Scalable docking architecture to support various bandwidth

[0002] The disclosures herein relate generally to portable computers and, more particularly, to a scalable architecture for portable computer docking stations.

[0003] USB docking device class integrated circuit (“IC”) logic, as fully described in detail in related U.S. patent application Ser. No. 09/672,132 entitled “USB DOCKING DEVICE CLASS IC”, filed Sep. 27, 2000, and hereby incorporated by reference in its entirety, 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.

[0004] 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.

[0005] 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.

[0006] 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.

[0007] 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.

[0008] 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.

[0009] 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.

[0010] 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.

[0011] FIG. 1A is a table illustrating examples of potential notebook/dock groupings and bandwidth levels.

[0012] FIG. 1B is a block diagram of a potential implementation using the groupings illustrated in the table of FIG. 1A.

[0013] FIGS. 2A-2E are system block diagrams of notebook/dock combinations embodying features of one embodiment.

[0014] FIG. 3 is a system block diagram of a notebook/dock combination embodying a power-saving feature of one embodiment.

[0015] 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.

[0016] 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).

[0017] FIG. 1B illustrates a potential implementation of the definitions set forth in FIG. 1A. FIG. 1B illustrates three notebooks 100a, 100b, 100c, having different performance levels. Specifically, the notebook 100ais a high performance, or “high-end”, system; the notebook 100bis a mid-level performance, or “mainstream”, system; the notebook 100cis a basic, or “low-end”, system. Applying the functional groupings set forth in FIG. 1A, the notebooks 100a, 100b, and 100c, 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 102aconsisting of a full dock with an AGP 8× slot and a low-end dock 102bconsisting 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 100a, 100b, 100c, could be docked to the low-end dock 102b. Additionally, the notebook 100ccould be advantageously docked to the high-end dock 102a. If, for example, the low-end notebook 100cwere connected to the high-end dock 102a, the features of the docking station that are supported by the notebook would work; other features of the docking station would not work.

[0018] FIGS. 2A, 2B, and 2C are block diagrams representing various configurations of notebooks and docking stations according to one embodiment. Referring to FIG. 2A, a notebook 200aincludes a plurality of buses encompassing three “bandwidth levels”, as defined with reference to FIG. 1A. In particular, the notebook 200aincludes one or more high bandwidth level buses, represented by a bus 202a, one or more medium bandwidth level buses, represented by a bus 204a, and one or more low bandwidth level buses, represented by a bus 206a. Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems of the notebook 200a, collectively designated by a reference numeral 207a, in a conventional fashion. The buses 202a, 204a, and 206a, are connected to a docking connector 208aof the notebook 200avia a logic interface 210a, the function of which will be described in detail below.

[0019] The docking connector 208ais designed to mate with a complementary docking connector 214adisposed on a dock 216a. The dock 216aincludes one or more high bandwidth level buses, represented by a bus 218a, one or more medium bandwidth level buses, represented by a bus 220a, and one or more low bandwidth level buses, represented by a bus 222a. 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 216a, collectively designated by a reference numeral 223a, in a conventional fashion. The buses 218a, 220a, and 222a, are connected to the docking connector 214aof the dock 216avia a logic interface 226a, the function of which will be described in detail below.

[0020] In general, the function of the logic interface 210ais to encode signals received on the buses 202a, 204a, 206a, to be sent to the dock 216a, 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 202a, 204a, 206a, in a conventional fashion. Similarly, the function of the logic interface 226ais to encode signals received on the buses 218a, 220a, and 222a, to be sent to the notebook 200a, and to decode signals received from the notebook via the docking connectors 208a, 224a, to be sent to various subsystems and devices (not shown) of the dock 216avia the buses 218a, 220a, 222a, in a conventional fashion.

[0021] 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.

[0022] 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 200bincluding a plurality of buses encompassing two “bandwidth levels”. In particular, the notebook 200bincludes one or more medium bandwidth level buses, represented by a bus 204b, and one or more low bandwidth level buses, represented by a bus 206b. Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems of the notebook 200b, collectively designated by a reference numeral 207b, in a conventional fashion. The buses 204b, and 206b, are connected to a docking connector 208bof the notebook 200bvia a logic interface 210b.

[0023] The docking connector 208bis designed to mate with a complementary docking connector 214bdisposed on a dock 216b. The dock 216bincludes one or more medium bandwidth level buses, represented by a bus 220b, and one or more low bandwidth level buses, represented by a bus 222b. 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 216b, collectively designated by a reference numeral 223b, in a conventional fashion. The buses 220b, and 222b, are connected to the docking connector 244bof the dock 216bvia a logic interface 226b.

[0024] FIG. 2C illustrates a notebook 200cincluding a plurality of buses encompassing one bandwidth level. In particular, the notebook 200cincludes one or more low bandwidth level buses, represented by a bus 206c. Although not shown in detail, it will be recognized that the buses enable communication with various devices and subsystems of the notebook 200c, collectively designated by a reference numeral 207c, in a conventional fashion. The buses 206c, are connected to a docking connector 208cof the notebook 200cvia a logic interface 210c.

[0025] The docking connector 208cis designed to mate with a complementary docking connector 214cdisposed on a dock 216c. The dock 216cincludes one or more low bandwidth level buses, represented by a bus 222c. 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 216c, collectively designated by a reference numeral 223c, in a conventional fashion. The buses 222c, are connected to the docking connector 214cof the dock 216cvia a logic interface 226c.

[0026] In accordance with features of the embodiments described herein, a primary feature and function of the logic interfaces 210a, 210b, 210c, 226a, 226b, 226c, is that they enable any of the notebooks 200a, 200b, 200c, to be docked to any of the docks 216a, 216b, 216c, and function properly, as the logic interfaces are capable of handling signals that are not useable by the respective devices and, potentially generating necessary signals that may not be present from signals that are present.

[0027] FIGS. 2D and 2E are block diagrams illustrating the high-end notebook 200acoupled to the low-end dock 216cand the low-end notebook 200ccoupled to the high-end dock 216a, respectively. As previously indicated, the logic interfaces 210a, 210c, 226a, 226c, 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.

[0028] 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.

[0029] 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.

[0030] It will be recognized that, especially in the case of a high-performance notebook (e.g., the notebook 200a), 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).

[0031] For example, FIG. 3 illustrates a notebook 300 and a dock 302 interconnected via docking connectors 303a, 303band 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 318a, which in a preferred embodiment is integrated into the logic interface 316. Two “low bandwidth” buses, including a USB bus 318band an LPC bus 318care also provided in the notebook 300 and connected to the logic interface 300.

[0032] 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.

[0033] 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.

[0034] As can be seen, the principal advantage of the embodiments is that they enable 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.

[0035] 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.