [0019]    Still another object is the use of a programmable Network Processor device to handle the Media Access Control layer functions for a plurality of I/O types and speeds.  
           [0020]    Yet another object is the extension of protocol support within a programmable Network Processor to MAC layer and layer  3  network protocols.  
           [0021]    Further, it is an object to incorporate programmable digital signal processor elements within the programmable Network Processor to provide more flexibility in the physical interface attachments that can be currently supported.  
           [0022]    These, as well as other objects and advantages, will become more readily understandable in light of the discussion that follows.  
           [0023]    The present invention relates to a universal connection system that satisfies these interoperability requirements in a simple yet effective manner.  
           [0024]    The invention relates to a computer system and its method of use wherein the system is composed of an electronic device and one or more peripherals associated with the device. A universal interface joins the device to each peripheral and uses a programmable Network Processor for handling the I/O between the device and each peripheral. The NP includes capabilities for handling multiple peripherals and a plurality of I/O speeds. It is incorporated into a fan-out box external to the electronic device or may be incorporated into the device itself, particularly where the device is a laptop computer. The NP may include support to MAC layer and layer  3  network protocols. The NP may also utilize or incorporate a programmable Digital Signal Processor. The system furthermore can support an Ethernet MAC format or any other suitable communications protocol for the flow of information between the electronic device and the peripherals. When the device is a laptop computer, it may include a high-speed communication interface with the NP contained in an external connection box.  
           [0025]    The invention also relates to a universal interface connection for joining a plurality of peripherals to a portable computer. The connection includes a programmable Network Processor which may include the capabilities for handing a plurality of I/O speeds. The connection also includes a cable connecting the computer to the peripherals. A subsystem in the NP serves to translate I/O information into an output format to be sent by the cable for each peripheral. The NP either is incorporated into a fan-out box external to the electronic device or, if the electronic device is a laptop computer, may be included within the laptop computer. The NP may include support to layer  2  (MAC) protocols and layer  3  network protocols. The NP may also include a programmable digital signal processor.  
           [0026]    For purposes of clarification, the following abbreviations when used hereinafter, will relate to the following components, systems or functions.  
           [0027]    ATM means Asynchronous Transfer Mode.  
           [0028]    DSP is a Digital Signal Processor. This is a high-speed coprocessor designed to do real-time manipulation of analog signals. It is described in a BDTI White Paper entitled THE EVOLUTION OF DSP PROCESSORS, by Jennifer Eyre and Jeff Bier, Berkeley Design Technology, Inc, 2000. Also, see www.bdti.com. or www.ti.com and go to DSP DEVELOPERS VILLAGE and look up “What is DSP”.  
           [0029]    Ethernet is a 10 Mbps or 100 Mbps baseband local area network (LAN) that allows multiple stations to access transmission medium at will without prior coordination. It is specified in the IEEE 802.3 Standards, the contents of which are incorporated herein by reference.  
           [0030]    FCS is a Frame Check Sequence. This is a character or a field used for the detection of transmission errors.  
           [0031]    GBEN Stands for Gigabit Ethernet  
           [0032]    IP is Internet Protocol that is used to route data from its source to its destination in an internet environment.  
           [0033]    LAN stands for Local Area Network comprising a computer network used to connect personal computers, workstations, printers and other peripherals within a limited geographical area, such as a single building or building complex.  
           [0034]    MAC layer is a Media Access Control layer. For details of the design and operation, see Stallings, DATA AND COMPUTER COMMUNICATIONS, 2 nd  Ed., page 10; or IEEE 802.3 and 802.5  
           [0035]    PCMCIA stands for Personal Computer Memory Card International Association. It establishes standards including electrical and physical specifications for cards that are removably engaged with the sockets or slots of computers and peripherals.  
           [0036]    PDU is a Protocol Data Unit, which is a unit of data specified in a protocol of a given layer. It consists of protocol control information and possibly user data from the next higher layer.  
           [0037]    NP is a programmable Network Processor, the programming of which can be changed by the operator. A software program suitable in the teachings of the present invention can be written by any person skilled in the art. Except to the extent that the program interfaces with the other components and steps of providing a universal interface connection, it does not comprise a portion of the present invention.  
           [0038]    Token-Ring is a network with a star topology that uses a procedure for passing tokens from one attaching device to another.  
           [0039]    USB is Universal Serial Bus connector. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0040]    [0040]FIG. 1 is a block diagram showing one embodiment of the present invention;  
         [0041]    [0041]FIG. 2 is a block diagram of another embodiment; and  
         [0042]    [0042]FIG. 3 shows logic and circuit elements of the Network Processor useful in the teachings of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0043]    This invention relates to the application of an NP that overcomes the problems associated with the expanding number of physical and logical interconnection interfaces.  
         [0044]    The first problem of multiple connectors in a PC is addressed by defining a universal connector (which could be unique, or it may be one that is already used on the machine type in question). One embodiment requires, for each type of device to be supported, the development of a transition cable to provide the physical connector that a particular device normally connects to, such as in PCMCIA connector technology. Thus, an SCSI cable may be used to connect an SCSI disk drive to the PC; an IDE cable is used with an IDE hard drive; a printer cable for hooking up a printer, etc. Heretofore, the number of connectors required in the box has been somewhat reduced, thereby reducing the form factor of the product, a clear goal for laptop products, such as ThinkPad. However, as previously noted, this requires that a number of transition cables be made available as options for the user. Behind the connector in the box lies the analog logic followed by an NP. The main thrust here is that the NP is programmed to support the necessary interfaces.  
         [0045]    Referring now to FIG. 1, a short cable joins a fan-out box to the universal connector in the laptop. This fan-out box houses an NP and handles the MAC (Media Access Control) layer functions for each of the product interfaces that are supported. It also multiplexes the traffic from the fan-out box, over the new interface, back to the laptop, where another NP demultiplexes the data and interfaces with the processor subsystem. In this configuration, if the user was mobile and did not need the many interfaces provided by the fan-out box, the single device can be attached via the universal interface in the laptop, and the NP inside the laptop then provides the MAC layer functions.  
         [0046]    The drawing shows a laptop computer  110  and a connector box  112 . A USB (universal serial bus)  114  on the laptop  110  is joined to a corresponding USB  116  on the connector box  112  by a suitable two way cable  118 . Within the computer  110  is a logical interface delivering either printer packets  120  or network packets  122  to the Network Processor  124 . The Network Processor is coupled to the laptop USB  114 . The connector box  112  contains a Network Processor  130  which handles the MAC layer processing. Also included within the connector box  112  are a plurality of I/O physical interfaces joined to their matching connector ports. Phy 1   132  is joined to USB connector port  134 ; Phy 2   136  is joined to Ethernet 10/100 connector port  138 ; Phy 3   140  is connected to Token-Ring connector port  142 ; Phy 4   144  is connected to a 1 Gbps Ethernet connector port  146 , Phy 5   148  is joined to a 1 Gbps fiber connector port  150  and PhyX  152  is joined to connector port X  154 . In the case of a manufacturer who has many different MAC layer interfaces to support, the NP can be used as a programmable MAC device. This arrangement serves to reduce the requirement to have, for example, 10/100 Mbps, 1 Gbps Ethernet, and 16 Mbps Token-Ring MAC layer devices in inventory. It also reduces the development time since board layout is simplified.  
         [0047]    The programmable Network Processor implementation for attaching a variety of media types can also be extended to simplify the software drivers required in the host station. For example, Ethernet and Token-Ring have different frame formats and, thus, require unique software drivers to interface to higher-layer protocols. These drivers are responsible for building the full frame, including MAC-level headers, for outbound frames, as well as removing the MAC-level headers for inbound frames. The NP is capable of isolating the higher-layer software applications within the host from the MAC-level driver functions by providing the “intelligence” required to perform the basic driver functions. The NP-to-host internal interface can thus be a ‘generic’ interface for exchanging only the so-called Protocol Data Unit (PDU) minus the MAC-level headers. Thus, inbound traffic may reach the NP with Ethernet, Token-Ring or other MAC-level headers, which are stripped off prior to passing only the PDU information to the host. The NP also verifies the MAC-level frame to be error-free through the Frame Check Sequence (FCS) operation prior to removing the MAC header. Likewise, the MAC header and FCS information are appended to the basic PDU prior to transmission on either media type.  
         [0048]    This functionality can also be extended to the Layer  3  Internet Protocol (IP) header processing. The IBM PowerNP® Network Processor, for example, can provide basic IP frame header manipulation for both inbound and outbound traffic. These functions may include:  
         [0049]    Layer  3  Firewall function that filters traffic from reaching the host (based on IP header contents)  
         [0050]    IP checksum validation (offloads host processing)  
         [0051]    IP forwarding/rerouting (allow host to redirect traffic if necessary)  
         [0052]    A second aspect of the invention, as illustrated in FIG. 2, addresses an alternative approach whereby a single, high-speed communications interface is used in the host (e.g. a laptop computer) to send and receive all I/O traffic addressed to external devices and/or network connections. For simplification, the last two digits of the reference numbers refer to similar components in the drawings. The drawing shows a laptop computer  210  and a connector box  212 . Within the computer  210  is a printer packet GBEN MAC  264  with a line  266  leading to a host PCI bus. The GBEN MAC  264  is joined to GBEN  260  that communicates through a high-speed interface  270  with GBEN  262  on the connector box  212 . As in FIG. 1, the connector box  212  contains a Network Processor  230  which handles the MAC layer processor. Included within the connector box  212  are a plurality of physical layers joined to their matching connector ports. Phy 1   232  is joined to USB connector port  234 ; Phy 2   226  is joined to Ethernet 10/100 connector port  238 ; Phy 3   240  is connected to Token-Ring connector port  242 ; Phy 4   244  is connected to a 1 Gbps Ethernet connector port  246 ; Phy 5   248  is joined to a 1 Gbps fiber connector port  250 , and PhyX  252  is joined to connector X port  254 . In this case, the software in the host system communicates with all external devices using layer  2  headers and packetized data. The Network Processor  230  in the Connector Box converts packets sent from the host into the appropriate MAC format for the target I/O device and routes the data to the appropriate connector port. A Digital Signal Processor inside the NP also formats the raw data into an appropriate bit stream to match the physical layer signaling requirements of the standard device interface, i.e. parallel, serial, USB, Ethernet, Token-Ring, etc. This embodiment provides the advantages of a single software interface and a single, standard, high-speed communications interface.  
         [0053]    The application of the programmable Network Processor to provide a MAC interface for communications ports with different physical interfaces, i.e. Ethernet and Token-Ring, can be extended to many other I/O ports. There are several benefits to this approach, one of which is that a single software interface or hardware abstraction layer can be defined to cover data movement and control between the host and all I/O ports in the system. More details concerning hardware abstraction layers can be found at http://msdn.microsoft.com.  
         [0054]    The I/O ports used as examples in this invention, e.g. Token-Ring, Ethernet, xDSL, FDDI, ATM, USB, Modem, Legacy Serial and Legacy Parallel, each have different data formatting requirements at the MAC layer and different signaling requirements at the physical interface between the host and the specific I/O connection. The architecture of a Network Processor allows co-processing attachments to enhance processing speed and function. One or more Digital Signal Processors are added, either embedded or attached through an external co-processing bus, to the core of the Network Processor and are used to provide programmable physical layer services. One such service is the Fast Link Pulse signaling used for Auto-Negotiation between Ethernet Phy devices. The signaling convention defined by this standard allows different speed Ethernet devices, i.e. 10 Mbps and 100 Mbps, to attach to the same physical port. Provided that there is some signaling convention defined to allow the host interface to detect the attachment and characteristics of the I/O device, then the NP with DSP can automatically configure itself to communicate with that device.  
         [0055]    More than one DSP or a multi-ported DSP can be added to handle concurrent operations to multiple I/O ports. Other signaling services can be programmed into the DSP as they become standardized, including Plug&#39;n Play, allowing OEM companies to support new I/O interfaces as soon as they are defined by the industry, independent of application specific hardware activity.  
         [0056]    [0056]FIG. 3 shows the connector box  312  with high level view of a programmable Network Processor  330 , as well as the circuit elements required to connect a DSP interface  370  to a specific I/O port and to provide the correct transceiver signal characteristics, i.e. power and voltage transitions. Shown within the Network Processor  330  are an input data flow  372 , an output data flow  374  and a plurality of I/O packet processors  376 . The Network Processor  330  is connected to the I/O physical interface  380  through a plurality of wires  382 . The interface  380  in joined through gates  384  and a plurality of connectors  386  to a plurality of devices  390  which, for purposes of illustration, are a Token-Ring, Ethernet, USB, ATM, FDDI, and RS232C serial interface ports.  
         [0057]    While the invention has been described in combination with embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing teachings. Accordingly, the invention is intended to embrace all such alternatives, modifications and variations as fall within the spirit and scope of the appended claims.