Select mode signal transfer between serially linked devices

Abstract

In the example described, circuit (500) is adapted to receive an input signal at a local port (562) or a first system port (582). A transceiver (522) is configured to enter a first mode in response to a local wake-up signal and to transmit a system wake-up signal at a second system port (592) in response to the local wake-up signal. A controller (524) is configured to generate a local wake-up signal in response to an energy detection signal. An energy detector (526) is coupled to the first system port (582) and the local port (562) and is configured in a second mode to generate an energy detection signal in response to the detection of the energy of one of the first system input signals and local input signals received by the transceiver (522).

Description

Technical Field

[0001] In some electronic systems, various components are coupled by a physical layer including connectors and electrical wiring. In some applications, the limitations on the functionality of the various components can be limited by the cost, size, and number of the connectors, and / or the cost, size, and number of the individual wirings in the electrical wiring.

Summary of the Invention

[0002] In the example described, the circuit is adapted to receive an input signal at a local port or a first system port. The transceiver is configured to enter a first mode in response to a local wake-up signal and to transmit a system wake-up signal at a second system port in response to the local wake-up signal. The controller is configured to generate a local wake-up signal in response to an energy detection signal. The energy detector is coupled to the first system port and the local port and is configured to generate an energy detection signal in response to the detection of the energy of one of the first system input signal and the local input signal received by the transceiver in a second mode. 9

Brief Description of the Drawings

[0003] [Figure 1] It is a system diagram showing an exemplary vehicle including an exemplary system adapted to selectively transfer transmissions between serially chained devices of the exemplary system.

[0004] [Figure 2] It is a diagram of an exemplary transmission in an exemplary system adapted to selectively transfer transmissions between serially chained devices.

[0005] [Figure 3]A block diagram of an exemplary multistream generator adapted to aggregate input streams in an exemplary system adapted to selectively forward transmissions between serially chained devices is shown.

[0006] [Figure 4] This is a block diagram of an exemplary system including at least one stream disaggregator adapted to selectively forward transmissions between serially chained devices.

[0007] [Figure 5] This is a block diagram of an exemplary system including at least one bus unit adapted to generate and transfer system wake-up signals between series-chained bus units.

[0008] [Figure 6] Figure 5 is a flowchart illustrating an example method for issuing a wake-up signal for the system shown in the example.

[0009] [Figure 7] Figure 5 is a flowchart illustrating the example method for wake-up signal detection and wake-up signal processing in the example system.

[0010] [Figure 8] This is a block diagram of the first example wake-up signal processing scenario in the example system.

[0011] [Figure 9] This is a block diagram of the second example wake-up signal processing scenario in the example system.

[0012] [Figure 10] This is a block diagram of the third example wake-up signal processing scenario in the example system.

[0013] [Figure 11]This is a block diagram of another exemplary system including at least one stream disaggregator adapted to selectively forward transmissions between serially chained devices. [Modes for carrying out the invention]

[0014] In the diagram, similar reference numbers indicate similar elements, and various features are not necessarily depicted to a consistent scale.

[0015] Various electronic systems combine to form a system using interconnected components. As the functionality of the system increases, the complexity of the interconnections also increases. As more functionality is added to the system (for example, in response to increased integration and processing power), the number of terminals on the connectors increases, resulting in increased connector size, complexity, and / or cost.

[0016] Several electronic systems may be installed on a transport platform (such as an aircraft or automobile). Constraints in the structure of the mobile platform (e.g., due to human factors, safety considerations, and aerodynamic characteristics) may limit the space available for connectors and cabling of the electronic systems. Furthermore, access to connectors and cabling (e.g., for testing, replacement, and / or repair) may be restricted, for example, when the electronic system is installed on the vehicle's dashboard (which may include at least one airbag) (this increases operational costs).

[0017] An example of an electronic system that may be installed on a mobile platform is an automotive "infotainment" system, in which video data may be generated (or transmitted) by a control unit (e.g., a head unit or other data source). The generated video data may be transmitted to multiple display panels (e.g., a head-up display, an instrument cluster, and a central instrument display). Various cables / connectors are placed between the control unit and each of the different displays to send different types of display data from the control unit to different displays. A cable adapted to carry signals between two units (e.g., a display and a control unit) has a first connector (e.g., a first set of connectors) adapted to connect to a first mating connector of a first unit, a second connector (e.g., a second set of connectors) adapted to connect to a second mating connector of a second unit, and a cable harness (e.g., a flexible cable harness) having insulated wiring arranged to electrically couple signals (e.g., unidirectional and / or bidirectional signals) between the first and second connectors.

[0018] In one example, a plurality of displays may be connected to a control unit in a pair - multiple configuration, and in this case, the connection cables converge at one location (e.g., on the surface of the control unit) on the control unit. For example, a master control unit may include a pair of connectors and cables for communicating with each slave device of the system (e.g., in a star network topology). The convergence of connectors and cables in the control unit causes mechanical spacing problems, and the convergence of multiple connectors located side - by - side occupies significant space in an automobile. Also, video information (such as at least one video stream) from the control unit is high - resolution data that is continuously streamed to each display via its respective connector / cable pair. For point - to - point connections in a star topology, each video stream need not be associated with or identified by a networking address. Conventionally, video data from a head unit transmitted to a display is high - resolution data that is continuously streamed and is not in a form that can be easily networked as in some other data networking applications.

[0019] As described herein, an exemplary system is adapted to selectively transfer transmissions between serially - chained devices of the exemplary system. For example, the exemplary system may include a control unit coupled to a serial chain (e.g., at one end of the serial chain) of display units. An exemplary multi - stream generator may be coupled to the output of the control unit, and as a result, the exemplary multi - stream generator may encode (e.g., encapsulate) video data from multiple streams into a format adaptable to various types of displays in a serial chain (e.g., daisy - chain type displays). The problem of dense mechanical spacing due to cable / connector convergence at the control unit location can be alleviated by arranging the exemplary system components as shown in FIG. 1.

[0020] Figure 1 is a system diagram showing an exemplary vehicle including an exemplary system adapted to selectively forward transmissions between serial-chained devices of the exemplary system. Generally, system 100 is an exemplary system including a host vehicle 110. An exemplary multi-display system 120 may be installed in the host vehicle 110. The exemplary multi-display system 120 may include any number of displays in a serial chain, one end of which may be connected to a control unit.

[0021] The exemplary multi-display system 120 may include a control unit (e.g., a head unit 122), a first display (e.g., an instrument cluster display CLUSTER 124), a second display (e.g., a head-up display HUD 126), and a third display (e.g., a central instrument display CID 128). The exemplary multi-display system may include one or more head units 122. The head units 122 are adapted to receive sensor data (e.g., from cameras or instrument sensors) and generate video streams in response to the sensor data. Each head unit 122 transmits at least one generated video stream, each of which is received by a multi-stream generator 123. However, the use of multiple head units complicates the system, creates additional failure nodes, increases costs, and, for example, occupies more space in a limited area.

[0022] The multi-stream generator 123 (MG) may include an input (e.g., video input) coupled to the head unit 122 (e.g., may be included in the head unit 122), and may include an output coupled to the input of the stream disaggregator 125 (e.g., via cable 133). In one example, the multi-stream generator 123 may receive video streams from each head unit 122. In some examples, the multi-stream generator 123 may receive video streams from at least one head unit 122 (e.g., as a result, one or more video streams may be generated by the head unit 122 for stream aggregation by the multi-stream generator 123).

[0023] The stream disaggregator 125 may have a first output (e.g., local output) coupled to the display CLUSTER 124 (e.g., may be included), and may have a second output (e.g., system output) coupled to the input of the stream disaggregator 127 (e.g., via cable 135).

[0024] The stream disaggregator 127 may include a first output (e.g., local output) coupled to the display HUD 126 (e.g., may be included), and may include a second output (e.g., system output) coupled to the input of the stream disaggregator 129 (e.g., via cable 137).

[0025] The stream disaggregator 129 (SD) may have a first output (e.g., a local output) which is coupled to (e.g., may include) the display CD 128, and a second output (e.g., a system output) which is optionally coupled to the input of an optional stream disaggregator for display (not shown) (e.g., via another cable not shown). Other stream disaggregators may be sequentially coupled to the tail of the series chain connecting the series-chained displays (e.g., the tail of the series chain is on the opposite side of the end of the series chain connected to the head unit 122) (an illustrative wiring network is described hereafter in relation to Figure 4).

[0026] Compared to a star topology display system for three displays (which includes three cables and their respective connectors converging at a certain location on the control unit), the series-chain display system described herein reduces space and mechanical constraints (for example, the constraint is reduced to the space of a single connector / cable connected at the head unit 122).

[0027] The multistream generator 123 is configured to encode high-resolution real-time video data (including video-related data) into a packet format. The operation of the multistream generator will be described below in reference to Figure 3. The multistream generator 123 may be configured as a serializer (for example, it may be adapted to output video data serially, and the video data may be received asynchronously by the multistream generator 123 in serial or parallel format), and / or it may be configured to output video data in parallel. Each packet may contain an identifier (e.g., a stream identifier) ​​for identifying a particular encoded video stream and / or for identifying the destination of the packet (e.g., identifying the display to which the packet is addressed). The identifier may be parsed by a stream disaggregator according to the mode associated with each stream disaggregator (e.g., default or programmed configuration). Each packet is received by at least one stream disaggregator for forwarding (and / or decoding / deserializing).

[0028] Stream disaggregators (e.g., 133, 135, and 137) receive packets (e.g., having identifiers to indicate a destination display) and are configured to select between a first stream disaggregator output (e.g., a local output for combining information into locally coupled displays) and a second stream disaggregator output (e.g., a system output for forwarding information to at least one other stream disaggregator).

[0029] Figure 2 shows an exemplary transmission in an exemplary system adapted to selectively forward transmissions between serially linked devices. Generally, transmission 200 is an exemplary transmission distributed in packet format. The exemplary transmission may include streaming data for streaming video. The streaming video data may include (e.g., synchronized) audio data coupled to the streaming video. The streaming data may include content for displaying video and / or still images.

[0030] In the first example packet (e.g., packet 210), packet 210 includes a control (CTL) field 211, a payload (e.g., STREAM_PAYLOAD) field 212, an error correction code (ECC) field 213, a stream / destination (STRM) field 214, a reserved field 215, and a continuation (CONT) field 216.

[0031] Field 211 may indicate whether the stream payload (e.g., field 212) contains command data or streaming data. Command data contained in field 212 may include, for example, a start command for initiating playback of a selected video stream; a configuration command for, for example, configuring a mode and for a particular stream disaggregator to select a specific protocol (e.g., from various proprietary or industry standards) for communicating with a connected local display (e.g., a local display directed and cabled) and setting a playback channel for a particular display (e.g., for playing at least one selected stream containing a selected STRM field 214 value); a routing command, which is a command for selecting at least one stream to be routed to a local display (e.g., of a particular stream disaggregator); and / or a transfer command for selecting at least one stream to be transferred to another stream disaggregator (resulting in the first disaggregator transferring the selected stream to a second disaggregator and head unit downstream from the first stream disaggregator). In one example, configuration data may be pre-programmed into a specific stream disaggregator (for example, during system integration in an automobile factory, etc.) (e.g., resulting in reduced configuration time), and command data may be used to reprogram a given configuration during operation (e.g., the given configuration may be pre-programmed or programmed during operation).

[0032] The streaming data contained in field 212 may include video (e.g., still or dynamic video) information, audio information, or a combination thereof. The resolution of the streaming data may be selected to provide video (and / or sound) quality equivalent to that of a particular display and / or target functionality. The streamed video data may include pixel information. An example pixel may include 8 bits of red information, 8 bits of green information, and 8 bits of blue information. The number of rows and columns of pixels may be selected to produce video frames corresponding to the capabilities of a particular display screen. The video frames may be encoded as transmission symbols and / or as compressed information for transmission by the target display and subsequent decoding. The video frames may be streamed (e.g., transmitted as a time sequence of video frames associated with a particular video "feed").

[0033] Field 213 contains an ECC code (for example, for error detection and correction). The number of bits in field 213 can be increased (for example, from one parity bit to many more bits) to provide a higher level of error detection and even correction that may occur in packets 210 being transmitted and received. A receiver may evaluate the ECC code of a received packet against the other bits of the received packet to, for example, correct a corrupted packet and / or request retransmission of the original packet (for example, the original packet data) (for example, by sending it upstream). The length of the ECC field may be chosen to provide a performance level for a particular functionality (for example, for a dashboard display compared to a less critical infotainment display unit for rear-seat passengers).

[0034] Field 214 contains information that helps identify the display to which the received packet is routed. The number of bits in field 214 is sufficient to uniquely identify a particular stream (e.g., a video channel) and / or display (e.g., at least one display for consuming and playing the stream associated with the received packet). In the first example, field 214 contains enough bits to identify a particular stream (e.g., a channel number), and the stream disaggregator is programmed (e.g., via a configuration command as described herein) to route the received packet to at least one display (e.g., this is set to a channel number, and as a result, one or more displays may play the same stream). In the second example, field 214 contains enough bits to identify a particular display (e.g., an instrument panel or an electronic side-view "mirror" display) on which a particular received packet is displayed. In the third example, field 214 contains enough bits to indicate a code for selecting a predefined routing configuration for consuming (e.g., routing to a local display) and / or forwarding a particular received packet. In the fourth example, field 214 includes enough bits to include combinations of the functionalities described herein (e.g., some or all combinations) for the first, second, and third examples.

[0035] Field 215 is reserved for data transport for undefined purposes (e.g., unpublished or not yet published). For example, the reserved field may not necessarily transport useful data in early systems, but may be used to transport useful information in later systems, thus eliminating the need to change the packet length to make room for transporting information implemented later. Field 215 may contain enough bits to extend the transmission and reception of packets with a common packet length (e.g., according to a subsequent protocol standard associated with at least one existing FPD standard, or according to a proprietary protocol developed later).

[0036] Field 216 indicates whether the packet is the last packet in the stream. In an example where field 216 indicates that the packet is the last packet in the stream, the display consuming the packet may take action in response to the indication that a particular received packet is the last packet in the stream. The example action (for example, taken in response to the indication that a particular received packet is the last packet in the stream) could be a hypothetical action (for example, a quickly reversible action) such as dimming the display selected to show the stream related to the particular received packet. Packet transmission and forwarding will be described thereafter with reference to Figure 4.

[0037] In the second example packet (packet 220, etc.), packet 220 includes a control (CTL) field 221, a stop (e.g., STREAM_STOP) field 222, an error correction code (ECC) field 223, a stream / destination (STRM) field 224, and a reserved field 225.

[0038] Field 221 may indicate whether the stream payload contains command data (such as a stop command in field 222). The command data contained in field 222 may include a stop command. In response to a transmitted stop command, the downstream stream disaggregator and display identified by field 224 may power down, reinitialize, and / or reallocate previously allocated resources to display the stream associated with the received packet (e.g., the packet containing the stop command). In one example, field 222 may contain a command to terminate the operation of programmable hardware adapted to display video information (e.g., a code in stop field 222 may indicate that the instant packet is the last packet in the video stream indicated by field 224).

[0039] Field 223 contains ECC codes (for example, for error detection and correction), such as the codes included in Field 213.

[0040] Field 224 is similar to field 214 and may contain information indicating which stream is associated with the packet and / or information indicating the display to which the packet should be sent.

[0041] Field 225 is similar to field 215. The presence of a stop field can be used to determine that a packet containing a stop field is the last packet in a stream; therefore, continuation fields such as field 216 do not need to be implemented in packets containing a stop field. By using a stop field to indicate that the stream should end, the space used by continuation fields in packets with a stop field is freed up and reserved for potential future use (e.g., future use for any purpose).

[0042] Figure 3 is a block diagram of an exemplary multistream generator adapted to aggregate input streams in an exemplary system adapted to selectively forward transmissions between serially linked devices. The multistream generator 300 is an exemplary multistream generator that may be located on board 302. The multistream generator 302 includes an input (e.g., receiver 310) adapted to receive at least one video stream from a selected head unit, and an output (e.g., transmitter 390) adapted to forward the packetized video stream to a first stream disaggregator. The packetized video stream may be generated (e.g., sourced) by a video source (e.g., a digital camera) according to the MIPI (Mobile Industry Peripheral Interface) Camera Serial Interface (CSI). The video source for generating the exemplary video 0 to video 7 streams may include a sensor (e.g., sensor 402), the sensor may include various cameras such as backup or side-view cameras, each camera may be configured to generate its own video stream. The video source for generating the example video 0 to video 7 streams may also include the head unit itself (e.g., head unit 401) and may generate at least one video stream for display in response to sensors such as sensor 402 (as described later in relation to Figure 4).

[0043] In one example, the clock generator 304 is located on the board 302 and is adapted to generate clock signals such as the video pixel clock (VP clock), video link layer clock (vclk_link), frame clock (clk_frame), and lane clock (clk_div40). In some examples, some of the clock signals may be generated by circuit elements not included on the board 302. The architecture of the multistream generator is also scalable (e.g., by powers of 2), and as a result, the multistream generator can aggregate a selected number (e.g., 8 or more) video streams (which can be addressed by including a sufficient number of bits in fields 214 and 224). In some examples, the receiver may include a transmitter, and as a result, information may be transmitted from the example receiver 310 (e.g., a second, opposite direction). The multistream generator 300 may be adapted to transmit data bidirectionally (e.g., 165 megabits per second upstream and 13 gigabits per second downstream). An example of bidirectional transmission / reception of transmitted data is described in U.S. Patent No. US9,363,067, issued June 7, 2016, “Data Signal Transceiver Circuit Element for Providing Simultaneous Bidirectional Communication Over a Common Conductor Pair,” which is incorporated herein by reference. [Patent Document 1] U.S. Patent No. US9,363,067

[0044] In the case of the first video stream (e.g., video In0) in the illustrated multistream generator 300, the pixel aligner 312 is adapted to sample the first video transmission and align (e.g., synchronize) the sampled data with the internal clock of the multistream generator 300 (e.g., the VP clock), and to generate horizontal synchronization (hsync) and vertical synchronization (vsync) information (e.g., for identifying the pixel position of the received pixel data). The sampled data is verified by checking (and correcting, if possible) errors using a 32-bit cyclic redundancy checker (CRC) 314. The verified information is stored in the video buffer 322 and temporarily associated with the hsync and vsync information. For example, start and stop packets may be associated with the start and end of the displayed video frame, respectively. The video stream may be received as a serial or parallel stream (e.g., from the head unit), accessed from system memory (e.g., frame memory), and / or transmitted / accessed by a combination thereof.

[0045] The stream mapper 330 is adapted to receive stream information (e.g., the video In0 stream) and associated hsync and vsync signals from the video buffer 322. In response to the video buffer 322 information and associated hsync and vsync signals, the stream mapper 330 is configured to associate a particular video stream with a particular display (e.g., by setting the value of an STRM field such as field 214 or field 224).

[0046] The lane-0 link layer 332 is configured to generate signals (e.g.) adapted to control physical layer parameters for transmitting data on lane-0, according to a system protocol (e.g., the FPD protocol described later). The lane-1 link layer 334 is configured to generate link control signals (e.g.) adapted to control physical layer parameters for transmitting data across lane-1, according to a system protocol. The link control signals may be generated in synchronization with (e.g., in response to) the video link layer clock.

[0047] Packets from a specific stream (e.g., the video In0 stream) may be transmitted via either lane-0 or lane-1 in response to an allocation made by the transmit distributor (TX distributor) 342. The TX distributor 342 can allocate at least one transmit lane so that pixels of a video frame can be transmitted at a rate sufficient to achieve the frame rate of the display indicated by the STRM field. A first output of the TX distributor 342 is coupled to transmit lane-0 data to the input of framer 352, and a second output of the TX distributor 342 is coupled to transmit lane-1 data to the input of framer 354. Pixels of a video frame may be transmitted in synchronization with the frame clock. In some examples, a specific lane may be associated with a respective display (e.g., as a system design choice), and as a result, video streams may be associated with (e.g., transmitted to) a respective display. In some cases, lanes can be dynamically allocated based on network traffic, so lanes can carry different video streams (for example, if a stream disaggregator associates incoming packets of a particular video stream with a specific display and adapts to forward / transmit packets of a given video stream to the correct display).

[0048] Framers 352 and 354 are adapted to generate transmit frames according to a system protocol such as the Low-Voltage Differential-Signaling (LVDS) protocol. The system protocol may be an LVDS standard such as the Platform Panel Display Link (FPD) protocol (e.g., FPD-Link I, FPD-Link II, FPD-Link III, and any subsequent standards related to at least one existing FPD standard). The system protocol may also include “sub-LVDS standards,” current-mode and / or voltage-mode driver / receiver, and other low-power high-speed signaling protocol (including Gigabit Multimedia Serial Link GMSL). The FPD framer 362 is adapted to match data for transmission within a transmit frame, the FPD encoder 372 is adapted to encode the matched data as symbols for transmission within a transmit frame, and the FPD frame physical alignment (FRAME PHY ALIGN) 382 is adapted to buffer the encoded symbols for synchronous transmission by transmitter 390 via lane-0 (e.g., clocked by a lane clock). The FPD framer 364 is adapted to match data for transmission within a transmit frame, the FPD encoder 374 is adapted to encode the matched data as symbols for transmission within a transmit frame, and the FPD frame physical alignment (FRAME PHY ALIGN) 384 is adapted to buffer the encoded symbols for synchronous transmission by transmitter 390 via lane-1. The encoded symbols can be decoded by a receiver such as receiver 422, for example, as described below, and can be encoded by a stream forwarder such as stream forwarder 426 (e.g., a stream transmitter).

[0049] In the case of the second video stream (e.g., video In7) in the illustrated multistream generator 300, the pixel aligner 316 samples the video transmission and adapts the sampled data to match the internal clock of the multistream generator 300 to generate horizontal synchronization (hsync) and vertical synchronization (vsync) information. The sampled data is verified by checking for errors with a 32-bit cyclic redundancy checker (CRC) 318. The verified information is stored in the video buffer 324 and temporarily associated with the hsync and vsync information, so that, for example, start and stop packets may be associated with the beginning and end of the video frame to be displayed, respectively.

[0050] The stream mapper 330 is adapted to receive stream information (e.g., video In7 stream) and associated hsync and vsync signals from the video buffer 324. In response to the video buffer 324 information and associated hsync and vsync signals, the stream mapper 330 is configured to associate a particular video stream with a particular display (e.g., by setting the values ​​of STRM fields such as field 214 or field 224).

[0051] The lane-2 link layer 336 is configured to generate signals (for example) adapted to control physical layer parameters in order to transmit data over lane-2, according to the system protocol. The lane-3 link layer 338 is configured to generate signals (for example) adapted to control physical layer parameters in order to transmit data over lane-3, according to the system protocol.

[0052] Packets from a specific stream (e.g., the Video In7 stream) may be transmitted via either lane-2 or lane-3 in response to an allocation made by the transmit distributor (TX distributor) 344. The TX distributor 344 may allocate at least one transmit lane, so that pixels can be transmitted at a rate sufficient to achieve the frame rate of the display indicated by the STRM field. The first output of the TX distributor 344 is coupled to transmit lane-2 data to the input of framer 356, and the second output of the TX distributor 344 is coupled to transmit lane-1 data to the input of framer 358.

[0053] Framers 356 and 358 are adapted to generate transmit frames according to a system protocol such as the Low Voltage Differential Signaling (LVDS) protocol. The system protocol may be an LVDS standard such as the 4th revision of the Flat Panel Display (FPD) Link Protocol. The FPD framer 366 is adapted to match data for transmission within the transmit frame, the FPD encoder 376 is adapted to encode the matched data as symbols for transmission within the transmit frame, and the FPD frame physical matcher (FRAME PHY ALIGN) 386 is adapted to buffer the encoded symbols for synchronous transmission by the transmitter 390 over lane-2. The FPD framer 368 is adapted to align data for transmission within a transmit frame, the FPD encoder 378 is adapted to encode the aligned data as symbols for transmission within a transmit frame, and the FPD frame physical alignment (FRAME PHY ALIGN) 388 is adapted to buffer the encoded symbols for synchronous transmission by the transmitter 390 over lane-3.

[0054] Other video inputs (e.g., Video In2 to Video In6), lane outputs (e.g., Lane-4 to Lane-15), and circuit elements may be included, so the system bandwidth is sufficient to handle (e.g.) more displays (e.g., for instrument, side and rear view, navigation, and passenger infotainment systems) and / or higher resolutions. As will be described later in relation to Figure 4, the outputs (e.g., multi-stream outputs) are coupled to at least one stream disaggregator to couple the selected video streams to their respective local displays. Local displays do not need to be coupled to a stream disaggregator, but wiring local displays that are not coupled to a stream disaggregator increases the wiring requirements (e.g., the number of connectors, cables, and conductors) in systems with multiple displays and video streams.

[0055] Figure 4 is a block diagram of an exemplary system including at least one stream disaggregator adapted to selectively forward transmissions between serially linked devices. For example, system 400 is an exemplary system including a head unit 401, a multistream generator 410, a stream disaggregator 420 (e.g., locally coupled to local display 404 via cable 405), a stream disaggregator 430 (e.g., locally coupled to local display 406 via cable 407), and a stream disaggregator 440 (e.g., locally coupled to local display 408 via cable 409). Stream disaggregators 420, 430, and 440 can be adapted to transmit data bidirectionally (e.g., 165 megabits per second upstream or 13 gigabits per second downstream).

[0056] In one example, the head unit 401 is coupled to receive sensor information from the sensor 402. The sensor 402 may be a set of sensors related to the electronic systems of a vehicle (e.g., vehicle 110). Such sensors may include sensors adapted to detect driver control (e.g., gear shift, lights, steering wheel, turn signal lever, and other controls), vehicle attributes (e.g., speed, gas level temperature, fuel flow, tire pressure, seat belts, and other attributes), and positioning (e.g., radar, satellite navigation, cameras, lane and curve sensors, and other related information). The head unit 401 is adapted to generate output information (e.g., video information) in response to the sensor information. Additional head units 401 may be coupled between various sensors 402 and the multistream generator 410.

[0057] The head unit 401 is adapted to generate video information for display on local displays 404 (e.g., this could be CLUSTER 124), 406 (e.g., this could be a head-up display HUD 126), and 408 (e.g., this could be a central instrument display CID 128). For example, the head unit may generate a first video stream of the vehicle dashboard in operation (e.g., for display on the display panel for the replacement of mechanical gauges), a second video stream for the HUD (e.g., for displaying navigation information on a virtual screen on the windshield), and a third video stream for the CID (e.g., for displaying real-time images from a rear-facing backup camera). The head unit 401 is adapted to output the video streams as individual bitstreams.

[0058] The multistream generator 410 is a multistream generator such as the multistream generator 300 described above. The multistream generator 410 is coupled to the video output of the head unit 401 (e.g., each of the video outputs) and is adapted using a system protocol to combine the independent video streams (e.g., at least two) of the video stream received from the head unit 401 into an integrated (e.g., multistream) video stream. The multistream generator is adapted to packetize the information from the integrated video stream (e.g., containing at least two video streams) and transmit the integrated video stream (multistream). Therefore, the multistream generator is deployed as the source node of the integrated video stream.

[0059] Each individual packet (generated by the multistream generator) includes an identification field, such as an STRM identifier, which can identify a selected display (e.g., an addressed display and / or an addressed node) as the packet's destination. The multistream generator 410 is adapted to combine the encoded packets into the source output of the multistream generator 410 (e.g., the source node). A first cable (411) is connected between the multistream generator 410 (e.g., the source node) and a first stream disaggregator (e.g., stream disaggregator 420). The first cable includes conductors (and associated insulators / shields) sufficient to carry information for all lanes (e.g., at least one lane) over which video information is transmitted.

[0060] The stream disaggregator 420 includes a local link controller 421, stream inputs (such as a receiver 422), a stream selector 423, a demultiplexer (DEMUX) 424, and a switch 427 (which includes a local exporter 425 and a stream forwarder 426). Receiver 422 may include a physical layer receiver, local exporter 425 may include a physical layer driver, and stream forwarder 426 may include a physical layer driver. Receiver 422 has a receiver output. Receiver 422 has a receiver input adapted to receive input data (e.g., an integrated video stream) from the output of a source node (e.g., a multistream generator 410). The input data may be (and / or may be) an incoming packet containing an identification field, which is transmitted by the source node. The input data may be received as serial or parallel data. The input data is received according to a system protocol (e.g., the FPD protocol) different from the local protocol (e.g., the eDP protocol described later).

[0061] The stream selector 423 includes a selector output. The stream selector 423 is coupled to a receiver output (e.g., of receiver 422), and the stream selector 423 is configured to generate a destination indicator at the selector output (e.g., of stream selector 423). For example, the stream selector 423 is adapted to monitor receiver 422 for received transmissions (e.g., packets 210 and 220) based on the contents of the STRM field (e.g., which may include functional data), and to program the demultiplexer (DEMUX) 424 in response. In one example, the stream selector 423 is adapted to generate a destination indicator in response to an identification field (the stream selector 423 is optionally adapted to receive an identification field).

[0062] Switch 427 includes a switch local output and a switch system output. Switch 427 is coupled to the output of receiver 422 (or optionally to the input of receiver 422) and is adapted to generate a transmission (e.g., an output signal) at the switch local output (e.g., a first output of the switch) in response to instructions from the stream selector 423 output and input data, and is adapted to generate a transmission at the switch system output in response to input data. The switch local output is adapted to be coupled to a first destination node, and the switch system output is adapted to be coupled to a second destination node. For example, switch 427 is adapted to generate an output packet adapted to be transmitted at the switch local output (e.g., local exporter 425) in response to an identification field, for example, when the identification field indicates that the packet should be exported to local display 404. In one example, switch 427 is adapted to route input data to a switch system output (e.g., stream forwarder 426) in response to a destination indication, for example, when the destination indication at the output of stream selector 423 indicates that the packet should be forwarded to another display (e.g., the packet should not be exported to local display 404). In another example, switch 427 forwards (e.g., transmits) all input data received by stream disaggregator 420, and the input data is combined from receiver input 422 (this combination may include combining the input data via receiver 422 itself and receiver 422 output), so that a transmit at the switch system output is generated by switch 427 in response to the input data (e.g., regardless of the contents of stream fields 214 and 224).

[0063] The demultiplexer 424 includes a first output adapted to be coupled to a first destination node, and the demultiplexer 424 includes a second output adapted to be coupled to a second destination node. For example, the demultiplexer 424 includes a first output adapted to be coupled to a local display 404 via a local exporter 425. The first destination node is a local node address (e.g., local to the case of stream disaggregator 420) that can be associated with at least one display node address. In this example, the demultiplexer 424 includes a second output adapted to be coupled to a local display 406 (e.g.) via a stream forwarder 426, cable 412, and stream disaggregator 430. The second destination node is a non-local node address that can be associated with a display node address that indicates a node address other than the node address associated with the first destination node. Node addresses can be the logical addresses of various display nodes, while stream field content identifies a specific video stream (e.g., it can be selectively received by one or more displays having different logical addresses). A stream selector can be dynamically programmed to direct the selected video stream (e.g., in response to an received control packet) to the local display associated with the stream selector. A stream forwarder 426 is coupled to the switch system output, and the stream forwarder is adapted to transmit according to the system protocol.

[0064] In one example, the demultiplexer 424 is adapted (e.g., by switching) to combine the incoming packet with the first output and the second output of the switch in response to the destination indication. In one example, the demultiplexer 424 is adapted to generate the packet at at least one of the selected first output and the second output of the switch in response to the identification field. In one example, the demultiplexer 424 is adapted to generate the packet destination indication in response to the identification field of the incoming packet.

[0065] The local link controller is a local controller coupled to the switch local output, which is adapted to transmit to the display. The local link controller 421 is adapted to monitor transmissions (e.g., packets 210 and 220) received by the receiver 422 with respect to commands (e.g., function data). The local link controller 421 is adapted to control the transmission of packets from the switch local output according to a local protocol (e.g., a protocol different from the system protocol).

[0066] The local exporter 425 is coupled to the first output of the demultiplexer 424, and the local exporter 425 includes an exporter output adapted for coupling to a display. For example, the first output of the demultiplexer 424 is coupled to the input of the local exporter 425. The exporter output of the local exporter 425 may be coupled (e.g., connected) to the local display 404.

[0067] The output of the local exporter 425 includes a local protocol. In one example, the local protocol is a DisplayPort protocol, such as the Video Electronics Association of America (VESA) embedded DisplayPort (eDP) standard. Thus, input data may be received by a receiver 422 that follows a system protocol (e.g., FDP) different from at least one local protocol. Other DisplayPort protocols that may be supported as local protocols include DisplayPort (DP), Open Liquid Crystal Display Interface (OpenLDI), Mobile Industry Processor Interface (MIPI) Display Serial Interface (DSI), and Camera Serial Interface (CSI). The first local protocol (e.g., 405) of a first display (e.g., 404) may be a different protocol from the second local protocol (e.g., 407) of a second display (e.g., 406).

[0068] The stream disaggregator 420 may be programmed to operate according to a protocol associated with a specific display locally coupled to the local exporter 425. For example, the multistream generator 410 may configure the stream disaggregator 420 by sending a start command to the local link controller 421 that includes instructions for the selected protocol. Instructions for the selected protocol may be included, for example, in the stream payload 212. In the exemplary system, the first stream disaggregator (e.g., 420) is adapted to select a first local protocol (e.g., 405), and the second stream disaggregator (e.g., 430) is adapted to select a second local protocol, which is a different protocol from the first local protocol.

[0069] In the exemplary system having two displays, a first cable (e.g., 411) is coupled between the output of a multistream generator 410 and the input of a first stream disaggregator 420, and a second cable (e.g., 412) is coupled between the second output of the first stream disaggregator 420 and the input of a second stream disaggregator 430. In the exemplary system having two displays, received packets (e.g., encoded packets) of the first video stream are transmitted to the first display via the first cable (e.g., via the first switch local output), and received packets (e.g., encoded packets) of the second video stream are transmitted to the second display via the first and second cables (e.g., via the first switch system output and the second switch local output).

[0070] In an example having at least two displays, the stream disaggregator 430 may include: a second receiver having a second receiver output and a second receiver input adapted to receive second input data from a first switch local output; a second selector having a second selector output, the second selector being coupled to the second receiver and configured to generate a second destination indication at the second selector output; and a second switch having a second switch local output and a second switch system output, the second switch being coupled to the second receiver and adapted to generate a transmission at the second switch local output in response to instructions for the second selector output and second input data, and adapted to generate a transmission at the second switch system output in response to second input data.

[0071] In an exemplary system having at least two displays, the stream disaggregator 430 further includes a second local controller coupled to a second switch-local output, the second switch-local output being adapted to transmit to a second display, and a second local exporter being configured to transmit data to the second display in response to a packet initiation command including a second destination indicator pointing to the second display.

[0072] In another exemplary system having at least two displays, a head unit is adapted to generate at least two video streams at the output of the head unit, and a multistream generator is adapted to be coupled to the output of the head unit and generate encoded packets containing information from at least two video streams, and to transmit the encoded packets to the source output, the input data containing packets from at least one of the two video streams. The encoded packets may be encoded by encoders such as FDP encoders 372, 374, 376, and 378, and the encoded packets may be decoded by a receiver (e.g., receiver 422 of a downstream stream disaggregator).

[0073] In an exemplary system having at least two displays, the system comprises: a head unit adapted to generate at least two video streams; a multistream generator coupled to the head unit, which generates encoded packets including an identification field and containing information from at least two video streams, and is adapted to combine the encoded packets to the output of the multistream generator; and a first stream disaggregator having a first stream input coupled to the output of the multistream generator, wherein the first stream disaggregator has a first output adapted to combine the received encoded packets to the first display in accordance with a first local protocol in response that the identification field of the received encoded packet indicates a node address of the first display, and the first stream disaggregator receives the encoded packet The system includes a first stream disaggregator having a second output adapted to forward an received encoded packet in response to the identification field of the received encoded packet indicating a node address other than a first display node, and a second stream disaggregator having a second stream coupled to the second output of the first stream disaggregator, wherein the second stream disaggregator has a first output adapted to combine the received encoded packet with a second display according to a second local protocol in response to the identification field of the received encoded packet indicating a second display node, and the second stream disaggregator has a second output adapted to forward the received encoded packet in response to the identification field of the received encoded packet indicating a node address other than a second display node address.The exemplary system further includes a third stream disaggregator having a third stream input coupled to a second output of a second stream disaggregator, the third stream disaggregator having a first output adapted to couple a received encoded packet to a third display in response that the identification field of the received encoded packet indicates a third display node address, and the third stream disaggregator having a second output adapted to forward a received encoded packet in response that the identification field of the received encoded packet indicates a node address other than the third display node address. The exemplary system may further include a first cable connecting the output of a multistream generator to a first stream input, and a second cable connecting the second output of a first stream disaggregator to a second stream disaggregator, wherein encoded packets of the first video stream are transmitted to a first display via the first cable, and encoded packets of the second video stream are transmitted to a second display via the first and second cables. In the exemplary system, the first local protocol may be a different protocol from the second local protocol.

[0074] An exemplary method for networking a multi-display system may include operations such as: sending a first transmission containing information about the received encoded packet to the first display in response to the identification field of the received encoded packet indicating the node address of the first display; forwarding a second transmission containing information about the received encoded packet in response to the identification field of the received encoded packet indicating a node address other than the first display node address; sending a third transmission containing information about the received encoded packet to the second display in response to the identification field of the received encoded packet indicating the second display; and forwarding a fourth transmission containing information about the received encoded packet in response to the identification field of the received encoded packet indicating a node address other than the second display node address. When the received encoded packet is a first encoded packet, the exemplary method may further include generating a first encoded packet in response to information received from a first video stream, generating a second encoded packet in response to information received from a second video stream, transmitting the first encoded packet of the first video stream to a first display via a first cable, and transmitting the second encoded packet of the second video stream to a second display via the first and second cables. The exemplary method may further include generating a first video stream in response to sensors in a vehicle including a first display and a second display.

[0075] In the exemplary system having three displays, a first cable (e.g., 411) is coupled between the output of a multistream generator 410 and the input of a first stream disaggregator 420; a second cable (e.g., 412) is coupled between the second output of the first stream disaggregator 420 and the input of a second stream disaggregator 430; and a third cable (e.g., 413) is coupled between the second output of the second stream disaggregator 430 and the input of a third stream disaggregator 440. In an exemplary system having three displays, the encoded packets received from a first video stream are transmitted to the first display via a first cable (e.g., via a first switch local output), the encoded packets received from a second video stream are transmitted to the second display via a first cable and a second cable (e.g., via a first switch system output and a second switch local output), and the encoded packets received from a third video stream are transmitted to the third display via a first cable, a second cable, and a third cable (e.g., via a first switch system output, a second switch system output, and a third switch local output).

[0076] As illustrated in the examples described herein, additional display and video streams may be added to a multiple display unit without increasing the number of cables coupled (e.g., physically coupled) to the head unit 401 and / or multistream generator 410.

[0077] Figure 5 is a block diagram of an exemplary system, which includes at least one bus unit adapted to generate and transmit a system wake-up signal between series-chained bus units. For example, system 500 is an exemplary system and includes a head unit 401 (e.g., coupled to a sensor 402), a first bus unit 510 (e.g., locally coupled to the head unit 401 via a local port 561 and cable 560), a second bus unit 520 (e.g., locally coupled to a touch display 572 via a local port 562 and cable 405), a third bus unit 530 (e.g., locally coupled to a touch display 573 via a local port 563 and cable 407), and a fourth bus unit 540 (e.g., locally coupled to a touch display 574 via a local port 564 and cable 409). Bus units 510, 520, 530, and 540 may be adapted to transmit data bidirectionally (for example, at 165 megabits per second upstream or 13 gigabits per second downstream). Bus units 520, 530, and 540 may be serializers and / or deserializers (e.g., SERDES) and / or disaggregators (420, 430, and 440, respectively).

[0078] In this specification, in the exemplary wake-up sequences generally described thereafter, the second bus unit 520 may be configured from a power-saving mode to an active mode (e.g., awakened) by a local wake-up signal generated in response to a wake-up event detected on the touch display 572. In response to the local wake-up signal, the second bus unit 520 may generate a system wake-up signal and transmit it to the first bus unit 510 (e.g., as a result, the system wake-up signal is transmitted upstream, and in response, the first bus unit 510 is woken). Similarly, the second bus unit 520 may generate a system wake-up signal and transmit it to the third bus unit 530 (e.g., as a result, the system wake-up signal is transmitted downstream, and in response, the third bus unit 5 is woken). In this example, the third bus unit 530 may, in response to receiving a system wake-up signal, generate a subsequent wake-up signal and transmit it to the fourth bus unit 540 (for example, the system wake-up signal is transmitted downstream, and in response, the third bus unit 530 is woken up). Other wake-up sequences are described below (for example, in relation to Figures 8, 9, and 10).

[0079] In the first exemplary system, system 500 includes a first bus unit (FBU) 510, which has a first system port (e.g., downstream D-port 591), an FBU local port (e.g., local L-port 561), an FBU wake-up input, an FBU transceiver 512, an FBU controller 514, and an FBU energy detector 516. The FBU transceiver 512 is coupled to the FBU first system port, the FBU local port, and the FBU wake-up input.

[0080] The first system port of the FBU (e.g., 591) is adapted to receive the first system input signal of the FBU. The FBU local port (e.g., 561) is adapted to receive the FBU local input signal. The FBU transceiver 512 is configured to transmit the data of the first system input signal of the FBU to the FBU local port (e.g., 561) in the first mode of the FBU (e.g., active mode). The FBU transceiver 512 is configured to conserve power in the second mode of the FBU. The FBU transceiver 512 is configured to enter the first mode of the FBU in response to the FBU local wake-up signal. The FBU transceiver 512 is configured to transmit the FBU system wake-up signal in response to the FBU local wake-up signal on the first system port of the FBU (e.g., 591) and one of the FBU local ports (e.g., 561).

[0081] The FBU controller 514 has an FBU energy detection input and an FBU wake-up output, the FBU wake-up output being coupled to the FBU wake-up input. The FBU controller 514 is configured to generate an FBU local wake-up signal at the FBU wake-up output in response to the FBU energy detection signal.

[0082] The FBU energy detector 516 has an FBU energy detection output coupled to an FBU energy detection input. The FBU energy detector 516 is coupled to a first FBU system port (e.g., via bus 551) and an FBU local port (e.g., via node 561a). The FBU energy detector 516 is configured to generate an FBU energy detection signal at the FBU energy detection output in response to FBU detection of the energy of either the first FBU system input signal (e.g., via node 561a) or the FBU local input signal received by the FBU transceiver 512 in a second FBU mode.

[0083] In the first exemplary system, system 500 further includes a second bus unit (SBU) SBU 520 having a first system port (e.g., upstream U-port 582). The SBU first system port is coupled to a first system port of an FBU (e.g., downstream D-port 591). The SBU first system port (e.g., 582) is adapted to receive an FBU system wake-up signal, and the FBU first system port (e.g., 591) is adapted to receive an SBU system wake-up signal (e.g., transmitted by SBU 520 via the SBU first system port).

[0084] SBU 520 may further include a second system port of the SBU (e.g., downstream D-port 592), a local port of the SBU (e.g., local L-port 562), an SBU wake-up input, an SBU transceiver 522, an SBU controller 524, and an SBU energy detector 526. The SBU transceiver 522 is coupled to the first system port of the SBU, the second system port of the SBU, the local port of the SBU, and the SBU wake-up input.

[0085] The SBU's first system port (e.g., 582) is adapted to receive the SBU's first system input signal, the SBU's second system port (e.g., 592) is adapted to receive the SBU's second system input signal, and the SBU's local port (e.g., 562) is adapted to receive the SBU's local input signal. The SBU transceiver 522 is configured to transmit data of the SBU's first system input signal to the SBU's second system port (e.g., 592) in the SBU's first mode (e.g., active mode), and to conserve power in the SBU's second mode (e.g., power saving mode). The SBU transceiver 522 is configured to enter the SBU's first mode in response to the SBU local wake-up signal. The SBU transceiver 522 is configured to transmit the SBU system wake-up signal on either the SBU's first system port or the SBU's second system port in response to the SBU local wake-up signal.

[0086] In general, SBU 520 can detect wake-up signals on any of the first system port (e.g., 582), the second SBU system port (e.g., 592), and the SBU local port (e.g., 562). SBU 520 is configured to generate a subsequent wake-up signal (in response to the detected wake-up signal) to be transmitted to the port that received the detected wake-up signal. In the first scenario, a wake-up signal is detected via the SBU local port (e.g., 562), and in response, SBU transceiver 522 transmits a system wake-up signal via the first SBU system port (e.g., 582) and the second SBU system port (e.g., 592). In the second scenario, a wake-up signal is detected via the SBU's first system port (e.g., 582), and in response, the SBU transceiver 522 transmits a system wake-up signal via the SBU's second system port (e.g., 592) and a local wake-up signal via the SBU's local port (e.g., 562). In the third scenario, a wake-up signal is detected via the SBU's second system port (e.g., 592), and in response, the SBU transceiver 522 transmits a system wake-up signal via the SBU's first system port (e.g., 582) and a local wake-up signal via the SBU's local port (e.g., 562). In response to the SBU 522 receiving a system wake-up signal from either the FBU 510 or the third bus unit 530, it may transmit a local wake-up signal to the touch display 572 to signal the touch display to switch from power-saving mode to active mode.

[0087] The SBU controller 524 has an SBU energy detection input and an SBU wake-up output, the SBU wake-up output being coupled to the SBU wake-up input. The SBU controller 524 is configured to generate an SBU local wake-up signal at the SBU wake-up output in response to the SBU energy detection signal.

[0088] The SBU energy detector 526 has an SBU energy detection output coupled to an SBU energy detection input. The SBU energy detector 526 is coupled to an SBU first system port (e.g., 582), an SBU second system port (e.g., 592), and an SBU local port (e.g., 562). In SBU second mode, the SBU energy detector 526 is configured to generate an SBU energy detection signal at the SBU energy detection output in response to an SBU detection of one of the energies of the SBU first system input signal (e.g., via node 582a), the SBU second system input signal (e.g., via bus 552), and the SBU local input signal (e.g., via node 562a), which are received by the SBU transceiver 522.

[0089] In the first exemplary system, system 500 further includes a third bus unit (TBU) 530, the TBU 530 having a first TBU system port (e.g., upstream U-port 583), an optional second TBU system port (e.g., downstream D-port 593), a TBU local port (e.g., local L-port 563), a TBU wake-up input, a TBU transceiver 532, a TBU controller 534, and a TBU energy detector 536. The first TBU system port (e.g., 583) is coupled to the second TBU system port (e.g., 592). The TBU transceiver 532 is coupled to the first TBU system port, an optional second TBU system port, a TBU local port, and a TBU wake-up input.

[0090] A first TBU system port (e.g., 583) is adapted to receive a first TBU system input signal, an optional second TBU system port (e.g., 593) may be adapted to receive a second TBU system input signal, and a TBU local port (e.g., 563) may be adapted to receive a local TBU input signal. The TBU transceiver 532 is configured to transmit data of the first TBU system input signal to either the local TBU port (e.g., 563) or the second TBU system port (e.g., 593) in a first TBU mode (e.g., active mode), and to conserve power in a second TBU mode (e.g., power saving mode). The TBU transceiver 532 is configured to enter the first TBU mode in response to a local TBU wake-up signal. The TBU transceiver 532 is configured to transmit a TBU system wake-up signal on either the TBU first system port or the TBU local port in response to the TBU local wake-up signal. The SBU second system port (e.g., 592) is adapted to receive the TBU system wake-up signal (e.g., in response to the TBU system wake-up signal being transmitted by TBU 530 via the TBU first system port).

[0091] In general, TBU 530 can detect wake-up signals on any of the first system port (e.g., 583), the second TBU system port (e.g., 593), and the TBU local port (e.g., 563). TBU 530 is configured to generate a subsequent wake-up signal (in response to a detected wake-up signal) to be transmitted to the port from which the detected wake-up signal was received. In the first scenario, a wake-up signal is detected via the TBU local port (e.g., 563), and in response, TBU transceiver 532 transmits a system wake-up signal via the first TBU system port (e.g., 583) and the second TBU system port (e.g., 593). In the second scenario, a wake-up signal is detected via a first system port of the TBU (e.g., 583), and in response, the TBU transceiver 532 transmits a system wake-up signal via a second system port of the TBU (e.g., 593) and a local wake-up signal via a local port of the TBU (e.g., 563). In the third scenario, a wake-up signal is detected via a second system port of the TBU (e.g., 593), and in response, the TBU transceiver 532 transmits a system wake-up signal via a first system port of the TBU (e.g., 583) and a local wake-up signal via a local port of the TBU (e.g., 563). In response to the TBU 532 receiving a system wake-up signal from either the SBU 510 or the third bus unit 530, it may transmit a local wake-up signal to the touch display 573, which may signal (e.g., command) the touch display to switch from power-saving mode to active mode.

[0092] The TBU controller 534 has a TBU energy detection input and a TBU wake-up output, the TBU wake-up output being coupled to the TBU wake-up input. The TBU controller 534 is configured to generate a TBU wake-up signal at the TBU wake-up output in response to the TBU energy detection signal.

[0093] The TBU energy detector 536 has a TBU energy detection output coupled to a TBU energy detection input. The TBU energy detector 536 is coupled to a TBU first system port (e.g., 583), a TBU second system port (e.g., 593), and a TBU local port (e.g., 563). The TBU energy detector 536 is configured to generate a TBU energy detection signal at the TBU energy detection output in response to a TBU detection of one of the following energies, received by the TBU transceiver 532 in TBU second mode: a TBU first system input signal (e.g., via node 583a), an optional TBU second system input signal (e.g., via bus 553), and a TBU local input signal (e.g., via node 563a).

[0094] In the first exemplary system, system 500 may further include additional (e.g., optional) bus units for extending the series-chained system bus. For example, a fourth bus unit 540 has a first system port (e.g., an upstream U-port 584), a second system port (e.g., a downstream D-port 594), a local port (e.g., a local L-port 564), a wake-up input, a transceiver 542, a controller 544, and an energy detector 546. The first system port (e.g., 584) is coupled to the second system port (e.g., 593) of the TBU.

[0095] A first system port (e.g., 584) is adapted to receive a first system input signal, an optional second system port (e.g., 594) may be adapted to receive a second system input signal, and a local port (e.g., 564) is adapted to receive a local input signal. Transceiver 542 is configured to transmit data of the first system input signal to one of the local port (e.g., 564) and the second system port (e.g., 594) in a first mode (e.g., active mode), and to conserve power in a second mode (e.g., power-saving mode). Transceiver 542 is configured to enter the first mode in response to a local wake-up signal. Transceiver 542 is configured to transmit a system wake-up signal at one of the first system port and the local port in response to a local wake-up signal. The second system port of the TBU (e.g., 593) is adapted to receive a fourth bus unit generated system wake-up signal (e.g., in response to the fourth bus unit system wake-up signal being transmitted by the fourth bus unit 540 via the first system port of the fourth bus unit).

[0096] The controller 544 has an energy detection input and a wake-up output, the wake-up output being coupled to the wake-up input. The controller 544 is configured to generate a local wake-up signal at the wake-up output in response to the energy detection signal.

[0097] The energy detector 546 has an energy detection output coupled to an energy detection input. The energy detector 546 is coupled to a first system port (e.g., 584), a second system port (e.g., 594), and a local port (e.g., 564). The energy detector 546 is configured to generate an energy detection signal at its energy detection output in response to the detection of one of the following energy signals, received by the transceiver 542 in a second mode: a first system input signal (e.g., via node 584a), an optional second system input signal (e.g., via bus 554), and a local input signal (e.g., via node 564a).

[0098] In the first exemplary system, system 500 further includes a user interface (UI) device, such as one of touch displays 572, 573, and 574. Touch display 572 is coupled to switch 527 (e.g., switch 427) of transceiver 522 of SBU 520 via cable 405 and local port 562; touch display 573 is coupled to switch 537 (e.g., switch 437) of transceiver 532 of TBU 530 via cable 407 and local port 563; and touch display 574 is coupled to switch 547 (e.g., switch 447) of transceiver 542 of fourth bus unit 540 via cable 409 and local port 564.

[0099] With respect to the FBU 510, the UI device (e.g., sensor 402 and head unit 401) includes a UI port (e.g., 560) coupled to the FBU local port (561), and the UI device is adapted to receive user input (such as user touch, user voice, user operation, proximity detection, and physical or electronic instructions). The FBU 510 is configured to generate a user wake-up signal at the UI port in response to user input. The FBU 510 is configured to generate an SBU system wake-up signal in response to the user wake-up signal. The SBU 520 is configured to generate an SBU local wake-up signal in response to the FBU system wake-up signal.

[0100] With respect to the SBU 520, a UI device (e.g., a touch display 572) includes a UI port (e.g., 405) coupled to an SBU local port (562), and the UI device is adapted to receive user input. The SBU 520 is configured to generate a user wake-up signal at the UI port in response to user input. The SBU 520 is configured to generate an SBU system wake-up signal in response to the user wake-up signal. The FBU 510 is configured to generate an FBU local wake-up signal in response to the SBU system wake-up signal, and the TBU 530 is configured to generate an FBU local wake-up signal in response to the SBU system wake-up signal.

[0101] With respect to the TBU 530, a UI device (e.g., a touch display 573) includes a UI port (e.g., 407) coupled to a TBU local port (563), and the UI device is adapted to receive user input. The TBU 530 is configured to generate a user wake-up signal at the UI port in response to user input. The TBU 530 is configured to generate a TBU system wake-up signal in response to the user wake-up signal. The SBU 520 is configured to generate an SBU local wake-up signal in response to the TBU system wake-up signal, and the fourth bus unit 540 is configured to generate a local wake-up signal for the fourth bus unit in response to the TBU system wake-up signal.

[0102] With respect to the fourth bus unit 540, a UI device (e.g., a touch display 574) includes a UI port (e.g., 409) coupled to a local port (564) of the fourth bus unit, and the UI device is adapted to receive user input. The fourth bus unit 540 is configured to generate a user wake-up signal at the UI port in response to user input. The fourth bus unit 540 is configured to generate a fourth bus unit system wake-up signal in response to the user wake-up signal. The TBU 530 is configured to generate a TBU local wake-up signal in response to the fourth bus unit system wake-up signal, and any additional bus units in a series chain are configured to generate their own local wake-up signals in response to the system wake-up signals of adjacent bus units in a series chain.

[0103] In the second exemplary system, system 500 includes a power management system 508. The power management system 508 includes power managers such as a PMIC (power manager integrated circuit) 518 coupled to FBU 510, a PMIC 528 coupled to SBU 520, a PMIC 538 coupled to TBU 520, and a PMIC 548 coupled to a fourth bus unit 540. PMICs 518, 528, 538, and 548 may be contained on a common substrate, and may be contained on a substrate containing bus units to which each PMIC and / or combination thereof are coupled. For example, power to operate the control of the power managers and energy sensing circuit elements may be provided (e.g., coupled) via a VDDKA (first power rail keep-alive) power signal (which reduces power consumption, for example, in a power-saving mode).

[0104] In the second exemplary system, system 500 includes a circuit (SBU 520, etc.) which includes a transceiver (e.g., 522), a controller (e.g., 524), and an energy detector (e.g., 526).

[0105] A transceiver (e.g., 522) has a first system port (e.g., one first selected from 582 and 592), a second system port (e.g., one second selected from 582 and 592, which is different from the first selected from 582 and 592), a local port (e.g., 562), and a wake-up input. The first system port is adapted to receive a first system input signal, the second system port is adapted to receive a second system input signal, and the local port is adapted to receive a local input signal. The transceiver is configured to transmit data of the first system input signal to the second system port in a first mode, to conserve power in a second mode, to enter the first mode in response to a local wake-up signal, and to transmit a system wake-up signal at the second system port in response to a local wake-up signal.

[0106] The controller (e.g., 524) has an energy sense input and a wake-up output, the wake-up output being coupled to the wake-up input. The controller is configured to generate a local wake-up signal at the wake-up output in response to the energy sense signal.

[0107] An energy detector (e.g., 526) has an energy detection output coupled to an energy detection input. The energy detector is coupled to a first system port and a local port. In a second mode, the energy detector is configured to generate an energy detection signal at the energy detection output in response to the detection of energy in either the first system input signal or the local input signal received by the transceiver.

[0108] In one example, the transceiver is further configured to transmit data of a second system input signal to a first system port in a first mode. In this example, the system wake-up signal may include a wake-up pattern.

[0109] In another example, the transceiver is further configured in a second mode to transmit a system wake-up signal on the first system port in response to a local wake-up signal.

[0110] In yet another example, the energy detector is configured to detect the energy of either a first system input signal or a local input signal. In this example, the energy detector may be coupled to a second system port and configured to detect the energy of a second system input signal. In this example, the energy detector is configured, in a second mode, to generate an energy detection signal at the energy detection output in response to the detection of the energy of a second system input signal received by a transceiver.

[0111] In a further example, the controller is further coupled to a first system port and a local port. The controller is further configured to detect a wake-up pattern in one of the first system input signals and local input signals in response to an energy detection signal. In this example, the controller may further include a data enable output, which is configured to generate a data enable signal at the data enable output in response to detection of a wake-up pattern in one of the first system input signals and local input signals. In this example, the energy detector may further include a data enable input and an enable power output, with the data enable input coupled to the data enable output, and the energy detector is further configured to generate an enable power signal at the enable power output. In this example, the circuit may further include a power manager, which includes an enable power input and a power supply output, with the enable power input coupled to the enable power output, and the power manager is configured to generate a power signal at the power supply output in response to an enable power signal. In this example, the controller may further include a power supply input, with the power supply input coupled to the power supply output, and the controller is further configured to generate a local wake-up signal in response to a power signal. In the example system, the power manager circuit may further include a logic enable output, the controller may further include a logic enable input, the logic enable input may be coupled to the logic enable output, the power manager may further be configured to generate a logic enable signal at the logic enable output in response to a power signal, and the controller may further be configured to generate a local wake-up signal in response to the logic enable signal.

[0112] Figure 6 is a flowchart illustrating an exemplary method for issuing a wake-up signal for the system illustrated in Figure 5. Exemplary method 600 may include various techniques described hereafter in this specification. In various implementations, the operations described do not necessarily have to be performed in the order described. In exemplary method 600, the method may begin at 605.

[0113] In 605, this method may include receiving a first wake-up signal by a first port of a first bus unit (FBU). For example, a first wake-up signal may be generated by a head unit 401 in response to a sensor 502. The first wake-up signal may be received by an FBU 510 at a local port 561. This method may continue in 610.

[0114] In 610, this method may include applying power to a second port of the FBU in response to a first wake-up signal. For example, a power management circuit element such as the PMIC 518 may couple operating power to a transmitter (e.g., transceiver 512), so that the transmitter can exit power-saving mode and enter active mode (e.g., where a signal can be transmitted). In one example, power may be coupled by energizing a power supply. In another example, an additional power is drawn in response to the system clock being activated (e.g., issued), so that the switching of active CMOS circuit elements is switched by the activated system clock. In one implementation, the entire bus unit may be placed into active mode by applying power to the active circuit elements of all bus units in response to a received wake-up signal. This method may be continued in 615.

[0115] In 615, this method may include transmitting a second wake-up signal from a second port of the FBU in response to a first wake-up signal. For example, the transmitter portion of transceiver 512 may transmit the second wake-up signal from a second port (e.g., the first system port 591). This method may be continued in 620.

[0116] In 620, this method may include receiving a second wake-up signal by a first port of a second bus unit (SBU). For example, the second wake-up signal may be generated by FBU 510 in response to the first wake-up signal. The second wake-up signal may be received by SBU 520 at the first system port 582. This method may be continued in 625.

[0117] In 625, this method may include applying power to a second port of the SBU in response to a second wake-up signal. For example, a power management circuit element such as PMIC 528 may couple operating power to a transmitter (e.g., transceiver 522), as a result the transmitter may exit power-saving mode and enter active mode (e.g., where a signal may be transmitted). This method may be continued in 630.

[0118] In 630, this method may include transmitting a third wake-up signal from a second port of the SBU in response to a second wake-up signal. For example, the transmitter portion of transceiver 522 may transmit a third wake-up signal from a second port (e.g., a second system port 592). The transmitter portion of transceiver 522 may optionally send a local wake-up signal from a third port (e.g., 562) to a locally coupled device (e.g., a touch display 572) in response to the second wake-up signal. This method may be continued in 635.

[0119] In 635, this method may include receiving a third wake-up signal by a first port of a third bus unit (TBU). For example, the third wake-up signal may be generated by SBU 520 in response to a second wake-up signal. The third wake-up signal may be received by TBU 530 at a first system port 582. This method may be continued in 625.

[0120] In 640, this method may include applying power to the TBU in response to a third wake-up signal. For example, a power management circuit element such as the PMIC 538 may couple operating power to the TBU 530, thereby allowing the TBU 530 to exit power-saving mode and enter active mode (where signals may be actively received and transmitted). Thus, in the system 500 described herein, a local wake-up event may be issued by traversing a series chain of bus units.

[0121] Figure 7 is a flowchart of an exemplary method for wake-up signal detection and wake-up signal processing of the system illustrated in Figure 5. Exemplary method 700 may include various techniques described hereafter in this specification. In various implementations, the operations described do not necessarily have to be performed in the order described. In exemplary method 700, this method may begin at 705.

[0122] In 705, this method may include monitoring a wake-up mode signal by an energy detector (e.g., 526). For example, the wake-up mode signal may be a VDDKA signal that can supply operating power to the energy detector of the bus unit. This method may be continued in 710.

[0123] If the wake-up mode signal is asserted at 710, this method continues at 715; otherwise, this method continues at 705.

[0124] In 715, this method may include monitoring the input signal for signal energy by an energy detector (e.g., 526). For example, the energy detector of the bus unit may detect quantized changes in the input signal by comparing the electric field strength, current, and / or voltage levels carried by a conductor to a threshold. The signal network (e.g., signal lines) may be a dedicated wake-up signal conductor or may be used for other purposes (e.g., a signal lane for receiving video stream information from an upstream source) while the bus unit is operating in active mode. This method may be continued in 720.

[0125] If signal energy is detected at 720, this method continues at 725; otherwise, this method continues at 705.

[0126] In 725, this method may include asserting an enable power signal by an energy detector (e.g., 526) in response to the detection of signal energy. This method continues in 730.

[0127] In 730, this method may include asserting an energy detection signal by an energy detector (e.g., 526) in response to the detection of signal energy. This method continues in 735.

[0128] In 735, this method may include the power management interface controller (e.g., 528) applying power to the bus unit controller (e.g., 524) in response to an asserted enable power signal. This method continues in 740.

[0129] In 740, this method may include asserting a logic enable signal by a power management interface controller (e.g., 528) in response to an enable power signal. For example, the logic enable signal may be asserted after a period of time following the application of power and allowing the controller's logic circuitry to stabilize. This method continues in 745.

[0130] In 745, this method may include a controller (e.g., 524) determining the start time of the valid detection period. For example, the controller may determine the start time of the valid detection period in response to a logic enable signal (e.g., start a timer). During this valid detection period, an input signal (e.g., a potential wake-up signal) is evaluated for valid data (e.g., a wake-up pattern). This method continues in 750.

[0131] In 750, this method may include a bus unit controller (e.g., 524) evaluating the received input signal for valid data. For example, the input signal may be evaluated to determine the presence of a wake-up pattern. The valid data may also include a wake-up code configured in the input signal to identify the bus unit from which the wake-up signal was received. The wake-up pattern may be encoded to reduce entropy (e.g., to reduce false positives due to injected noise). This method continues in 755.

[0132] At 755, if valid data is detected, this method continues at 780; otherwise, it continues at 760.

[0133] In step 760, if the valid detection period has expired (for example, the valid detection period has passed), this method continues in step 765; otherwise, this method continues in step 750.

[0134] In 765, this method may include indicating by the bus unit's controller (e.g., 524) that no valid data was found. This method continues in 770.

[0135] In 770, this method may include deasserting the enable power signal by an energy detector (e.g., 526) in response to an indication that no valid data was detected. For example, the enable power signal may be deasserted by negating an active-low signal (e.g., valid data). The active-low signal indicates that valid data was detected when it is active-low. This method continues in 775.

[0136] In 775, this method may include removing power from the bus unit's controller (e.g., 524) by a power management interface controller (e.g., 528) in response to a deasserted enable power signal. This method continues in 705.

[0137] In 780, this method may include a bus unit (e.g., bus unit 520, which is a first bus unit including an energy detector 526 and a controller 524) transmitting a wake-up signal (e.g., a second wake-up signal) to another bus unit (e.g., a second bus unit such as bus units 510 and / or 530). For example, the first bus unit may send a second wake-up signal to a second bus unit, the second wake-up signal being encoded using an identifier of the first bus unit, and the second bus unit being not the bus unit to which the first wake-up signal was sent. The wake-up signal may include a repeating pattern, and as a result, the wake-up signal may be transmitted (e.g., repeatedly transmitted) over an effective detection period. The length of the effective detection period (e.g., duration) may be selected for each bus unit. In one example, the wake pattern includes three start bits "101", four address bits "0010" (which indicate bus unit 520), and an even parity bit "1", resulting in a transmitted wake pattern that is a repeatable 8-bit pattern "10100101". When the received pattern does not contain the correct parity bits and does not contain the start bit "101", the data valid signal is deasserted by the controller 524 (e.g., set to high) to indicate that the received wake pattern is invalid, and as a result, the energy detector 526 does not assert the enable power signal in response to the invalid wake pattern.

[0138] Figure 8 is a block diagram of the first exemplary wake-up signal processing scenario in the exemplary system. In this example, system 800 includes series-chained bus units such as 810, 820, 830, and 840. The bus units may be deserializers (which may include both the series-connected and unseries-connected circuits themselves) and / or disaggregators (as described above in relation to Figure 4).

[0139] FBU810 may be similar to the multistream generator 410 and / or FBU510. FBU810 may be locally coupled to various devices (e.g., sensor 402 and head unit 401) and may generate local wake-up signals in response to inputs generated by any coupled sensor. FBU810 is upstream of SBU820 (e.g., with respect to most directions of video stream flow in the main channel of the system bus). FBU810 is coupled to SBU820 via cable 801. Cable 801 (and cables 802, 803, and 804, respectively) may be a cable harness containing conductors (e.g., twisted pair, coaxial, or optical fiber) for transmitting and / or receiving wake-up signals. In some examples, in active mode, a conductor reserved as a “lane” for video streaming may be used to transmit wake-up signals to a nearby bus unit in power-saving mode.

[0140] FBU810 is coupled to a second bus unit (SBU) 820 via cable 801. SBU820 is locally coupled to a touch display 826 (which may be similar to touch display 572) via cable 824, and SBU820 is configured to disaggregate video in active mode (by switch 822) and send the disaggregated stream to touch display 826. SBU820 is coupled to a third bus unit (TBU) 830 via cable 802. TBU830 is locally coupled to a touch display 836 (which may be similar to touch display 573) via cable 834, and TBU830 is configured to disaggregate video in active mode (by switch 832) and send the disaggregated stream to touch display 836. TBU830 is coupled to a fourth bus unit 840 via cable 803. A fourth bus unit 840 is locally coupled to a touch display 846 (which may be similar to a touch display 574) via cable 844, and the fourth bus unit 840 is configured to disaggregate video in active mode (by switch 842) and send the disaggregated stream to the touch display 846. The fourth bus unit 840 may be coupled to adjacent (e.g., downstream) bus units via cable 804 (and more downstream bus units may be chained in series along the system bus, with each additional downstream unit being locally coupled to similar circuitry).

[0141] In the first illustrative scenario, a first bus unit (e.g., FBU810) is configured to generate (e.g., transmit) a system wake-up signal 850 at a first time (e.g., time T0) in response to a user wake-up signal (e.g., generated by sensor 402 and head unit 401). The system wake-up signal 850 is generated at a first output (e.g., cable 801). A second bus unit (e.g., SBU820) is configured to generate (e.g., transmit) a system wake-up signal 851 at a second time (e.g., time T1 following the first time) in response to the system wake-up signal 850. The system wake-up signal 851 is generated at a second output (e.g., cable 802). A third bus unit (e.g., TBU830) is configured to generate (e.g., transmit) a system wake-up signal 852 in response to a system wake-up signal 851 during a third time (e.g., time T2 following the second time). The system wake-up signal 852 is generated at a third output (e.g., cable 803). A fourth bus unit (e.g., fourth bus unit 840) is configured to generate (e.g., transmit) a system wake-up signal 853 in response to a system wake-up signal 852 during a fourth time (e.g., time 3 following the third time). The system wake-up signal 853 is generated at a fourth output (e.g., cable 804).

[0142] Figure 9 is a block diagram of a second exemplary wake-up signal processing scenario in the exemplary system. In this example, system 900 includes a series-chained bus unit such as 910, 920, 930, and 940. The bus unit may be a deserializer and / or disaggregator.

[0143] FBU910 may be similar to the multistream generator 410 and / or FBU510. FBU910 may be locally coupled to various devices (e.g., sensor 402 and head unit 401) and may generate a local wake-up signal in response to inputs generated by any coupled sensor. FBU910 is upstream of SBU920. FBU910 is coupled to SBU920 via cable 901. Cable 901 (and each of cables 902, 903, and 904) may be a cable harness containing conductors for transmitting and / or receiving wake-up signals. In some examples, a conductor reserved as a “lane” for video streaming in active mode may be used to transmit a wake-up signal to a nearby bus unit in power-saving mode.

[0144] FBU910 is coupled to a second bus unit (SBU) 920 via cable 901. SBU920 is locally coupled to a touch display 926 (which may be similar to touch display 572) via cable 924, and SBU920 is configured to disaggregate video (by switch 922) in active mode and send the disaggregated stream to touch display 926. SBU920 is coupled to a third bus unit (TBU) 930 via cable 902. TBU930 is locally coupled to a touch display 936 (which may be similar to touch display 573) via cable 934, and TBU930 is configured to disaggregate video (by switch 932) in active mode and send the disaggregated stream to touch display 936. TBU930 is generated to a fourth bus unit 940 via cable 903. A fourth bus unit 940 is locally coupled to a touch display 946 (which may be similar to a touch display 574) via cable 944, and the fourth bus unit 940 is configured to disaggregate video in active mode (by switch 942) and send the disaggregated stream to the touch display 946. The fourth bus unit 940 may be coupled to adjacent (e.g., downstream) bus units via cable 904 (further downstream bus units may be chained in series along the system bus, and each of the additional downstream units may be locally coupled using similar circuitry).

[0145] In the second illustrative scenario, the first bus unit (e.g., SBU 920) is configured to generate (e.g., transmit) a system wake-up signal 950 at a first time (e.g., time T0) in response to a user wake-up signal (e.g., generated by a touch display 926). The system wake-up signal 950 is generated at a first output (e.g., cable 901). The first bus unit (e.g., SBU 920) is further configured to generate (e.g., transmit) a system wake-up signal 951 at a first time (e.g., time T0) in response to a user wake-up signal (e.g., generated by a touch display 926). The system wake-up signal 951 is generated at a second output (e.g., cable 902). A second bus unit (e.g., TBU930) is configured to generate (e.g., transmit) a system wake-up signal 952 in response to a system wake-up signal 951 during a second time (e.g., time T1 following the first time). The system wake-up signal 952 is generated at a third output (e.g., cable 903). A third bus unit (e.g., a fourth bus unit 940) is configured to generate (e.g., transmit) a system wake-up signal 953 in response to a system wake-up signal 952 during a third time (e.g., time T2 following the second time). The system wake-up signal 953 is generated at a fourth output (e.g., cable 904).

[0146] Figure 10 is a block diagram of a third exemplary wake-up signal processing scenario in the exemplary system. In this example, system 1000 includes series-chained bus units such as 1010, 1020, 1030, and 1040. The bus units may be deserializers and / or disaggregators.

[0147] FBU1010 may be similar to the multistream generator 410 and / or FBU510. FBU1010 may be locally coupled to various devices (e.g., sensor 402 and head unit 401) capable of generating a local wake-up signal in response to inputs generated by any coupled sensor. FBU1010 is upstream of SBU1020. FBU1010 is coupled to SBU1020 via cable 1001. Cable 1001 (and cables 1002, 1003, and 1004, respectively) may be a cable harness containing conductors for transmitting and / or receiving wake-up signals. In some examples, a conductor reserved as a “lane” for video streaming in active mode may be used to transmit a wake-up signal to a nearby bus unit in power-saving mode.

[0148] FBU1010 is coupled to a second bus unit (SBU) 1020 via cable 1001. SBU1020 is locally coupled to a touch display 1026 (which may be similar to touch display 572) via cable 1024, and SBU1020 is configured to disaggregate video in active mode (by switch 1022) and send the disaggregated stream to touch display 1026. SBU1020 is coupled to a third bus unit (TBU) 1030 via cable 1002. TBU1030 is locally coupled to a touch display 1036 (which may be similar to touch display 573) via cable 1034, and TBU1030 is configured to disaggregate video in active mode (by switch 1032) and send the disaggregated stream to touch display 1036. TBU 1030 is coupled to a fourth bus unit 1040 via cable 1003. The fourth bus unit 1040 is locally coupled to a touch display 1046 (which may be similar to touch display 574) via cable 1044, and the fourth bus unit 1040 is configured to disaggregate video in active mode (by switch 1042) and send the disaggregated stream to touch display 1046. The fourth bus unit 1040 may be coupled to adjacent (e.g., downstream) bus units via cable 1004 (where many more downstream bus units may be chained in series along the system bus, and each of the additional downstream units may be locally coupled using similar circuitry).

[0149] In the third illustrative scenario, the first bus unit (e.g., SBU 1030) is configured to generate (e.g., transmit) a system wake-up signal 1050 at a first time (e.g., time T0) in response to a user wake-up signal (e.g., generated by a touch display 1036). The system wake-up signal 1050 is generated at a first output (e.g., cable 1002). The first bus unit (e.g., SBU 1030) is further configured to generate (e.g., transmit) a system wake-up signal 1051 at a first time (e.g., time T0) in response to a user wake-up signal (e.g., generated by a touch display 1036). The system wake-up signal 1051 is generated at a second output (e.g., cable 1003). A second bus unit (e.g., TBU 1020) is configured to generate (e.g., transmit) a system wake-up signal 1052 in response to a system wake-up signal 1050 during a second time (e.g., time T1 following the first time). The system wake-up signal 1052 is generated at a third output (e.g., cable 1001). A third bus unit (e.g., a fourth bus unit 1040) is configured to generate (e.g., transmit) a system wake-up signal 1053 in response to a system wake-up signal 1051 during a second time (e.g., time T1 following the first time). The system wake-up signal 1053 is generated at a fourth output (e.g., cable 1004).

[0150] Figure 11 is a block diagram of another exemplary system that includes at least one stream disaggregator adapted to selectively forward transmissions between serially linked devices. For example, system 1100 is an exemplary system that includes a source 1101, a serializer 1110 (coupled to source 1101 via cable 1102), a deserializer 1120 (locally coupled to local display 1104 via cable 1105, for example), a deserializer 1130 (locally coupled to local display 1106 via cable 1107, for example), and a deserializer 1140 (locally coupled to local display 1108 via cable 1109, for example).

[0151] Cables 1111, 1112, and 1113 each contain a physical medium through which a system protocol (e.g., a system bus) is implemented. The system protocol can be either unidirectional or bidirectional. In an implementation of a bidirectional system protocol, a first bidirectional serial link is established between serializer 1110 and deserializer 1120 via cable 1111 (which is coupled between serializer 1110 and deserializer 1120), a second bidirectional serial link is established between deserializer 1120 and deserializer 1130 via cable 1112 (which is coupled between deserializer 1120 and deserializer 1130), and a third bidirectional serial link is established between deserializer 1130 and deserializer 1140 via cable 1113 (which is coupled between deserializer 1130 and deserializer 1140).

[0152] A bidirectional serial link can be either asymmetric or symmetric. An exemplary asymmetric bidirectional link includes an upstream rate of 165 megabits per second (e.g., for bit traffic directed towards serializer 1110) and a downstream rate of 13 gigabits per second (e.g., for bit traffic away from serializer 1110). The asymmetrical rates enable high-speed downstream transmission of high-resolution video (e.g., for transmitting various high-resolution video streams to a selected display), while also providing a robust bidirectional system control and communication link between devices. The exemplary asymmetric bidirectional link includes symmetric data rates, so that data can be transmitted at full rate in either direction.

[0153] In one example, source 1101 is a source such as a head unit 401. Source 1101 is coupled to serializer 1110 via cable 1102. Cable 1102 is configured to carry at least one video stream according to a protocol such as MIPI CIS.

[0154] In this example, serializer 1110 is a serializer such as multistream generator 410. Serializer 1110 includes transmitter 1190 such as transmitter 390, which is adapted to transmit a multistream (for example, this includes formatted information of at least one video stream generated by serializer 1110 and carried over cable 1102), and as a result, deserializer 1120 can receive and process (for example, process a portion thereof) the transmitted multistream.

[0155] In this example, the deserializer 1120 is a deserializer such as a stream disaggregator 420. The deserializer 1120 is coupled to the serializer 1110 via cable 1111. The deserializer 1120 includes a receiver 1122 (receiver 422, etc.) configured to receive information transmitted by the transmitter 1190. The deserializer 1120 includes a transmitter 1126 (stream forwarder 426, etc.) configured to transmit the information received from the transmitter 1190. Cable 1111 is configured to carry the multistream output transmitted by the transmitter 1190 according to a protocol such as FPD-Link IV. The deserializer 1120 is locally coupled to a local display 1104 (local display 404, etc.) via cable 1105. Cable 1105 is configured to carry the selected video stream according to a protocol such as eDP (Enhanced Display Protocol).

[0156] In this example, the deserializer 1130 is a deserializer such as a stream disaggregator 430. The deserializer 1130 is coupled to the serializer 1120 via cable 1112. The deserializer 1130 includes a receiver 1132 (receiver 422, etc.) configured to receive information transmitted by the transmitter 1126. The deserializer 1130 includes a transmitter 1136 (stream forwarder 426, etc.) configured to transmit the information received from the transmitter 1126. Cable 1112 is configured to carry the multistream output transmitted by the transmitter 1126 according to a protocol such as FPD-Link IV. The deserializer 1130 is locally coupled to a local display 1106 (local display 406, etc.) via cable 1107. Cable 1107 is configured to carry the selected video stream according to a protocol such as eDP.

[0157] In this example, the deserializer 1140 is a deserializer such as a stream disaggregator 440. The deserializer 1140 is coupled to the serializer 1130 via cable 1113. The deserializer 1140 includes a receiver 1142 (receiver 422, etc.) configured to transmit information transmitted by the transmitter 1136. The deserializer 1140 optionally includes a transmitter 1146 (stream forwarder 426, etc.) configured to transmit information received from the transmitter 1136. Cable 1113 is configured to carry the multistream output transmitted by the transmitter 1136 according to a protocol such as FPD-Link IV. The deserializer 1140 is locally coupled to a local display 1108 (local display 408, etc.) via cable 1109. Cable 1109 is configured to carry the selected video stream according to a protocol such as eDP.

[0158] For example, if the last deserializer in a chain only receives data that is intended to be displayed on each local display locally coupled to the last deserializer (e.g., addressed data), then the last deserializer does not need to include a switch such as switch 427.

[0159] Modifications to the described embodiments are possible within the scope of the claims, and other embodiments are possible.

Claims

1. It is a circuit, Transceiver and, Controller and Energy detector and Includes, The transceiver has a first system port, a second system port, a local port, and a wake-up input, wherein the first system port is adapted to receive a first system input signal, the second system port is adapted to receive a second system input signal, and the local port is adapted to receive a local input signal. The transceiver is configured to transmit data of the first system input signal to the second system port in a first mode, to be configured to conserve power in a second mode, to enter the first mode in response to a local wake-up signal, and to transmit a system wake-up signal at the second system port in response to the local wake-up signal. The controller has an energy detection input and a wake-up output, the wake-up output is coupled to the wake-up input, and the controller is configured to generate the local wake-up signal at the wake-up output in response to the energy detection signal. A circuit in which the energy detector has an energy detection output coupled to the energy detection input, the energy detector is coupled to the first system port and the local port, and the energy detector is configured in the second mode to generate the energy detection signal at the energy detection output in response to the detection of one of the energy of the first system input signal and the local input signal received by the transceiver.

2. The circuit according to claim 1, A circuit in which the transceiver is further configured to transmit data of the second system input signal to the first system port in the first mode.

3. The circuit according to claim 2, A circuit in which the system wake-up signal includes a wake-up pattern.

4. The circuit according to claim 1, A circuit in which the transceiver is further configured to transmit the system wake-up signal at the first system port in response to the local wake-up signal in the second mode.

5. The circuit according to claim 1, A circuit in which the energy detector is configured to detect the energy of one of the first system input signal and the local input signal.

6. The circuit according to claim 5, A circuit in which the energy detector is coupled to the second system port and configured to detect the energy of the second system input signal.

7. The circuit according to claim 6, A circuit in which the energy detector is configured to generate the energy detection signal at the energy detection output in response to the detection of the energy of the second system input signal received by the transceiver in the second mode.

8. The circuit according to claim 1, A circuit in which the controller is further coupled to the first system port and the local port, and the controller is further configured to detect a wake-up pattern in one of the first system input signal and the local input signal in response to the energy detection signal.

9. The circuit according to claim 8, A circuit in which the controller further includes a data enable output, and the controller is configured to generate a data enable signal at the data enable output in response to detection of the wake-up pattern in one of the first system input signal and the local input signal.

10. The circuit according to claim 9, A circuit in which the energy detector further includes a data enable input and an enable power output, the data enable input being coupled to the data enable output, and the energy detector is further configured to generate an enable power signal at the enable power output.

11. The circuit according to claim 10, A circuit further comprising a power manager, the power manager comprising an enable power input and a power supply output, the enable power input coupled to the enable power output, and the power manager configured to generate a power signal at the power supply output in response to the enable power signal.

12. The circuit according to claim 11, A circuit wherein the controller further includes a power supply input, the power supply input is coupled to the power supply output, and the controller is further configured to generate the local wake-up signal in response to the power signal.

13. The circuit according to claim 12, A circuit wherein the power manager further includes a logic enable output, the controller further includes a logic enable input, the logic enable input is coupled to the logic enable output, the power manager is further configured to generate a logic enable signal at the logic enable output in response to the power signal, and the controller is further configured to generate the local wake-up signal in response to the logic enable signal.

14. It is a system, The first bus unit (FBU), The second bus unit (SBU), Includes, The FBU comprises an FBU first system port, an FBU local port, an FBU wake-up input, an FBU transceiver, an FBU controller, and an FBU energy detector. The FBU transceiver is coupled to the FBU first system port, the FBU local port, and the FBU wake-up input, and the FBU first system port is adapted to receive the FBU first system input signal, the FBU local port is adapted to receive the FBU local input signal, the FBU transceiver is configured to transmit the data of the FBU first system input signal to the FBU local port in FBU first mode, the FBU transceiver is configured to conserve power in FBU second mode, the FBU transceiver is configured to enter FBU first mode in response to the FBU local wake-up signal, and the FBU transceiver is configured to transmit the FBU system wake-up signal in response to the FBU local wake-up signal at one of the FBU first system port and the FBU local port. The FBU controller has an FBU energy detection input and an FBU wake-up output, the FBU wake-up output is coupled to the FBU wake-up input, and the FBU controller is configured to generate the FBU local wake-up signal at the FBU wake-up output in response to the FBU energy detection signal. The FBU energy detector has an FBU energy detection output coupled to the FBU energy detection input, the FBU energy detector is coupled to the FBU first system port and the FBU local port, and the FBU energy detector is configured to generate the FBU energy detection signal at the FBU energy detection output in response to the FBU detection of one of the energy signals from the FBU first system input signal and the FBU local input signal received by the FBU transceiver in the FBU second mode. A system in which the SBU has an SBU first system port, the SBU first system port is coupled to the FBU first system port, the SBU first system port is adapted to receive the FBU system wake-up signal, and the FBU first system port is adapted to receive the SBU system wake-up signal generated by the SBU.

15. The system according to claim 14, The SBU further includes a second system port of the SBU, a local port of the SBU, an SBU wake-up input, an SBU transceiver, an SBU controller, and an SBU energy detector. The SBU transceiver is coupled to the SBU first system port, the SBU second system port, the SBU local port, and the SBU wake-up input, and is configured so that the SBU first system port receives the SBU first system input signal. The system port of the second SBU is adapted to receive the system input signal of the second SBU. The aforementioned SBU local port is adapted to receive SBU local input signals, The SBU transceiver is configured to transmit data of the SBU first system input signal to the SBU second system port in SBU first mode, to conserve power in SBU second mode, to enter SBU first mode in response to an SBU local wake-up signal, and to transmit the SBU system wake-up signal at one of the SBU first system port and the SBU second system port in response to the SBU local wake-up signal. The SBU controller has an SBU energy detection input and an SBU wake-up output, the SBU wake-up output is coupled to the SBU wake-up input, and the SBU controller is configured to generate the SBU local wake-up signal at the SBU wake-up output in response to the SBU energy detection signal. A system in which the SBU energy detector has an SBU energy detection output coupled to the SBU energy detection input, the SBU energy detector is coupled to the SBU first system port, the SBU second system port, and the SBU local port, and the SBU energy detector is configured to generate the SBU energy detection signal at the SBU energy detection output in response to the SBU detection of one of the energy of the SBU first system input signal, the SBU second system input signal, and the SBU local input signal received by the SBU transceiver in the SBU second mode.

16. The system according to claim 15, The system further includes a third bus unit (TBU) having a first TBU system port, a TBU local port, a TBU wake-up input, a TBU transceiver, a TBU controller, and a TBU energy detector. The first system port of the TBU is coupled to the second system port of the SBU, and the first system port of the TBU is adapted to receive the SBU system wake-up signal. The TBU transceiver is coupled to the TBU first system port, the TBU local port, and the TBU wake-up input, and is adapted so that the TBU first system port receives the TBU first system input signal. The TBU local port is adapted to receive a TBU local input signal, the TBU transceiver is configured to transmit data of the TBU first system input signal to the TBU local port in TBU first mode, the TBU transceiver is configured to conserve power in TBU second mode, the TBU transceiver is configured to enter TBU first mode in response to a TBU local wake-up signal, and the TBU transceiver is configured to transmit a TBU system wake-up signal in one of the TBU first system port and one of the TBU local ports in response to the TBU local wake-up signal. The TBU controller has a TBU energy detection input and a TBU wake-up output, the TBU wake-up output is coupled to the TBU wake-up input, and the TBU controller is configured to generate the TBU local wake-up signal at the TBU wake-up output in response to the TBU energy detection signal. A system in which the TBU energy detector has a TBU energy detection output coupled to the TBU energy detection input, the TBU energy detector is coupled to the TBU first system port and the TBU local port, and the TBU energy detector is configured to generate the TBU energy detection signal at the TBU energy detection output in response to the TBU detection of one of the energy of the TBU first system input signal and the TBU local input signal received by the TBU transceiver in the TBU second mode.

17. The system according to claim 16, A system further comprising a user interface (UI) device, the UI device including a UI port coupled to the SBU local port, the UI device being adapted to receive user input, the SBU being configured to generate a user wake-up signal at the UI port in response to the user input, the SBU being configured to generate the SBU system wake-up signal in response to the user wake-up signal, the FBU being configured to generate the FBU local wake-up signal in response to the SBU system wake-up signal, and the TBU being configured to generate the FBU local wake-up signal in response to the SBU system wake-up signal.

18. It is a method, The first bus unit (FBU) transceiver receives the SBU system wake-up signal transmitted by the second bus unit (SBU) from the first system port of the SBU, In SBU mode 1, the SBU transceiver transmits the data of the SBU system input signal 1 to the SBU system port 2. In the second SBU mode, power saving is performed by the SBU, wherein the SBU transceiver is configured to switch from the second SBU mode to the first SBU mode in response to an SBU local wake-up signal. In response to the SBU local wake-up signal, the SBU transceiver transmits an SBU system wake-up signal at the SBU first system port. In response to the SBU energy detection signal, the SBU controller generates the SBU local wake-up signal, The energy of one of the SBU second system input signal and SBU local input signal received by the SBU transceiver in the SBU second mode is detected by the SBU energy detector. The SBU energy detector generates the SBU energy detection signal in response to the detection of one of the SBU second system input signal and the SBU local input signal by the SBU energy detector, wherein in the SBU second mode, one of the SBU second system input signal and the SBU local input signal is received by the SBU transceiver. The SBU system wake-up signal is transmitted by the SBU transceiver at the first system port of the SBU, Methods that include...

19. The method according to claim 18, A method further comprising transmitting the SBU system wake-up signal at the second system port of the SBU using the SBU transceiver.

20. The method according to claim 19, A method further comprising: having a third bus unit (TBU) receive the SBU system wake-up signal transmitted via the second system port of the SBU; and having the TBU generate a TBU wake-up signal.

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