Abstract:
Customer requirements for portable computers are grouped into logical functional groupings, which are further grouped into logical bandwidth levels. On the notebook side, all required signals for a specific logical functional grouping are combined into a single carrier with the necessary bandwidth for the signals within the logical bandwidth level. This combined signal is then passed through a docking connector. The individual signals are regenerated on the docking solution side of the connector. Logic on both the notebook and docking solution sides of the connector enables the respective devices to identify which carrier bandwidths are supported on both sides of the docking connector and settle on the greatest common denominator. Additionally, the signals combined into the carrier can be programmed, in which case the docking solution and the notebook negotiate the features that are and are not supported in each individual case.

Description:
BACKGROUND  
         [0001]    The disclosures herein relate generally to portable computers and, more particularly, to a scalable architecture for portable computer docking stations.  
           [0002]    USB docking device class integrated circuit (“IC”) logic, as fully described in detail in related U.S. patent application Ser. No. ______ (Atty. Docket No. DC-02620) entitled “USB DOCKING DEVICE CLASS IC”, filed ______ and hereby incorporated by reference in its entirety, disposed on both sides of the connector enables the notebook and the docking solution to identify which carrier bandwidths are supported on both sides of the docking connector and settle on the greatest common denominator. Additionally, the signals combined on the single carrier can be programmed, in which case the docking solution and the notebook negotiate the features that are and are not supported in each individual case.  
           [0003]    Docking solutions for portable computers, or “notebooks”, are intended to perform several functions. Specifically, such solutions should provide cable management by replicating existing notebook functions and ports, add additional functionality, such as networking, SCSI ports, and a media bay, and enable users to add functionality, typically via PCI bus slots or PC card slots. The design generally used to accomplish these functions is to pass all necessary signals individually across a docking connector and into the docking solution.  
           [0004]    The problem with this design methodology is that it is specific to each notebook and docking solution design pair. Each time a new notebook is designed, a decision must be made as to what features will be included in the notebook, the docking solution, and both. Hardware and software must then be developed to implement the required features. Another problem associated with this design methodology is that it requires a very large number of signals, some with different requirements, to be passed along a single docking connector. From a customer perspective, the above means that each time a new notebook is purchased, a new docking solution often must be purchased along with it.  
           [0005]    The above-described problems have been mitigated by some manufacturers by their fixing docking solution architecture for all notebooks and docking solutions within a notebook family. For example, Dell Computer Corporation (“Dell”) has fixed the docking solution architecture for all of its notebooks and docking stations since the introduction of the Latitude CP. In doing so, Dell has been able to leverage the development work done with the original C-Family design. This approach enables forward/backward compatibility, as well as compatibility up and down product lines; however, it has limited development to features and compromises that were in the initial docking solution design.  
           [0006]    Further, to maintain docking commonality, notebooks targeted at different markets from performance to basic low-cost are limited by the features of the docking architecture or compromised by the cost impact of the docking architecture, respectively.  
           [0007]    Therefore, what is needed is a scalable docking architecture for portable computers that does not necessitate the aforementioned compromises to be made in the docking solution.  
         SUMMARY  
         [0008]    One embodiment, accordingly, is a scalable docking architecture for portable computers. Customer requirements for portable computers are grouped into logical functional groupings, which are further grouped into logical bandwidth levels. On the notebook side, all required signals for a specific logical functional grouping are combined into a single carrier with the necessary bandwidth for the signals within the logical bandwidth level. This combined signal is then passed through a docking connector. The individual signals are regenerated on the docking solution side of the connector.  
           [0009]    A principle advantage of the embodiments is that, by enabling multiple bandwidths, products targeted at more cost-sensitive markets need not be compromised with the cost associated with unnecessary functionality, while products targeted at high-end markets not limited to the “mainstream” balance of features and cost. Moreover, new products can add additional features while maintaining forward and backward compatibility between notebook and docking solutions. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    [0010]FIG. 1A is a table illustrating examples of potential notebook/dock groupings and bandwidth levels.  
         [0011]    [0011]FIG. 1B is a block diagram of a potential implementation using the groupings illustrated in the table of FIG. 1A.  
         [0012]    FIGS.  2 A- 2 E are system block diagrams of notebook/dock combinations embodying features of one embodiment.  
         [0013]    [0013]FIG. 3 is a system block diagram of a notebook/dock combination embodying a power-saving feature of one embodiment. 
     
    
     DETAILED DESCRIPTION  
       [0014]    [0014]FIG. 1A is a table (“Table I”) illustrating potential logical groupings and bandwidth levels of one embodiment. In particular, as shown in Table I, a first logical, or functional, grouping, referred to as “Simple Port Replication”, encompasses the following customer required functions: replication of all ports on the notebook; communications functions; and required docking control sidebands. The bandwidth level of this functional grouping is “Low,” defined in the illustrated embodiment as 5 megabytes/second (“Mbytes/s”). A second functional grouping, referred to as “PCI Docking”, encompasses the following customer required functions: PCI bus; and IEEE1394 bus. The bandwidth level of this functional grouping is “Medium,” defined in the illustrated embodiment as 500 Mbytes/s. A third functional grouping, referred to as “Desktop Replacement”, encompasses the following customer required functions: Advanced Graphics Processor (“AGP”) bus; and gigabit Ethernet. The bandwidth level of this functional grouping is “High,” defined in the illustrated embodiment as 5 gigabytes/second (“Gbytes/s”). The bandwidth levels represent the maximum bandwidth supported within the level.  
         [0015]    It should be noted that the bandwidth levels defined in FIG. 1A are illustrative only and that greater or fewer than three such levels may be defined as necessary. Moreover, the definitions of the levels themselves may be altered (e.g., “Low” could be defined as 500 Mbits/s; “Medium” could be defined as 300 Mbytes/s).  
         [0016]    [0016]FIG. 1B illustrates a potential implementation of the definitions set forth in FIG. 1A. FIG. 1B illustrates three notebooks  100   a,    100   b,    100   c,  having different performance levels. Specifically, the notebook  100   a  is a high performance, or “high-end”, system; the notebook  100   b  is a mid-level performance, or “mainstream”, system; the notebook  100   c  is a basic, or “low-end”, system. Applying the functional groupings set forth in FIG. 1A, the notebooks  100   a,    100   b,  and  100   c,  are placed in the “Desktop Replacement Docking,” “Traditional PCI Docking,” and “Simple Port Replication” groupings, respectively. Two types of docks are represented in FIG. 1B, including a high-end dock  102   a  consisting of a full dock with an AGP 8× slot and a low-end dock  102   b  consisting of simple port replication with an optional media bay. In accordance with features of one embodiment, as described in greater detail below, any of the notebooks  100   a,    100   b,    100   c,  could be docked to the low-end dock  102   b.  Additionally, the notebook  100   c  could be advantageously docked to the high-end dock  102   a.  If, for example, the low-end notebook  100   c  were connected to the high-end dock  102   a,  the features of the docking station that are supported by the notebook would work; other features of the docking station would not work.  
         [0017]    [0017]FIGS. 2A, 2B, and  2 C are block diagrams representing various configurations of notebooks and docking stations according to one embodiment. Referring to FIG. 2A, a notebook  200   a  includes a plurality of buses encompassing three “bandwidth levels”, as defined with reference to FIG. 1A. In particular, the notebook  200   a  includes one or more high bandwidth level buses, represented by a bus  202   a,  one or more medium bandwidth level buses, represented by a bus  204   a,  and one or more low bandwidth level buses, represented by a bus  206   a.  Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems of the notebook  200   a,  collectively designated by a reference numeral  207   a,  in a conventional fashion. The buses  202   a,    204   a,  and  206   a,  are connected to a docking connector  208   a  of the notebook  200   a  via a logic interface  210   a,  the function of which will be described in detail below.  
         [0018]    The docking connector  208   a  is designed to mate with a complementary docking connector  214   a  disposed on a dock  216   a.  The dock  216   a  includes one or more high bandwidth level buses, represented by a bus  218   a,  one or more medium bandwidth level buses, represented by a bus  220   a,  and one or more low bandwidth level buses, represented by a bus  222   a.  Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems connected to and disposed on and within the dock  216   a,  collectively designated by a reference numeral  223   a,  in a conventional fashion. The buses  218   a,    220   a,  and  222   a,  are connected to the docking connector  214   a  of the dock  216   a  via a logic interface  226   a,  the function of which will be described in detail below.  
         [0019]    In general, the function of the logic interface  210   a  is to encode signals to received on the buses  202   a,    204   a,    206   a,  to be sent to the dock  216   a,  and to decode signals received from the dock to be sent to various subsystems and devices (not shown) of the notebook  200  via the buses  202   a,    204   a,    206   a,  in a conventional fashion. Similarly, the function of the logic interface  226   a  is to encode signals to received on the buses  218   a,    220   a,  and  222   a,  to be sent to the notebook  200   a,  and to decode signals received from the notebook via the docking connectors  208   a,    224   a,  to be sent to various subsystems and devices (not shown) of the dock  216   a  via the buses  218   a,    220   a,    222   a,  in a conventional fashion.  
         [0020]    In general, as previously indicated, the function of the each of the logic interfaces in each notebook and dock device is to encode signals transmitted by the device and decode signals received from the other device; to communicate the status of the device (e.g., docking status, the level of functionality of the connected devices); and to coordinate coherent transfer of signals between the devices.  
         [0021]    [0021]FIGS. 2B and 2C respectively illustrate notebook/dock combinations that are similar to the combination illustrated in FIG. 2A, except that they each include a different combination of bus bandwidth levels. In addition, the identity of the logic interface thereof is different. In particular, FIG. 2B illustrates a notebook  200   b  including a plurality of buses encompassing two “bandwidth levels”. In particular, the notebook  200   b  includes one or more medium bandwidth level buses, represented by a bus  204   b,  and one or more low bandwidth level buses, represented by a bus  206   b.  Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems of the notebook  200   b,  collectively designated by a reference numeral  207   b,  in a conventional fashion. The buses  204   b,  and  206   b,  are connected to a docking connector  208   b  of the notebook  200   b  via a logic interface  210   b.    
         [0022]    The docking connector  208   b  is designed to mate with a complementary docking connector  214   b  disposed on a dock  216   b.  The dock  216   b  includes one or more medium bandwidth level buses, represented by a bus  220   b,  and one or more low bandwidth level buses, represented by a bus  222   b.  Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems connected to and disposed on and within the dock  216   b,  collectively designated by a reference numeral  223   b,  in a conventional fashion. The buses  220   b,  and  222   b,  are connected to the docking connector  244   b  of the dock  216   b  via a logic interface  226   b.    
         [0023]    [0023]FIG. 2C illustrates a notebook  200   c  including a plurality of buses encompassing one bandwidth level. In particular, the notebook  200   c  includes one or more low bandwidth level buses, represented by a bus  206   c.  Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems of the notebook  200   c,  collectively designated by a reference numeral  207   c,  in a conventional fashion. The buses  206   c,  are connected to a docking connector  208   c  of the notebook  200   c  via a logic interface  210   c.    
         [0024]    The docking connector  208   c  is designed to mate with a complementary docking connector  214   c  disposed on a dock  216   c.  The dock  216   c  includes one or more low bandwidth level buses, represented by a bus  222   c.  Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems connected to and disposed on and within the dock  216   c,  collectively designated by a reference numeral  223   c,  in a conventional fashion. The buses  222   c,  are connected to the docking connector  214   c  of the dock  216   c  via a logic interface  226   c.    
         [0025]    In accordance with features of the embodiments described herein, a primary feature and function of the logic interfaces  210   a,    210   b,    210   c,    226   a,    226   b,    226   c,  is that they enable any of the notebooks  200   a,    200   b,    200   c,  to be docked to any of the docks  216   a,    216   b,    216   c,  and function properly, as the logic interfaces are capable of handling signals that are not useable by the respective device, potentially, of generating necessary signals that may not be present from signals that are present.  
         [0026]    [0026]FIGS. 2D and 2E are block diagrams illustrating the high-end notebook  200   a  coupled to the low-end dock  216   c  and the low-end notebook  200   c  coupled to the high-end dock  216   a,  respectively. As previously indicated, the logic interfaces  210   a,    210   c,    226   a,    226   c,  on the respective notebook and dock enable the respective device to identify which carrier bandwidths are supported on both sides of the docking connector and settle on the greatest common denominator.  
         [0027]    In addition, the embodiments illustrated are intended to be illustrative, not all-inclusive, as it is anticipated that there will be cases in which it would be beneficial to provide combinations of bandwidth levels other than those shown (e.g., high and low with no medium; high and medium with no low) in notebooks and docks. Still further, the definitions of what constitutes “high,” “medium,” and “low” bandwidth levels is meant to be illustrative and it is anticipated that these definitions will change, perhaps rapidly, as notebook and dock products evolve over time. It is also anticipated that there may be more than three such divisions of bandwidth levels.  
         [0028]    Taking all of the foregoing into account, the basic premise of the embodiments described herein is that, regardless of the number of how the bandwidth levels are defined and what combinations of bandwidth level buses are provided in the products, notebooks and docks designed in accordance with the described embodiments will be interchangeable.  
         [0029]    It will be recognized that, especially in the case of a high-performance notebook (e.g., the notebook  200   a ), the notebook will include functionality that will not be useful unless the notebook is docked to a dock that can implement that functionality. It will be further recognized that implementation of functionality that is not used results in unnecessary increase in power consumption and temperature of the notebook, further resulting in unnecessary strain on notebook resources and capacity. Therefore, in accordance with features of the embodiments described herein, a primary function of the logic interface on the notebook side is to detect which buses are present and enable functionality and switching based on the detected environment (e.g., connectivity).  
         [0030]    For example, FIG. 3 illustrates a notebook  300  and a dock  302  interconnected via docking connectors  303   a,    303   b  and embodying an AGP link implementation of one embodiment. As shown in FIG. 3, the notebook  300  includes a CPU  304 , connected to a memory control hub (“MCH”), or “North Bridge”,  306  in a conventional fashion. The MCH  306  is connected to a video subsystem  308  including an AGP controller  309  via an AGP bus  310 , defined herein as a “high bandwidth” bus. The MCH  306  is further connected to an “ICH”, or “South Bridge,”  310  in a conventional fashion. The South Bridge  310  is connected via a PCI bus  312 , defined herein as a “medium bandwidth” bus, to one or more PCMCIA expansion slots  314  for receiving expansion cards (not shown). The AGP controller  309  is connected to a logic interface  316  of the notebook  300  via a high speed serial interface  318 , which in a preferred embodiment is integrated into the logic interface  316 . Similarly, the PCI bus  312  is connected to the logic interface  316  via a Q-switch  318   a,  which in a preferred embodiment is integrated into the logic interface  316 . Two “low bandwidth” buses, including a USB bus  318   b  and an LPC bus  318   c  are also provided in the notebook  300  and connected to the logic interface  300 .  
         [0031]    On the dock  302  side, a logic interface  319  is connected via an AGP bus  320  to an AGP 4× expansion slot  322  via a high-speed serial interface  324  integrated into the logic interface  319 . Similarly, the logic interface  319  is connected via a PCI bus  326  to a SCSI controller  328  via a PCI-to-PCI bridge  330  integrated into the logic interface  319 . Still further, the logic interface is connected via a USB bus  332  to a hub  334  and via an LPC bus  336  to a serial I/O controller  338 .  
         [0032]    In a preferred embodiment, the logic interface  316  is capable of detecting whether or not the notebook  300  is docked to an AGP-capable dock (i.e., a dock in the “Desktop Replacement Docking” functional grouping), such as the dock  302 . If so, an AGP enable signal from the interface  316  switches the high speed serial interface  318  into the circuit; e.g., by closing a switch  324 ; otherwise, the AGP enable signal switches the high speed serial interface  318  out of the circuit; e.g., by opening the switch  324 . In this manner, when the high speed serial interface  318 , which consumes a great deal of power and generates a great deal of heat, is not needed (i.e., when the notebook  300  is not docked or is docked to a non-AGP-capable dock), it is switched off; otherwise, it is switched on.  
         [0033]    As can be seen, the principal advantage of the embodiments is that it enables multiple notebooks to be docked to multiple docks and function properly. Another advantage is that the environment of the notebook can be determined and automatically accounted for, in terms of reduction in power consumption and thermal production, thereby reducing unnecessary stress on notebook resources.  
         [0034]    Although illustrative embodiments have been shown and described, a wide range of modification, change and substitution is contemplated in the foregoing disclosure and in some instances, some features of the embodiment may be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the embodiments disclosed herein.