阅读说明：本技术 串行链接的装置之间的选定模式信号转发 (Selected mode signal forwarding between serially linked devices ) 是由 维吉亚·采卡拉 刘鑫 于 2020-05-26 设计创作，主要内容包括：在所描述实例中,电路(500)调适成在本地端口(562)或第一系统端口(582)处接收输入信号。收发器(522)配置成响应于本地唤醒信号而进入第一模式,且配置成响应于所述本地唤醒信号而在第二系统端口(592)处发射系统唤醒信号。控制器(524)配置成响应于能量检测信号而产生所述本地唤醒信号。能量检测器(526)耦合到所述第一系统端口(582)和所述本地端口(562),且配置成响应于检测到在第二模式中由所述收发器(522)接收的第一系统输入信号和本地输入信号中的一者的能量而产生所述能量检测信号。(In described examples, the circuit (500) is adapted to receive an input signal at the local port (562) or the first system port (582). The transceiver (522) is configured to enter a first mode in response to a local wake-up signal and is configured 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 the 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 to generate the energy detection signal in response to detecting energy of one of a first system input signal and a local input signal received by the transceiver (522) in a second mode.)

1. A circuit, comprising:

a transceiver having a first system port adapted to receive a first system input signal, a second system port adapted to receive a second system input signal, a local port adapted to receive a local input signal, and a wake-up input, the transceiver configured to communicate data of the first system input signal to the second system port in a first mode, the transceiver configured to conserve power in a second mode, the transceiver configured to enter the first mode in response to a local wake-up signal, and the transceiver configured to transmit a system wake-up signal at the second system port in response to the local wake-up signal;

a controller having an energy detection input and a wake-up output, the wake-up output coupled to the wake-up input, and the controller configured to generate the local wake-up signal at the wake-up output in response to an energy detection signal; and

an energy detector having an energy detection output coupled to the energy detection input, the energy detector coupled to the first system port and the local port, wherein the energy detector is configured to generate the energy detection signal at the energy detection output in response to detecting energy of one of the first system input signal and the local input signal received by the transceiver in the second mode.

2. The circuit of claim 1, wherein the transceiver is further configured to communicate data of the second system input signal to the first system port in the first mode.

3. The circuit of claim 2, wherein the system wake-up signal includes a wake-up pattern.

4. The circuit of claim 1, wherein 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 of claim 1, wherein the energy detector is configured to detect energy of one of the first system input signal and the local input signal.

6. The circuit of claim 5, wherein the energy detector is coupled to the second system port, the energy detector configured to detect energy of the second system input signal.

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

8. The circuit of claim 1, wherein the controller is further coupled to the first system port and the local port, the controller 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 of claim 8, wherein the controller further comprises a data valid output, the controller configured to generate a data valid signal at the data valid output in response to detecting the wake-up pattern in one of the first system input signal and the local input signal.

10. The circuit of claim 9, wherein the energy detector further comprises a data valid input and an enable power output, the data valid input coupled to the data valid output, the energy detector further configured to generate an enable power signal at the enable power output.

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

12. The circuit of claim 11, wherein the controller further comprises a power supply input coupled to the power supply output, the controller further configured to generate the local wake-up signal in response to the power signal.

13. The circuit of claim 12, wherein the power manager further comprises a logic enable output, the controller further comprising a logic enable input coupled to the logic enable output, the power manager further configured to generate a logic enable signal at the logic enable output in response to the power signal, the controller further generating the local wake-up signal in response to the logic enable signal.

14. A system, comprising:

a First Bus Unit (FBU) having 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 coupled to the FBU first system port, the FBU local port, and the FBU wake-up input, the FBU first system port adapted to receive an FBU first system input signal, the FBU local port adapted to receive an FBU local input signal, the FBU transceiver configured to communicate data of the FBU first system input signal to the FBU local port in an FBU first mode, the FBU transceiver configured to save power in an FBU second mode, the FBU transceiver configured to enter the FBU first mode in response to an FBU local wake-up signal, the FBU transceiver configured to transmit a U system wake-up signal at one of the FBU first system port and the FBU local port in response to the FBU local wake-up signal, the FBU controller having an FBU energy detection input and an FBU wake-up output, the FBU wake-up output coupled to the FBU wake-up input, and the FBU controller configured to generate the FBU local wake-up signal at the FBU wake-up output in response to an FBU energy detection signal, the FBU energy detector having an FBU energy detection output coupled to the FBU energy detection input, the FBU energy detector coupled to the FBU first system port and the FBU local port, wherein the FBU energy detector is configured to generate the FBU energy detection signal at the FBU energy detection output in response to an FBU detection of energy of one of the FBU first system input signal and the FBU local input signal received by the FBU transceiver in the FBU second mode; and

a Second Bus Unit (SBU) having an SBU first system port coupled to the FBU first system port, the SBU first system port adapted to receive the FBU system wake-up signal, and the FBU first system port adapted to receive an SBU system wake-up signal generated by the SBU.

15. The system of claim 14, wherein the SBU further comprises an SBU second system port, an SBU local port, 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, the SBU first system port is adapted to receive an SBU first system input signal, the SBU second system port is adapted to receive an SBU second system input signal, the SBU local port is adapted to receive an SBU local input signal, the SBU transceiver is configured to transmit data of the SBU first system input signal to the SBU second system port in an SBU first mode, the SBU transceiver is configured to save power in an SBU second mode, the SBU transceiver is configured to enter the SBU first mode in response to an SBU local wake-up signal, and the SBU transceiver is configured 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 an SBU energy detection signal, 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, wherein the SBU energy detector is configured to respond to the SBU first system input signal, the SBU second system port, and the SBU local port received by the SBU transceiver in the SBU second mode, An SBU detection of energy of one of the SBU second system input signal and the SBU local input signal, the SBU energy detection signal generated at the SBU energy detection output.

16. The system of claim 15, further comprising a Third Bus Unit (TBU) having a TBU first system port coupled to the SBU second system port, a TBU local port adapted to receive the SBU system wake-up signal, a TBU wake-up input, a TBU transceiver coupled to the TBU first system port, the TBU local port, and the TBU wake-up input, a TBU controller, and a TBU energy detector, the TBU first system port adapted to receive a TBU first system input signal, the TBU local port adapted to receive a TBU local input signal, the TBU transceiver configured to transmit data of the TBU first system input signal to the TBU local port in a TBU first mode, the TBU transceiver configured to save power in a TBU second mode, the TBU transceiver is configured to enter the 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 at one of the TBU first system port and the TBU local port in response to the TBU local wake-up signal, the TBU controller having a TBU energy detection input and a TBU wake-up output, the TBU wake-up output coupled to the TBU wake-up input, and the TBU controller configured to generate the TBU local wake-up signal at the TBU wake-up output in response to a TBU energy detection signal, the TBU energy detector having a TBU energy detection output coupled to the TBU energy detection input, the TBU energy detector coupled to the TBU first system port and the TBU local port, wherein the TBU energy detector is configured to respond to the TBU first system input signal and the TBU local input signal received by the TBU transceiver in the TBU second mode TBU detection of the energy of one of the signals, the TBU energy detection signal being generated at the TBU energy detection output.

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

18. A method, comprising:

receiving, by a First Bus Unit (FBU) transceiver from a Second Bus Unit (SBU) first system port, an SBU system wake-up signal transmitted by the SBU;

transmitting data of an SBU first system input signal to an SBU second system port in an SBU first mode through an SBU transceiver;

the SBU saves power in an SBU second mode, wherein the SBU transceiver is configured to enter the SBU first mode from the SBU second mode in response to an SBU local wake-up signal;

transmitting, by the SBU transceiver, an SBU system wake-up signal at the SBU first system port in response to the SBU local wake-up signal;

generating, by an SBU controller, the SBU local wake-up signal in response to an SBU energy detection signal;

detecting, by an SBU energy detector, an energy of one of an SBU second system input signal and an SBU local input signal received by the SBU transceiver in the SBU second mode;

generating the SBU energy detection signal in response to the SBU energy detector detecting one of the SBU second system input signal and the SBU local input signal, the one of the SBU second system input signal and the SBU local input signal being received by the SBU transceiver in the SBU second mode; and

and transmitting the SBU system wake-up signal at the first system port of the SBU through the SBU transceiver.

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

20. The method of claim 19, further comprising receiving, by a Third Bus Unit (TBU), the SBU system wake-up signal transmitted via the SBU second system port, and generating, by the TBU, a TBU wake-up signal.

Background

In some electronic systems, the various components are coupled by a physical layer that may include connectors and wires. In some applications, the limits on the functionality of the various components may be constrained by the cost, size, and number of connectors and/or the cost, size, and number of individual wires in the wire.

Disclosure of Invention

In described examples, a 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 is configured to transmit a system wake-up signal at the 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 the energy detection signal. An energy detector is coupled to the first system port and the local port and configured to generate an energy detection signal in response to detecting energy of one of the first system input signal and the local input signal received by the transceiver in the second mode.

Drawings

FIG. 1 is a system diagram showing an example vehicle including an example system adapted to selectively forward transmissions between serially linked devices of the example system.

Fig. 2 is a diagram of an example transmission in an example system adapted to selectively forward transmissions between serially linked devices.

Fig. 3 is a block diagram of an example multi-stream generator adapted to aggregate input streams in an example system adapted to selectively forward transmissions between serially linked devices.

Fig. 4 is a block diagram of an example system including at least one current divider adapted to selectively forward transmissions between serially linked devices.

Fig. 5 is a block diagram of an example system including at least one bus unit adapted to generate and forward a system wake-up signal between serially linked bus units.

Fig. 6 is a flow diagram of an example method of wake-up signal publication for the example system of fig. 5.

Fig. 7 is a flow diagram of an example method wake-up signal detection and wake-up signal processing of the example system of fig. 5.

FIG. 8 is a block diagram of a first example wake-up signal processing scenario in an example system.

FIG. 9 is a block diagram of a second example wake-up signal processing scenario in an example system.

FIG. 10 is a block diagram of a third example wake-up signal processing scenario in an example system.

Fig. 11 is a block diagram of another example system including at least one current divider adapted to selectively forward transmissions between serially linked devices.

Detailed Description

In the drawings, like reference numerals refer to like elements, and the various features are not necessarily drawn to scale.

Various electronic systems employ components that are coupled together to comprise the system. As the functionality of the system increases, the complexity of the interconnect increases. As more functionality is added to the system (e.g., in response to increased integration and processing capabilities), the number of terminals of the connector increases, which in turn increases the size, complexity, and/or cost of the connector.

Some electronic systems may be installed in a transportation platform (e.g., an aircraft or a motor vehicle). Limitations in the structure of mobile platforms (e.g., due to human factors, safety considerations, and aerodynamic performance) may limit the space that cable lines to connectors and electronic systems would otherwise provide. Furthermore, access to connectors and cables (e.g., for testing, replacement, and/or repair) may be limited (which may increase operating costs), such as when the electronic system is installed in an instrument panel of a vehicle (which may include at least one airbag).

An example of an electronic system that may be installed in a mobile platform is an in-vehicle "infotainment" system in which video data may be generated by (or otherwise transmitted by) a control unit, such as a head-mounted unit or other data source. The generated video data may be transmitted to multiple display panels (e.g., heads-up display, dashboard, and center instrument display). In order to send different types of display data from the control unit to the different displays, various cables/connectors are arranged between the control unit and each of the different displays. A cable adapted to transmit 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 bundle (e.g., a flexible cable bundle) having insulated wires arranged to electrically couple signals (e.g., bidirectional and/or unidirectional signals) between the first connector and the second connector.

In an example, the plurality of displays can be connected to the control unit in a one-to-many configuration, where the connection cables converge at a single location on the control unit (e.g., a surface of the control unit). For example, the master unit may include a connector and cable pair for communicating with each slave device of the system (e.g., in a star network topology). The convergence of connectors and cables at the control unit creates a mechanical spacing problem, wherein the convergence of multiple connectors positioned side-by-side occupies a considerable space in the motor vehicle. Further, the video information (e.g., at least one video stream) from the control unit is high resolution data that is serially streamed to the respective display via the respective connector/cable pair. Because of the point-to-point connection of the star topology, each video stream need not be associated or otherwise identified with a network address. Typically, the video data from the head unit being transmitted to the display is high resolution data that is continuously streamed, and not in an easily networkable format when in some other data networking applications.

As described herein, the example system is adapted to selectively forward transmissions between serially linked devices of the example system. For example, an example system may include a control unit coupled to a serial chain of display units (e.g., one end of the serial chain). An example multi-stream generator may be coupled to an output of the control unit such that the example multi-stream generator may encode (e.g., package) video data from multiple streams into a format that may be applicable to different types of displays in a serial chain (e.g., daisy-chained displays). The mechanical spacing problem of plugging due to cable/connector convergence at the control unit location can be reduced by arranging the example system components as shown in fig. 1.

FIG. 1 is a system diagram showing an example vehicle including an example system adapted to selectively forward transmissions between serially linked devices of the example system. Generally, the system 100 is an example system that includes a host vehicle 110. Example multiple display systems 120 may be installed in a host vehicle 110. Example multiple display systems 120 may include any number of displays in a serial chain, one end of which may be connected to a control unit.

The example plurality of display systems 120 may include a control unit (e.g., a head unit 122), a first display (e.g., an instrument panel display, CLUSTER, 124), a second display (e.g., a heads-up display, HUD, 126), and a third display (e.g., a center instrument display, CID, 128). An example multiple display system may include one or more head units 122. Head unit 122 is adapted to receive sensor data (e.g., from a camera or instrument sensor) and generate a video stream in response to the sensor data. Each head unit 122 transmits at least one generated video stream, each of which is received by the multi-stream generator 123. However, the use of multiple head units increases system complexity, creates additional failed nodes, increases cost, and takes up more space, for example, in a confined area.

Multi-current generator 123(MG) may have an input (e.g., a video input) coupled to (e.g., may be included by) head unit 122, and may have an output coupled to an input of shunt 125 (e.g., via cable 133). In an example, the multi-stream generator 123 can receive video streams from respective head units 122. In some examples, the multi-stream generator 123 may receive video streams from at least one head unit 122 (e.g., such that one or more video streams may be generated by the head unit 122 for stream aggregation by the multi-stream generator 123).

The shunt 125 may have a first output (e.g., a local output) coupled to (e.g., may be included by) the display CLUSTER 124, and may have a second output (e.g., a system output) coupled to an input of the shunt 127 (e.g., via a cable 135).

The splitter 127 may have a first output (e.g., a local output) coupled to (e.g., may be included by) the display HUD 126, and may have a second output (e.g., a system output) coupled to an input of the splitter 129 (e.g., via a cable 137).

The splitter 129(SD) may have a first output (e.g., a local output) coupled to (e.g., may be included by) the display CID 128, and may have a second output (e.g., a system output) optionally coupled to an input of the optional splitter (not shown) (e.g., via another cable, not shown) for display. Other shunts may be serially connected to the tail of the serial chain connecting the serially linked displays (e.g., where the tail of the serial chain is opposite the end of the serial chain connected to head unit 122). (example Cable network is described below with respect to FIG. 4.)

The serially linked display system described herein reduces spatial and mechanical constraints (e.g., such that constraints are reduced to having space to connect separate connectors/cables at the head unit 122) compared to a star topology display system for three displays, which includes three cables and corresponding connectors that converge at the location of the control unit.

The multi-stream generator 123 is arranged to encode high resolution real-time video data (including data associated with the video) into a packet format. The operation of the multi-stream generator is described below with reference to fig. 3. The multi-stream generator 123 may be arranged as a serializer (e.g., adapted to continuously output video data, wherein the video data may be asynchronously received by the multi-stream generator 123 in a serial or parallel format) and/or may be arranged to output the video data in a parallel manner. Each packet may include an identifier (e.g., a stream identifier) for identifying the particular video stream being encoded and/or for identifying the destination of the packet (e.g., identifying the display to which the packet is addressed). The identifier may be resolved by the diverter according to a mode (e.g., a default or programmed configuration) associated with the respective diverter. Each packet is received by at least one splitter for forwarding (and/or decoding/deserializing).

The splitters (e.g., 133, 135 and 137) are arranged to receive a packet (e.g., having an identifier for indicating a destination display) and select between a splitter first output (e.g., a local output for coupling information to a locally coupled display) and a splitter second output (e.g., a system output for forwarding information to at least one other splitter).

Fig. 2 is a diagram of an example transmission in an example system adapted to selectively forward transmissions between serially linked devices. In general, transmission 200 is an example transmission arranged in a packet format. An example transmission may include streaming data for streaming video. The streaming video data may include audio data coupled to (e.g., synchronized with) the streaming video. The streaming data may contain content for displaying moving and/or still images.

In a first example packet, such as 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 Continuous (CONT) field 216.

The field 211 may indicate whether the stream payload (e.g., field 212) contains command data or stream data. The command data contained by field 212 may include: a start command, for example, for starting playing a selected video stream; a configuration command, for example, for configuring a mode, selecting a particular protocol (e.g., from among various proprietary or industry standards) through which a particular splitter communicates with a connected local display (e.g., a directional cable connected local display), setting a playback channel for the particular display (e.g., for playing at least one selected stream containing a selected STRM field 214 value); a routing command for selecting at least one stream (e.g., a stream of a particular splitter) to be routed to a local display; and/or a forwarding command for selecting at least one flow to be forwarded to another splitter (e.g., causing a first depolymer to forward the selected flow to a second splitter downstream of the first splitter and head unit). In an example, configuration data can be pre-programmed (e.g., at system integration, such as at an automobile factory) to a particular diverter (e.g., such that configuration time is reduced), and command data can be used in operation to re-program a given configuration (e.g., whether the given configuration is pre-programmed or programmed in operation).

The streaming data contained by field 212 may contain video (e.g., still or motion video) information, audio information, or a combination thereof. The resolution of the streaming data may be selected to provide video (and/or sound) quality commensurate with the particular display and/or target function. The streaming 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 a video frame 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 and subsequent decoding by a target display. The video frames may be streamed (e.g., transmitted as a time sequence of video frames associated with a particular video "feed").

The field 213 contains an ECC code (e.g., for error detection and correction). The number of bits of field 213 may be increased (e.g., from one parity bit to a larger number of bits) to increase the level of detection and even correction of errors that may occur in the packets 210 being transmitted and received. The receiver may evaluate the ECC code of the received packet against other bits of the received packet, such as to correct a corrupted packet and/or to request retransmission of the original packet (e.g., original packet data), such as by transmitting upstream. The length of the ECC field may be selected to provide a level of performance for a particular function (e.g., for a dashboard display as compared to a non-critical infotainment display unit for viewing by a rear seat passenger).

The field 214 contains information that helps identify the display to which the received packet is to be routed. The number of bits in field 214 is sufficient to uniquely identify a particular stream (e.g., video channel) and/or display (e.g., at least one display for consuming and playing back the stream associated with the received packet). In a first example: field 214 includes sufficient bits to identify a particular stream (e.g., a channel number), where the splitter is programmed (e.g., via configuration commands described herein) to route received packets to at least one display (e.g., set to the channel number so that more than one display can play back the same stream). In a second example: the field 214 contains enough bits to identify the particular display (e.g., dashboard or electronic side view "mirror" display) on which the particular received packet is to be displayed. In a third example: the field 214 contains sufficient bits to indicate a code for selecting a predefined routing configuration for consumption (e.g., routing to a local display) and/or forwarding a particular received packet. In a fourth example, field 214 includes enough bits to include a combination (e.g., some or all of the combinations) of the functions described herein for the first, second, and third examples.

The field 215 is reserved for transferring data for undefined (e.g., unpublished or unpublished) purposes. For example, the reserved field does not necessarily carry useful data in earlier systems, but can be used to communicate useful information in later systems, so that the packet length does not have to be changed to make room for carrying information that is implemented later. The field 215 may include enough bits to extendably transmit and receive packets having a common packet length (e.g., according to a subsequent protocol standard related to at least one existing FPD standard or according to a later developed proprietary protocol).

The field 216 indicates whether the packet is the last packet in the stream. In examples where field 216 indicates the last packet in the flow, the display that consumed the packet may take action in response to an indication that a particular received packet is the last packet in the flow. An example action (e.g., an action taken in response to an indication that a particular received packet is the last packet in a flow) may be a temporary action (e.g., a fast reversible action), such as dimming a display selected to display the flow associated with the particular received packet. Packet transmission and forwarding is described below with reference to fig. 4.

In a second example packet, such as packet 220, 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.

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

Field 223 includes an ECC code (e.g., for error detection and correction), such as the code included in field 213.

Field 224 is a field similar to field 214 and may include information to indicate which stream is associated with the packet and/or to indicate a display to which the packet is to be sent.

Field 225 is a field similar to field 215. Consecutive fields, such as field 216, need not be implemented in packets containing a stop field, as the presence of a stop field may be used to determine that the packet containing the stop field is the last packet in the stream. Using the stall field infers that the flow to be terminated releases space in the packet that would otherwise be used by the consecutive fields, the packet having the stall field to be reserved for potential future use (e.g., future use for any purpose).

Fig. 3 is a block diagram of an example multi-stream generator adapted to aggregate input streams in an example system adapted to selectively forward transmissions between serially linked devices. Multi-flow generator 300 is an example multi-flow generator that may be disposed on substrate 302. Multi-stream 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 a packetized video stream to a first stream splitter. The packetized video stream may be generated (e.g., sourced) from a video source (e.g., a digital camera) according to MIPI (mobile industry peripheral interface) Camera Serial Interface (CSI). The video source used to generate the example video 0-video 7 streams may include a sensor (e.g., sensor 402) that may include various cameras, such as a rear or side view camera, where each camera may be arranged to generate a respective video stream. The video source used to generate example video 0-video 7 streams may also include the head unit (e.g., head unit 401) itself, which may generate at least one video stream for display in response to a sensor, such as sensor 402 (as described below with respect to fig. 4).

In one example, a clock generator 304 is disposed on the substrate 302 and adapted to generate clock signals, such as a video pixel clock (VP clock), a video link layer clock (vclk _ link), a frame clock (clk _ frame), and a channel clock (clk _ div 40). In some examples, some clock signals may be generated by circuitry not included on the substrate 302. Furthermore, the architecture of the multi-stream generator is scalable (e.g., by a quadratic power) such that the multi-stream generator can aggregate a selected number (e.g., eight or more) of video streams (which can be addressed by including a sufficient number of bits in the field 214 and the field 224). In some examples, the receiver may include a transmitter such that information may be transmitted from the example receiver 310 (e.g., in a second, opposite direction). Multi-stream generator 300 may be adapted to transmit data bi-directionally (e.g., at 165 megabits per second upstream or 13 gigabits per second downstream), with examples of bi-directionally transmitting/receiving the transmitted data described in U.S. patent No. 9,363,067 entitled data signal transceiver circuitry for providing synchronous bi-directional communication over a common conductor pair issued on 6.7.2016, the entire contents of which are incorporated herein by reference.

For a first video stream (e.g., video input 0) in example multi-stream generator 300, pixel aligner 312 is adapted to sample the first video transmission to align (e.g., synchronize) the sampled data with an internal clock (e.g., VP clock) of multi-stream generator 300 and to generate horizontal synchronization (hsync) and vertical synchronization (vsync) information (e.g., to identify pixel locations of the received pixel data). The sampled data is validated by checking for errors (and correcting if possible) by a 32-bit Cyclic Redundancy Checker (CRC) 314. The authenticated information is stored in the video buffer 322 and is temporally associated with hsync and vsync information, such that, for example, start and stop packets may be associated with the start and end, respectively, of a video frame to be displayed. The video stream may be received (e.g., from a head unit) as a serial or parallel stream, accessed from a system memory (e.g., a frame memory), and/or transmitted/accessed by a combination thereof.

Stream mapper 330 is adapted to receive stream (e.g., video input stream 0) information and associated hsync and vsync signals from video buffer 322. In response to the video buffer 322 information and the 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 a value of an STRM field, such as field 214 or field 224).

The channel 0 link layer 332 is arranged to generate signals adapted, for example, to control physical layer parameters for transmitting data on channel 0 in accordance with a system protocol, such as the FPD protocol described below. The lane 1 link layer 334 is arranged to generate link control signals adapted, for example, to control physical layer parameters for transmitting data across lane 1 in accordance with a system protocol. The link control signal may be generated in synchronization with (e.g., in response to) the video link layer clock.

Packets from a particular stream (e.g., video input 0 stream) may be transmitted across either channel 0 or channel 1 in response to being allocated by transmit allocator (TX allocator) 342. The TX allocator 342 may allocate at least one transmit channel such that pixels of a video frame may be transmitted at a rate sufficient to meet the frame rate of the display indicated by the STRM field. A first output of TX allocator 342 is coupled to transmit lane 0 data to an input of framer 352 and a second output of TX allocator 342 is coupled to transmit lane 1 data to an input of framer 354. The pixels of the video frame may be transmitted in synchronization with the frame clock. In some examples, a particular channel may be associated with (e.g., as a system design choice) a respective display such that a video stream may be associated with (e.g., forwarded to) the respective display. In some examples, channels may be dynamically designated based on network traffic such that the channels may carry different video streams (e.g., where a stream splitter is adapted to associate received packets of a particular video stream with a particular display and, in response, forward/transmit packets of a given video stream toward the correct display).

Framer 352 and framer 354 are adapted to generate transmit frames according to a system protocol, such as a Low Voltage Differential Signaling (LVDS) protocol. The system protocol may be an LVDS standard such as a flat 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 "sublvds standard," current mode and/or voltage mode drivers/receivers, as well as other such low power, high speed signaling protocols (including gigabit multimedia serial link-GMSL). The FPD framer 362 is adapted to align data for transmission within a transmit frame, the FPD encoder 372 is adapted to encode the aligned data into symbols for transmission within the transmit frame, and the FPD frame physical aligner (FRAME PHY ALIGN)382 is adapted to buffer the encoded symbols for synchronous transmission by the transmitter 390 across channel 0 (e.g., as clocked by a channel clock). The FPD framer 364 is adapted to align data for transmission within a transmit frame, the FPD encoder 374 is adapted to encode the aligned data into symbols for transmission within the transmit frame, and the FPD frame physical aligner (FRAME PHY ALIGN)384 is adapted to buffer the encoded symbols for synchronous transmission across lane 1 by the transmitter 390. The encoded symbols may be decoded by a receiver, such as receiver 422, and encoded by a stream repeater, such as stream repeater 426 (e.g., a stream transmitter), for example, as described below.

For a second video stream (e.g., video input 7) in the example multi-stream generator 300, the pixel aligner 316 is adapted to sample the video transmission to align the sampled data with the internal clock of the multi-stream generator 300 and to generate horizontal synchronization (hsync) and vertical synchronization (vsync) information. The sampled data is verified by checking for errors by a 32-bit cyclic redundancy check code (CRC) 318. The authenticated information is stored in the video buffer 324 and is temporally associated with hsync and vsync information, such that, for example, start and stop packets may be associated with the start and end, respectively, of a video frame to be displayed.

The stream mapper 330 is adapted to receive stream (e.g., video input 7-stream) information and associated hsync and vsync signals from the video buffer 324. In response to the video buffer 324 information and the 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 a value of an STRM field, such as field 214 or field 224).

The lane 2 link layer 336 is arranged to generate signals adapted, for example, to control physical layer parameters for transmitting data on lane 2 in accordance with a system protocol. The lane 3 link layer 338 is arranged to generate signals adapted, for example, to control physical layer parameters for transmitting data across lane 3 in accordance with a system protocol.

Packets from a particular stream (e.g., video input 7 stream) may be transmitted across either lane 2 or lane 3 in response to being distributed by transmit distributor (TX distributor) 344. TX allocator 344 may allocate at least one transmit channel such that pixels may be transmitted at a rate sufficient to meet the frame rate of the display indicated by the STRM field. A first output of TX splitter 344 is coupled to transmit lane 2 data to an input of framer 356 and a second output of TX splitter 344 is coupled to transmit lane 1 data to an input of framer 358.

Framer 356 and framer 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 a fourth revision of the LVDS standard, such as the flat panel display link (FPD) protocol. The FPD framer 366 is adapted to align data for transmission within a transmission frame, the FPD encoder 376 is adapted to encode the aligned data into symbols for transmission within the transmission frame, and the FPD frame physical aligner (FRAME PHY ALIGN)386 is adapted to buffer the encoded symbols for synchronous transmission across lane 2 by the transmitter 390. 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 into symbols for transmission within the transmit frame, and the FPD frame physical aligner (FRAME PHY ALIGN)388 is adapted to buffer the encoded symbols for synchronous transmission across lane 3 by the transmitter 390.

Other video inputs (e.g., video input 2-video input 6) and channel outputs (e.g., channel 4-channel 15) and circuitry may be included such that the system bandwidth is sufficient to handle, for example, a large number of displays (e.g., instruments for passenger use, side and rear view, navigation and infotainment systems) and/or increased resolution. As described below with reference to fig. 4, an output (e.g., a multi-stream output) is coupled to at least one splitter for coupling a selected video stream to a respective local display. The local display need not be coupled to any splitter, but the cable requirements (e.g., number of connectors, cables, and/or conductors) in a system with multiple displays and video streams are increased for routing local displays that are not coupled to splitters.

Fig. 4 is a block diagram of an example system including at least one current divider adapted to selectively forward transmissions between serially linked devices. For example, system 400 is an example system that includes a head unit 401, a multi-stream generator 410, a splitter 420 (e.g., locally coupled to local display 404 via cable 405), a splitter 430 (e.g., locally coupled to local display 406 via cable 407), and a splitter 440 (e.g., locally coupled to local display 408 via cable 409). The splitters 420, 430, and 440 may be adapted to transmit data bi-directionally (e.g., at 165 megabits per second upstream or 13 gigabits per second downstream).

In an example, head unit 401 is coupled to receive sensor information from sensor 402. Sensor 402 may be a sensor suite associated with an electronic system of a vehicle (e.g., vehicle 110). Such sensors may include sensors adapted to sense the position of driver controls (e.g., shift levers, lights, steering wheels, turn signal levers, and other controls), vehicle properties (e.g., speed, natural gas content level, temperature, fuel flow, tire pressure, seat belts, and other properties), and positioning (e.g., radar, satellite navigation, cameras, aisle and curb sensors, and other relationship information). Head unit 401 is adapted to generate output information (e.g., video information) in response to the sensor information. Additional head units 401 may couple various sensors 402 and multi-stream generators 410.

The head unit 401 is adapted to generate video information for display on a local display 404 (which may be, for example, the CLUSTER 124), a local display 406 (which may be, for example, the heads-up display HUD 126), and a local display 408 (which may be, for example, the center meter display CID 128). For example, the head unit may generate: a first video stream of a vehicle dashboard in an operational state (e.g., for display on a display panel of a replacement mechanical gauge); a second video stream of the HUD (e.g., for displaying navigation information on a virtual screen on a windshield); and a third video stream of CIDs (e.g., for displaying real-time images from a rear-facing camera). For example, the header unit 401 is adapted to output the video streams as individual bitstreams.

The multi-stream generator 410 is a multi-stream generator, such as the multi-stream generator 300 described above. The multi-stream generator 410 is coupled to a video output (e.g., each of the video outputs) of the head unit 401 and is adapted to combine separate video streams (e.g., at least two video streams)) of the video streams received from the head unit 401 into a unified (e.g., multi-stream) video stream using a system protocol. The multi-stream generator is adapted to packetize information from the unified video stream (e.g., which includes information of at least two video streams) and transmit the unified video stream (multi-stream). Thus, the multi-stream generator is arranged as a source node of the unified video stream.

The individual packets (generated by the multi-stream generator) each include an identification field, such as an STRM identifier that can identify the selected display (e.g., the addressed display and/or the addressed node) as the destination of the packet. The multi-stream generator 410 is adapted to couple the encoded packets to a source output of the multi-stream generator 410 (e.g., a source output of a source node). A first cable (411) is connected between the multi-stream generator 410 (e.g., source node) and a first splitter (e.g., splitter 420). The first cable includes a conductor (and associated insulator/shield) sufficient to carry information for all channels (e.g., at least one channel) over which video information is transmitted.

The splitter 420 includes a local link controller 421, a stream input (e.g., 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 comprise a phy layer receiver, local exporter 425 may comprise a phy layer driver, and stream forwarder 426 may comprise a phy layer driver. The receiver 422 has a receiver output. The receiver 422 has a receiver input adapted to receive input data (e.g., a unified video stream) from an output of a source node (e.g., the multi-stream generator 410). The input data may be (and/or include) an incoming packet that includes an identification field, where the incoming packet 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., FPD protocol) different from the native protocol (e.g., eDP protocol described below).

Stream selector 423 includes a selector output. Stream selector 423 is coupled to a receiver output (e.g., an output of receiver 422), and stream selector 423 is configured to generate a destination indication at a selector output (e.g., an output of stream selector 423). For example, the stream selector 423 is adapted to monitor the receiver 422 for received transmissions of the STRM field contents (e.g., which may include functional data), such as the packets 210 and 220, and in response program the Demultiplexer (DEMUX) 424. In an example, flow selector 423 is adapted to generate the destination indication in response to the identification field (flow selector 423 optionally being adapted to receive the identification field).

Switch 427 includes a switch local output and a switch system output. Switch 427 is coupled to an output of receiver 422 (or optionally to an input of receiver 422) and is adapted to generate a transmission (e.g., an output signal) at a switch local output (e.g., a first output of the switch) in response to an indication of the flow selector 423 output and the input data, and is adapted to generate a transmission at a switch system output in response to the 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, the switch 427 is adapted to generate an output packet adapted to be transmitted at a switch local output (e.g., local exporter 425) in response to the identification field when, for example, the identification field indicates that the packet is to be exported to the local display 404. In one example, switch 427 is adapted to route incoming data to a switch system output (e.g., flow forwarder 426) in response to a destination indication when, for example, the destination indication at the output of flow selector 423 indicates that the packet is to be forwarded to another display (e.g., the packet is not being exported to local display 404). In another example, switch 427 forwards (e.g., transmits) all input data received by splitter 420, where the input data is coupled from receiver input 422 (where coupling may include coupling the input data through receiver 422 itself and the receiver 422 output), such that a transmission at the switch system output is generated by switch 427 in response to the input data (e.g., regardless of the stream field 214 and 224 contents).

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 the local display 404 via a local exporter 425. The first destination node is a local (e.g., local to the splitter 420 individual) node address that may be associated with at least one display node address. In an example, the demultiplexer 424 includes a second output adapted to be coupled to, for example, the local display 406 via the stream repeater 426, the cable 412, and the splitter 430. The second destination node is a non-local node address that may be associated with a display node address indicating a node address that is different from the node address associated with the first destination node. The node address may be a logical address of various display nodes, while the stream field content identifies a particular video stream (which may be selectively received, for example, by one or more displays having different logical addresses). The stream selector may be dynamically programmed (e.g., in response to received control packets) to direct the selected video stream to a local display associated with the stream selector. A stream forwarder 426 is coupled to the switch system output and is adapted to transmit according to the system protocol.

In an example, the demultiplexer 424 is adapted to couple incoming packets (e.g., through a switch) to a first output of the switch and a second output of the switch in response to a destination indication. In an example, the demultiplexer 424 is adapted to generate a packet at a selected one of at least a first output of the switch and a second output of the switch in response to the identification field. In an example, the demultiplexer 424 is adapted to generate a packet destination indication in response to an identification field of an incoming packet.

The local link controller is a local controller coupled to a switch local output, wherein the switch local output is adapted for transmission to a display. The local link controller 421 is adapted to monitor transmissions (e.g., packets 210 and 220) received by the receiver 422 for commands (e.g., functional data). The local link controller 421 is adapted to control the transmission of packets from the local outputs of the switch according to a local protocol (e.g., which is a different protocol than the system protocol).

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

The output of the local exporter 425 contains the local protocol. In an example, the native protocol is a displayport protocol, such as the video electronics association (VESA) embedded displayport (eDP) standard. Thus, the input data may be received by the receiver 422 according to a system protocol (e.g., FDP) different from the at least one native protocol. Other displayport protocols that may be supported as native protocols include: a Display Port (DP); an open liquid crystal display interface (OpenLDI); and Mobile Industry Processor Interface (MIPI) Display Serial Interface (DSI) and Camera Serial Interface (CSI). The first native protocol (e.g., 405) of the first display (e.g., 404) may be a different protocol than the second native protocol (e.g., 407) of the second display (e.g., 406).

The splitter 420 may be programmed to operate according to a protocol associated with a particular display locally coupled to the local exporter 425. For example, multi-stream generator 410 may configure splitter 420 by transmitting a start command to local link controller 421 that includes an indication of the selected protocol. For example, an indication of the selected protocol may be included in stream _ payload 212. In an example system, a first splitter (e.g., 420) is adapted to select a first native protocol (e.g., 405), and a second splitter (e.g., 430) is adapted to select a second native protocol that is a different protocol than the first native protocol.

In an example system with two displays, a first cable (e.g., 411) is coupled between the output of the multi-stream generator 410 and the input of the first shunt 420, and a second cable (e.g., 412) is coupled between a second output of the first shunt 420 and the input of the second shunt 430. In an example system with two displays, received packets (e.g., encoded packets) of a first video stream are transmitted across a first cable (e.g., via a first switch local output) to the first display, and received packets (e.g., encoded packets) of a second video stream are transmitted across the first cable and a second cable (e.g., via a first switch system output and a second switch local output) to the second display.

In an example with at least two displays, the shunt 430 may include: a second receiver having a second receiver output and having a second receiver input adapted to receive second input data from the first switch local output; a second selector having a second selector output, wherein the second selector is coupled to the second receiver, and wherein the second selector is 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, wherein the second switch is coupled to the second receiver, and wherein the second switch is adapted to generate a transmission at the second switch local output in response to the second selector output and an indication of the second input data, wherein the second switch is adapted to generate a transmission at the second switch system output in response to the second input data.

In an example system having at least two displays, the current splitter 430 may further include: comprising a second local controller coupled to the second switch local output, wherein the second switch local output is adapted for transmission to a second display, and wherein the second local exporter is arranged to transmit data to the second display in response to a start command including a second destination indication as a packet indicating the second display.

In another example system having at least two displays: the head unit is adapted to generate at least two video streams at an output of the head unit; and a multi-stream generator coupled to an output of the header unit and adapted to generate encoded packets including information from the at least two video streams and transmit the encoded packets to a source output, wherein the input data includes packets from one of the at least 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 the downstream splitter).

In an example system having at least two displays, the system includes: a head unit adapted to generate at least two video streams; a multi-stream generator coupled to the header unit and adapted to generate encoded packets and to couple the encoded packets to an output of the multi-stream generator, the encoded packets including identification fields and including information from at least two video streams; a first splitter having a first stream input coupled to the output of the multi-stream generator, the first splitter having a first output adapted to couple the received encoded packets to the first display according to the first native protocol in response to the identification field of the received encoded packets indicating the node address of the first display, and the first splitter having a second output adapted to forward the received encoded packets in response to the identification field of the received encoded packets indicating a different node address than the first display; and a second splitter having a second stream input coupled to the second output of the first splitter, the second splitter having a first output adapted to couple the received encoded packet to a second display according to a second native protocol in response to the identification field of the received encoded packet indicating a second display node, and the second splitter having 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 different from the second display node address. The example system may further include: a third splitter having a third stream input coupled to the second output of the second splitter, the third splitter having a first output adapted to couple the received encoded packet to a third display in response to the identification field of the received encoded packet indicating a third display node address, and the third splitter having 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 different from the third display node address. The example system may further include: a first cable coupled between the output of the multi-stream generator and the first stream input; and a second cable coupled between the second output of the first splitter and the second splitter, wherein the encoded packets of the first video stream are transmitted across the first cable to the first display, and wherein the encoded packets of the second video stream are transmitted across the first cable and the second cable to the second display. In an example system, the first native protocol may be a different protocol than the second native protocol.

An example method for network connecting multiple display systems may include operations such as: transmitting a first transmission including information of 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 including information of the received encoded packet in response to the identification field of the received encoded packet indicating a node address different from the first display node address; transmitting a third transmission including information of 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 including information of the received encoded packet in response to the identification field of the received encoded packet indicating a node address different from the second display node address. When the received encoded packet is a first encoded packet, the example method may further comprise: generating a first encoded packet in response to information received from a first video stream and a second encoded packet in response to information received from a second video stream; transmitting first encoded packets of a first video stream across a first cable to a first display; and transmitting second encoded packets of a second video stream across the first cable and the second cable to a second display. An example method may further comprise: the first video stream is generated in response to a sensor of a vehicle containing the first and second displays.

In an example system with three displays, a first cable (e.g., 411) is coupled between the output of the multi-current generator 410 and the input of the first shunt 420, a second cable (e.g., 412) is coupled between the second output of the first shunt 420 and the input of the second shunt 430, and a third cable (e.g., 413) is coupled between the second output of the second shunt 430 and the input of the third shunt 440. In an example system with three displays, received encoded packets of a first video stream are transmitted across a first cable (e.g., via a first switch local output) to a first display, and received encoded packets of a second video stream are transmitted across the first cable and a second cable (e.g., via a first switch system output and a second switch local output) to a second display, and received encoded packets of a third video stream are transmitted across the first cable, the second cable, and a third cable (e.g., via the first switch system output, the second switch system output, and a third switch local output) to a third display.

According to examples described herein, additional displays and video streams may be added to multiple display units without, for example, increasing the number of cables connected (e.g., physically connected) to head unit 401 and/or multi-stream generator 410.

Fig. 5 is a block diagram of an example system including at least one bus unit adapted to generate and forward a system wake-up signal between serially linked bus units. For example, system 500 is an example system that includes: a head unit 401 (e.g., coupled to the sensor 402), a first bus unit 510 (e.g., locally coupled to the head unit 401 via a local port 561 and a cable 560), a second bus unit 520 (e.g., locally coupled to the touch display 572 via a local port 562 and a cable 405), a third bus unit 530 (e.g., locally coupled to the touch display 573 via a local port 563 and a cable 407), and a fourth bus unit 540 (e.g., locally coupled to the touch display 574 via a local port 564 and a cable 409). The bus units 510, 520, 530, and 540 may be adapted to transfer data bi-directionally (e.g., at 165 megabits per second upstream or 13 gigabits per second downstream). The bus units 520, 530 and 540 may be serializers and/or deserializers (e.g., SERDES) and/or depolymers (e.g., 420, 430 and 440, respectively).

In an example wake-up sequence generally described later herein, the second bus unit 520 may be configured from a power-saving mode to an active mode (e.g., wake-up from a power-saving mode) by a local wake-up signal generated in response to a wake-up event detected at the touch display 572. In response to the local wake-up signal, the second bus unit 520 may generate and transmit a system wake-up signal to the first bus unit 510 (e.g., such that the system wake-up signal is transmitted in an upstream direction and in response wakes up the first bus unit 510). Similarly, the second bus unit 520 may generate and transmit a system wake-up signal to the third bus unit 530 (e.g., such that the system wake-up signal is transmitted in a downstream direction and the third bus unit 530 is woken up in response). In an example, the third bus unit 530, in response to receiving the system wake-up signal, may generate a subsequent wake-up signal and transmit the wake-up signal to the fourth bus unit 540 (e.g., such that the system wake-up signal is transmitted in a downstream direction and in response wakes up the third bus unit 530). Other wake-up sequences are described below (e.g., with respect to fig. 8, 9, and 10).

In a first example system, system 500 includes a First Bus Unit (FBU)510 having an FBU 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. FBU transceiver 512 is coupled to the FBU first system port, FBU local port and FBU wake-up input.

An FBU first system port (e.g., 591) is adapted to receive an FBU first system input signal. The FBU local port (e.g., 561) is adapted to receive an FBU local input signal. FBU transceiver 512 is configured to transmit data of an FBU first system input signal to an FBU local port (e.g., 561) in an FBU first mode (e.g., active mode). FBU transceiver 512 is configured to save power in the FBU second mode. FBU transceiver 512 is configured to enter FBU first mode in response to an FBU local wake-up signal. FBU transceiver 512 is configured to transmit an FBU system wake-up signal at one of an FBU first system port (e.g., 591) and an FBU local port (e.g., 561) in response to the FBU local wake-up signal.

FBU controller 514 has an FBU energy detection input and an FBU wake-up output 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.

FBU energy detector 516 has an FBU energy detection output coupled to an FBU energy detection input. FBU energy detector 516 is coupled to the FBU first system port (e.g., via bus 551) and the FBU local port (e.g., via node 561 a). 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 energy of one of the FBU first system input signal (e.g., via node 561a) and the FBU local input signal received by FBU transceiver 512 in the FBU second mode.

In the first example system, the system 500 further includes a Second Bus Unit (SBU)520 having an SBU first system port (e.g., upstream U port 582). The SBU first system port is coupled to the FBU first system port (e.g., downstream D-port 591). The SBU first system port (e.g., 582) is adapted to receive the FBU system wake-up signal, and the FBU first system port (e.g., 591) is adapted to receive the SBU system wake-up signal (e.g., if the SBU system wake-up signal is transmitted by SBU 520 via the SBU first system port).

SBU 520 may further include an SBU second system port (e.g., downstream D-port 592), an SBU local port (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 SBU first system port, the SBU second system port, the SBU local port, and the SBU wake-up input.

The SBU first system port (e.g., 582) is adapted to receive an SBU first system input signal, the SBU second system port (e.g., 592) is adapted to receive an SBU second system input signal, and the SBU local port (e.g., 562) is adapted to receive an SBU local input signal. SBU transceiver 522 is configured to transmit data of an SBU first system input signal to an SBU second system port (e.g., 592) in an SBU first mode (e.g., active mode), and SBU transceiver 522 is configured to save power in an SBU second mode (e.g., power save mode). The SBU transceiver 522 is configured to enter the SBU first mode in response to an SBU local wake-up signal. The SBU transceiver 522 is configured to transmit an SBU system wake-up signal at one of the SBU first system port and the SBU second system port in response to an SBU local wake-up signal.

In general, the SBU 520 may detect a wake-up signal at any of a first system port (e.g., 582), an SBU second system port (e.g., 592), and an SBU local port (e.g., 562). SBU 520 is configured to generate (in response to the detected wake-up signal) a subsequent wake-up signal to be transmitted to the port from which the detected wake-up signal was received. In a first scenario, the wake-up signal is detected via an SBU local port (e.g., 562), and in response, SBU transceiver 522 transmits a system wake-up signal via an SBU first system port (e.g., 582) and via an SBU second system port (e.g., 592). In a second scenario, the wake-up signal is detected via the SBU first system port (e.g., 582), and in response, SBU transceiver 522 transmits the system wake-up signal via the SBU second system port (e.g., 592) and the local wake-up signal via the SBU local port (e.g., 562). In a third scenario, the wake-up signal is detected via the SBU second system port (e.g., 592) and in response, SBU transceiver 522 transmits the system wake-up signal via the SBU first system port (e.g., 582) and the local wake-up signal via the SBU local port (e.g., 562). In response to SBU 522 receiving a system wake-up signal from one of FBU 510 or third bus unit 530, transmitting a local wake-up signal to touch display 572 may signal the touch display to transition from a power-saving mode to an active mode.

SBU controller 524 has an SBU energy detection input and an SBU wake-up output 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.

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

In the first example system, system 500 further includes a Third Bus Unit (TBU)530 having a TBU first system port (e.g., upstream U port 583), an optional TBU second 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 TBU first system port (e.g., 583) is coupled to the SBU second system port (e.g., 592). A TBU transceiver 532 is coupled to the TBU first system port, the optional TBU second system port, the TBU local port, and the TBU wake-up input.

A TBU first system port (e.g., 583) is adapted to receive a TBU first system input signal, an optional TBU second system port (e.g., 593) may be adapted to receive a TBU second system input signal, and a TBU local port (e.g., 563) is adapted to receive a TBU local input signal. The TBU transceiver 532 is configured to transfer data of the TBU first system input signal to one of a TBU local port (e.g., 563) and a TBU second system port (e.g., 593) in a TBU first mode (e.g., an active mode), and the TBU transceiver 532 is configured to conserve power in a TBU second mode (e.g., a power save mode). TBU transceiver 532 is configured to enter a TBU first mode in response to a TBU local wake-up signal. The TBU transceiver 532 is configured to transmit a TBU system wake-up signal at one of the TBU first system port and 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 a TBU system wake signal (e.g., transmitted by TBU 530 via the TBU first system port in response to the TBU system wake signal).

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

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

The TBU energy detector 536 has a TBU energy detection output coupled to the TBU energy detection input. 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). TBU energy detector 536 is configured to generate a TBU energy detection signal at the TBU energy detection output in response to TBU detection of energy of one of 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) received by TBU transceiver 532 in the TBU second mode.

In a first example system, system 500 may further include additional (e.g., optional) bus units for extending the serially linked system bus. For example, the fourth bus unit 540 has a first system port (e.g., upstream U-port 584), a second system port (e.g., downstream D-port 594), a local port (e.g., 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 TBU second system port (e.g., 593).

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. The transceiver 542 is configured to communicate data of a first system input signal to one of a local port (e.g., 564) and a second system port (e.g., 594) in a first mode (e.g., an active mode), and the transceiver 542 is configured to conserve power in a second mode (e.g., a power save mode). The transceiver 542 is configured to enter a first mode in response to a local wake-up signal. The 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 the local wake-up signal. The TBU second system port (e.g., 593) is adapted to receive a system wake-up signal generated by the fourth bus unit (e.g., transmitted by the fourth bus unit 540 via the fourth bus unit first system port in response to the fourth bus unit system wake-up signal).

The controller 544 has an energy detection input and a wake-up output 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.

The energy detector 546 has an energy detection output coupled to the 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 the energy detection output in response to detecting energy of one of the first system input signal (e.g., via node 584a), the optional second system input signal (e.g., via bus 554), and the local input signal (e.g., via node 564a) received by the transceiver 542 in the second mode.

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

For FBU 510, the UI devices (e.g., sensor 402 and head unit 401) include a UI port (e.g., 560) coupled to FBU local port (561), where the UI devices are adapted to receive user input (e.g., user touch, user voice, user manipulation, proximity detection, and physical or electronic indication). FBU 510 is configured to generate a user wake-up signal at the UI port in response to a user input. FBU 510 is configured to generate an SBU system wake-up signal in response to a 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.

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

For TBU 530, the UI device (e.g., touch display 573) includes a UI port (e.g., 407) coupled to TBU local port (563), where the UI device is adapted to receive user input. TBU 530 is configured to generate a user wake-up signal at the UI port in response to a user input. TBU 530 is configured to generate a TBU system wake-up signal in response to a 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 fourth bus unit local wake-up signal in response to the TBU system wake-up signal.

For the fourth bus unit 540, the UI device (e.g., touch display 574) includes a UI port (e.g., 409) coupled to the fourth bus unit local port (564), wherein 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 a 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 a fourth bus unit system wake-up signal, and any serially linked additional bus units are configured to generate respective unit local wake-up signals in response to system wake-up signals of adjacent serially linked bus units.

In a second example system, the system 500 includes a power management system 508. The power management system 508 includes a power manager, such as a PMIC (power manager integrated circuit) 518 coupled to the FBU 510, a PMIC 528 coupled to the SBU 520, a PMIC 538 coupled to the TBU 520, and a PMIC 548 coupled to the fourth bus unit 540. The PMIC 518, the PMIC 528, the PMIC 538, and the PMIC 548 may be included on a common substrate, may be included on a substrate including bus cells coupled with the respective PMICs, and/or combinations thereof. Power for operating controls such as a power manager and energy detection circuitry may be provided (e.g., coupled) via VDDKA (first power rail continuously active) power signals (e.g., which allows for reduced power consumption in power save mode).

In a second example system, system 500 includes circuitry (e.g., SBU 520) that includes a transceiver (e.g., 522), a controller (e.g., 524), and an energy detector (e.g., 526).

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

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

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

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

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

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

In further examples, the controller is further coupled to the first system port and the local port. 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. In an example, the controller may further comprise a data valid output, wherein the controller is configured to generate the data valid signal at the data valid output in response to detecting a wake-up pattern in one of the first system input signal and the local input signal. In an example, the energy detector may further include a data valid input and an enable power output, wherein the data valid input is coupled to the data valid output, and the energy detector is further configured to generate an enable power signal at the enable power output. In an example, the circuit may further include a power manager, wherein the power manager includes an enable power input and a power supply output, wherein the enable power input is 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 the enable power signal. In an example, the controller further comprises a power supply input, wherein 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. In an example system, the power manager of the circuit may further comprise a logic enable output and the controller may further comprise a logic enable input, wherein the logic enable input is coupled to the logic enable output, wherein the power manager may be further configured to generate a logic enable signal at the logic enable output in response to the power signal, and in response, the controller may generate the local wake-up signal further in response to the logic enable signal.

Fig. 6 is a flow diagram of an example method of wake-up signal publication for the example system of fig. 5. Example method 600 may include various techniques described below. In various embodiments, the operations described need not be performed in the order described. In the example method 600, the method may begin at 605.

At 605, the method may include receiving a first wake-up signal through a first port of a First Bus Unit (FBU). For example, the first wake-up signal may be generated by the head unit 401 in response to the sensor 502. The first wake-up signal may be received by FBU 510 at local port 561. The method may continue at 610.

At 610, the method may include applying power to a second port of the FBU in response to the first wake-up signal. For example, power management circuitry such as PMIC 518 may couple operating power to a transmitter (e.g., of transceiver 512) such that the transmitter may exit a power saving mode and enter an active mode (e.g., where a signal may be transmitted). In an example, power may be coupled by energizing a power source. In another example, a system clock is activated (e.g., published) such that additional power is drawn in response to the system clock switching being activated in response to switching of active CMOS circuitry. In an embodiment, the entire bus unit may be placed in an active mode by applying power to all bus unit active circuitry in response to a received wake-up signal. The method may continue at 615.

At 615, the method may include transmitting a second wake-up signal through a second port of the FBU in response to the first wake-up signal. For example, the transmitter portion of the transceiver 512 may transmit a second wake-up signal from a second port (e.g., the first system port 591). The method may continue at 620.

At 620, the method may include receiving a second wake up signal through 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 the SBU 520 at the first system port 582. The method may continue at 625.

At 625, the method may include applying power to a second port of the SBU in response to the second wake-up signal. For example, power management circuitry such as PMIC 528 may couple operating power to a transmitter (e.g., of transceiver 522) such that the transmitter may exit a power saving mode and enter an active mode (e.g., where a signal may be transmitted). The method may continue at 630.

At 630, the method may include transmitting, by the second port of the SBU, a third wake-up signal in response to the 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., second system port 592). The transmitter portion of the transceiver 522 may optionally send a local wake-up signal from a third port (e.g., 562) to a locally coupled device (e.g., touch display 572) in response to the second wake-up signal. The method may continue at 635.

At 635, the method may include receiving a third wake up signal through a first port of a Third Bus Unit (TBU). For example, the third wake-up signal may be generated by the SBU 520 in response to the second wake-up signal. The third wake-up signal may be received by the TBU 530 at the first system port 582. The method may continue at 625.

At 640, the method may include applying power to the TBU in response to the third wake-up signal. For example, power management circuitry such as PMIC 538 may couple operating power to TBU 530 such that TBU 530 may exit a power saving mode and enter an active mode (e.g., where signals may be actively received and transmitted). Thus, a local wake event may be published across and via the serial chain of bus units in the system 500 described herein.

Fig. 7 is a flow diagram of an example method wake-up signal detection and wake-up signal processing of the example system of fig. 5. Example method 700 may include various techniques described below. In various embodiments, the operations described need not be performed in the order described. In the example method 700, the method may begin at 705.

At 705, the method may include monitoring, by an energy detector (e.g., 526), for an awake mode signal. For example, the wake mode signal may be a VDDKA signal, which may supply operating power to an energy detector of the bus unit. The method may continue at 710.

At 710, if the wake mode signal is asserted, the method continues at 715; if not, the method continues at 705.

At 715, the method may include monitoring, by an energy detector (e.g., 526), the input signal for signal energy. For example, an energy detector of a bus unit may compare a field strength, current, and/or voltage level carried by an electrical conductor to a threshold to detect a quantitative change in an input signal. The signal line network (e.g., signal line) may be a dedicated wake-up signal conductor, or may be used for other purposes (e.g., a signal channel for receiving video stream information from an upstream source), while the bus unit operates in an active mode. The method continues at 720.

At 720, if signal energy is detected, the method continues at 725; if no signal energy is detected, the method continues at 705.

At 725, the method may include asserting, by an energy detector (e.g., 526), an enable power signal in response to detecting the signal energy. The method continues at 730.

At 730, the method may include asserting, by an energy detector (e.g., 526), an energy detection signal in response to detecting the signal energy. The method continues at 735.

At 735, the method may include applying power to a controller (e.g., 524) of the bus unit through a power management interface controller (e.g., 528) in response to the asserted enable power signal. The method continues at 740.

At 740, the method may include asserting, by the power management interface controller (e.g., 528), a logic enable signal in response to the enable power signal. For example, the logic enable signal may be asserted after a duration that the logic circuit of the controller may be stable after applying power. The method continues at 745.

At 745, the method can include determining, by the controller (e.g., 524), a start time of the valid detection period. For example, the controller may determine a start time (e.g., start timer) for a valid detection period during which the input signal (e.g., potential wake-up signal) is evaluated for valid data (e.g., wake-up pattern) in response to the logic enable signal. The method continues at 750.

At 750, the method may include evaluating, by a controller (e.g., 524) of the bus unit, the received signal of the input signal for valid data. For example, the input signal may be evaluated to determine the presence of an awake mode. The valid data may also include a wake-up code configured to identify a bus unit from which to receive a wake-up signal in the input signal. The wake-up pattern may be encoded to reduce entropy values (e.g., to reduce false positives generated by injected noise). The method continues at 755.

At 755, if valid data is detected, the method continues at 780; if valid data is not detected, the method continues at 760.

At 760, if the valid detection period has expired (e.g., exceeded), then the method continues at 765; if the valid detection period has not expired, the method continues at 750.

At 765, the method can include indicating, by a controller (e.g., 524) of the bus unit, that valid data was not detected. The method continues at 770.

At 770, the method may include de-asserting, by an energy detector (e.g., 526), the enable power signal in response to an indication that valid data is not detected. For example, the power signal may be de-asserted enabled by negating an active low signal (e.g., valid data) that, when active low, indicates that valid data has been detected. The method continues at 775.

At 775, the method may include shutting off power from a controller (e.g., 524) of the bus unit through a power management interface controller (e.g., 528) in response to the de-asserted enable power signal. The method continues at 705.

At 780, the method may include transmitting, by a bus unit (e.g., bus unit 520 being a first bus unit including energy detector 526 and controller 524), 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 the second bus unit, wherein the second wake-up signal is encoded with an identifier of the first bus unit, and wherein the second bus unit is not the bus unit that sent the first wake-up signal. The wake-up signal may include a repeating pattern such that the wake-up signal may be transmitted (e.g., repeatedly transmitted) during an active detection period. The length (e.g., duration) of the active detection period may be selected for the respective bus unit. In an example, the wake pattern includes three start bits "101", four address bits "0010" (which indicate the bus unit 520), and an even parity bit "1", such that the transmitted wake pattern is a repeatable pattern of eight bits "10100101". When the received pattern does not include the correct parity bit and does not include the start bit "101," the controller 524 deasserts the data valid signal (e.g., sets it high) to indicate that the received wake pattern is invalid, such that the energy detector 526 does not assert the enable power signal in response to the invalid wake pattern.

FIG. 8 is a block diagram of a first example wake-up signal processing scenario in an example system. In an example, system 800 includes serially linked bus units such as 810, 820, 830, and 840. The bus units may be deserializers (which may include both serializing circuits and deserializing circuits themselves) and/or depacketizers (described above with respect to fig. 4).

FBU 810 may be similar to multi-stream generator 410 and/or FBU 510. FBU 810 may be locally coupled to various devices (e.g., sensor 402 and head unit 401) that may generate local wake-up signals in response to inputs generated by any coupled sensors. The FBU 810 is upstream (e.g., relative to the direction of flow of most of the video stream in the system bus main channel) of the SBU 820. FBU 810 is coupled to SBU 820 via cable 801. Cable 801 (and each of cables 802, 803, and 804) may be a cable bundle that includes conductors (e.g., twisted pair, coaxial cable, or optical fiber) for sending and/or receiving a wake-up signal. In some examples, conductors reserved in the form of "channels" for video streaming in the active mode may be used to transmit a wake-up signal to a neighboring bus unit in a power saving mode.

FBU 810 is coupled to a Second Bus Unit (SBU)820 via cable 801. SBU 820 is locally coupled to touch display 826 (which may be similar to touch display 572) via cable 824, where SBU 820 is configured to de-aggregate the video (through switch 822) and send the de-aggregated stream to touch display 826 in active mode. SBU 820 is coupled to a Third Bus Unit (TBU)830 via cable 802. TBU 830 is locally coupled to touch display 836 (which may be similar to touch display 573) via cable 834, where TBU 830 is configured to de-aggregate video (through switch 832) and send the de-aggregated stream to touch display 836 in active mode. TBU 830 is coupled to a fourth bus unit 840 via cable 803. Fourth bus unit 840 is locally coupled to touch display 846 (which may be similar to touch display 574) via cable 844, where fourth bus unit 840 is configured to disaggregate video (through switch 842) and send the disaggregated stream to touch display 846 in an active mode. The fourth bus unit 840 may be coupled to an adjacent (e.g., downstream) bus unit via a cable 804 (where even more downstream bus units may be serially linked along the system bus, where each of the additional downstream units may be locally coupled with similar circuitry).

In a first example scenario, a first bus unit (e.g., FBU 810) 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). A system wake-up signal 850 is generated at a first output (e.g., cable 801). The second bus unit (e.g., SBU 820) is configured to generate (e.g., transmit) a system wake-up signal 851 at a second time (e.g., time T1 after the first time) in response to the system wake-up signal 850. A system wake-up signal 851 is generated at a second output (e.g., cable 802). The third bus unit (e.g., TBU 830) is configured to generate (e.g., transmit) a system wake-up signal 852 at a third time (e.g., time T2 after the second time) in response to the system wake-up signal 851. A system wake-up signal 852 is generated at a third output (e.g., cable 803). The fourth bus unit (e.g., fourth bus unit 840) is configured to generate (e.g., transmit) the system wake signal 853 at a fourth time (e.g., time T3 after the third time) in response to the system wake signal 852. A system wake-up signal 853 is generated at a fourth output (e.g., cable 804).

FIG. 9 is a block diagram of a second example wake-up signal processing scenario in an example system. In an example, system 900 includes serially linked bus units such as 910, 920, 930, and 940. The bus units may be deserializers and/or depolymers.

The FBU 910 may be similar to the multi-stream generator 410 and/or the FBU 510. FBU 910 may be locally coupled to various devices (e.g., sensor 402 and head unit 401) that may generate local wake-up signals in response to inputs generated by any coupled sensors. The FBU 910 is upstream of the SBU 920. The FBU 910 is coupled to the SBU 920 via a cable 901. Cable 901 (and each of cables 902, 903, and 904) may be a cable bundle that includes conductors for sending and/or receiving a wake-up signal. In some examples, conductors reserved in the form of "channels" for video streaming in the active mode may be used to transmit a wake-up signal to a neighboring bus unit in a power saving mode.

FBU 910 is coupled to a Second Bus Unit (SBU)920 via cable 901. The SBU 920 is locally coupled to a touch display 926 (which may be similar to the touch display 572) via a cable 924, wherein the SBU 920 is configured to disaggregate the video (through switch 922) and send the disaggregated stream to the touch display 926 in an active mode. SBU 920 is coupled to a Third Bus Unit (TBU)930 via cable 902. TBU 930 is locally coupled to touch display 936 (which may be similar to touch display 573) via cable 934, where TBU 930 is configured to de-aggregate the video (through switch 932) and send the de-aggregated stream to touch display 936 in an active mode. TBU 930 is coupled to a fourth bus unit 940 via cable 903. The fourth bus unit 940 is locally coupled to a touch display 946 (which may be similar to the touch display 574) via a cable 944, wherein the fourth bus unit 940 is configured to de-aggregate the video (through a switch 942) and send the de-aggregated stream to the touch display 946 in the active mode. The fourth bus unit 940 may be coupled to an adjacent (e.g., downstream) bus unit via a cable 904 (where even more downstream bus units may be serially linked along the system bus, where each of the additional downstream units may be locally coupled with similar circuitry).

In a second example 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 touch display 926). A 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 touch display 926). A system wake-up signal 951 is generated at a second output (e.g., cable 902). The second bus unit (e.g., TBU 930) is configured to generate (e.g., transmit) a system wake-up signal 952 at a second time (e.g., time T1 after the first time) in response to the system wake-up signal 951. A system wake-up signal 952 is generated at a third output (e.g., cable 903). The third bus unit (e.g., fourth bus unit 940) is configured to generate (e.g., transmit) a system wake-up signal 953 at a third time (e.g., time T2 after the second time) in response to the system wake-up signal 952. A system wake-up signal 953 is generated at a fourth output (e.g., cable 904).

FIG. 10 is a block diagram of a third example wake-up signal processing scenario in an example system. In an example, system 1000 includes serially linked bus units such as 1010, 1020, 1030, and 1040. The bus units may be deserializers and/or depolymers.

FBU 1010 may be similar to multi-stream generator 410 and/or FBU 510. FBU 1010 may be locally coupled to various devices (e.g., sensor 402 and head unit 401) that may generate local wake-up signals in response to inputs generated by any coupled sensors. FBU 1010 is upstream of SBU 1020. FBU 1010 is coupled to SBU 1020 via cable 1001. Cable 1001 (and each of cables 1002, 1003, and 1004) may be a cable bundle that includes conductors for sending and/or receiving a wake-up signal. In some examples, conductors reserved in the form of "channels" for video streaming in the active mode may be used to transmit a wake-up signal to a neighboring bus unit in a power saving mode.

FBU 1010 is coupled to a Second Bus Unit (SBU)1020 via a cable 1001. SBU 1020 is locally coupled to touch display 1026 (which may be similar to touch display 572) via cable 1024, where SBU 1020 is configured to de-aggregate the video (through switch 1022) and send the de-aggregated stream to touch display 1026 in the active mode. SBU 1020 is coupled to a Third Bus Unit (TBU)1030 via cable 1002. TBU 1030 is locally coupled to touch display 1036 (which may be similar to touch display 573) via cable 1034, where TBU 1030 is configured to de-aggregate the video (through switch 1032) and send the de-aggregated stream to touch display 1036 in the active mode. TBU 1030 is coupled to 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 the touch display 574) via a cable 1044, where the fourth bus unit 1040 is configured to disaggregate the video (through the switch 1042) and send the disaggregated stream to the touch display 1046 in the active mode. The fourth bus unit 1040 can be coupled to an adjacent (e.g., downstream) bus unit via a cable 1004 (where even more downstream bus units can be serially linked along the system bus, where each of the additional downstream units can be locally coupled with similar circuitry).

In a third example 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 touch display 1036). A 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 touch display 1036). A system wake-up signal 1051 is generated at a second output (e.g., cable 1003). The second bus unit (e.g., TBU 1020) is configured to generate (e.g., transmit) a system wake-up signal 1052 at a second time (e.g., time T1 after the first time) in response to the system wake-up signal 1050. A system wake-up signal 1052 is generated at a third output (e.g., cable 1001). The third bus unit (e.g., fourth bus unit 1040) is configured to generate (e.g., transmit) a system wake-up signal 1053 at a second time (e.g., time T1 after the first time) in response to the system wake-up signal 1051. A system wake-up signal 1053 is generated at a fourth output (e.g., cable 1004).

Fig. 11 is a block diagram of another example system including at least one current divider adapted to selectively forward transmissions between serially linked devices. For example, system 1100 is an example system that includes a source 1101, a serializer 1110 (coupled to source 1101 via cable 1102), a deserializer 1120 (e.g., locally coupled to local display 1104 via cable 1105), a deserializer 1130 (e.g., locally coupled to local display 1106 via cable 1107) and a deserializer 1140 (e.g., locally coupled to local display 1108 via cable 1109).

Cables 1111, 1112, and 1113 each include the physical media through which the system protocol (e.g., system bus) is implemented. The system protocol may be unidirectional or bidirectional. In an embodiment of the two-way system protocol: establishing a first bidirectional serial link between the serializer 1110 and the deserializer 1120 across a cable 1111 (the cable is coupled between the serializer 1110 and the deserializer 1120); establishing a second bidirectional serial link between deserializer 1120 and deserializer 1130 across cable 1112 (the cable coupled between deserializer 1120 and deserializer 1130); and establishing a third bidirectional serial link between deserializer 1130 and deserializer 1140 across cable 1113 (the cable coupled between deserializer 1130 and deserializer 1140).

The bidirectional serial link may be asymmetric or symmetric. An example asymmetric bidirectional link includes an upstream speed of 165 megabits per second (e.g., for bit traffic toward the serializer 1110) and a downstream speed of 13 gigabits per second (e.g., for bit traffic away from the serializer 1110). The asymmetric speed allows high-resolution video to be transmitted downstream at high bit rates (e.g., for transmitting various high-resolution video streams to a selected display) while still allowing a robust bi-directional system control and communication link between devices. Example asymmetric bidirectional links include symmetric data speeds such that data can be transmitted at full rate in either direction.

In the example, source 1101 is a source such as head unit 401. Source 1101 is coupled to serializer 1110 via cable 1102. Cable 1102 is arranged to carry at least one video stream in accordance with a protocol such as MIPI CIS.

In an example, the serializer 1110 is a serializer such as the multi-stream generator 410. Serializer 1110 includes a transmitter 1190, such as transmitter 390, adapted to transmit a multi-stream (e.g., generated by serializer 1110 and including reformatted information of at least one video stream carried across cable 1102) such that deserializer 1120 may receive and process (e.g., process a portion of) the transmitted multi-stream.

In an example, deserializer 1120 is a deserializer such as splitter 420. Deserializer 1120 is coupled to serializer 1110 via cable 1111. Deserializer 1120 includes a receiver 1122 (e.g., receiver 422) arranged to receive information transmitted by a transmitter 1190. The deserializer 1120 includes a transmitter 1126 (e.g., stream forwarder 426) arranged to transmit information received from the transmitter 1190. Cable 1111 is arranged to carry the multi-stream output transmitted by transmitter 1190 according to a protocol such as FPD link IV. Deserializer 1120 is locally coupled to local display 1104 (e.g., local display 404) via cable 1105. The cable 1105 is arranged to carry the selected video stream in accordance with a protocol such as eDP (extended display protocol).

In an example, deserializer 1130 is a deserializer such as splitter 430. The deserializer 1130 is coupled to the serializer 1120 via a cable 1112. Deserializer 1130 includes a receiver 1132 (e.g., receiver 422) arranged to receive information transmitted by transmitter 1126. Deserializer 1130 includes a transmitter 1136 (e.g., stream forwarder 426) arranged to transmit information received from transmitter 1126. Cable 1112 is arranged to carry the multi-stream output transmitted by transmitter 1126 in accordance with a protocol such as FPD link IV. Deserializer 1130 is locally coupled to local display 1106 (e.g., local display 406) via cable 1107. Cable 1107 is arranged to carry a selected video stream according to a protocol such as eDP.

In an example, deserializer 1140 is a deserializer such as splitter 440. The deserializer 1140 is coupled to the serializer 1130 via the cable 1113. Deserializer 1140 includes a receiver 1142 (e.g., receiver 422) arranged to receive information transmitted by a transmitter 1136. Deserializer 1140 optionally includes a transmitter 1146 (e.g., stream repeater 426) arranged to transmit information received from transmitter 1136. The cable 1113 is arranged to carry the multi-stream output transmitted by the transmitter 1136 according to a protocol such as FPD link IV. Deserializer 1140 is locally coupled to local display 1108 (e.g., local display 408) via cable 1109. The cable 1109 is arranged to carry selected video streams in accordance with a protocol such as eDP.

For example, when the last deserializer in the chain receives only data intended (e.g., addressed) for display on a respective local display locally coupled to the last deserializer, the last deserializer need not include a switch such as switch 427.

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