MOST(Media Oriented System Transport)網路之影音伺服器設計

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(2). . . MOST (Media Oriented System Transport) . . . . . . Design of Audio/Video Server under MOST (Media Oriented System Transport) Network . .

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(5) MOST (Media Oriented System Transport) . Design of Audio/Video Server under MOST (Media Oriented System Transport) Network . . .

(6). . . Studen Jun-Ying Huang . .

(7). AdvisorChi-Hsu Wang. . . . . . . . . . . . !" . A Thesis Submitted to Department of Electrical and Control Engineering College of Electrical Engineering and Computer Science National Chiao-Tung University In Partial Fulfillment of the Requirements for the Degree of Master in Electrical and Control Engineering September 2007 Hsinchu, Taiwan, Republic of China . .

(8) MOST (Media Oriented System Transport) . . . . . . . . . . . . .

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(13) Design of Audio/Video Server under MOST (Media Oriented System Transport) Network Student Jun-Ying Huang. Advisor Chi-Hsu Wang. Department of Electrical and Control Engineering National Chiao Tung University. ABSTRACT The main purpose of this thesis is to explore and demonstrate the versatile multimedia applications under MOST (Media Oriented System Transport) network which is originally developed for the automotive industry. With the MOST NetServices API and an example application provided by OASIS SiliconSystems (which is now part of SMSC), we can build our programs to control multimedia devices for MOST, such the DVD Player, Video Decoder, Radio Tuner and Audio Amplifier are installed in our MOST network. Besides, both the MOST PCI Board and the Optolyzer Interface Box are used for establishing the communication between the MOST network and a PC which serves as a control central for the MOST network. The details of understanding the NetServices API are explained through different multimedia applications. In addition to the ordinary MOST applications, a new Audio/Video server under MOST network is also designed.. ii.

(14) ACKNOWLEDGEMENT My deepest gratitude goes first and foremost to my advisor, Prof. Chi-Hsu Wang, for his constant encouragement and guidance. Without his illuminating instruction, this thesis could not have reached its present form. Secondly, I would like to thank my senior, Jian-Xun Wu, and Support Team from SMSC Automotive Infotainment Systems, for their instructions in my research. Besides, I am grateful to everyone in our ECL Lab. With their companion, I always have a good time during these days in NCTU. Finally I would like to express my sincere gratitude to my family for the loving considerations and great confidence in me.. iii.

(15) TABLE OF CONTENTS ¤. ..................................................................................................................................i. ABSTRACT.......................................................................................................................... ii ACKNOWLEDGEMENT .................................................................................................... iii TABLE OF CONTENTS.......................................................................................................iv LIST OF TABLES.............................................................................................................. viii LIST OF FIGURES................................................................................................................x CHAPTER 1 Introduction ......................................................................................................1 1.1 MOST Technology....................................................................................................1 1.2 Scope of work...........................................................................................................2 1.3 Structure of the Thesis...............................................................................................2 CHAPTER 2 MOST Specification..........................................................................................4 2.1 MOST Topology .......................................................................................................5 2.1.1 Point to Point Link .........................................................................................5 2.1.2 Ring Topology................................................................................................5 2.1.2.1 Rings Incorporating Splitters................................................................7 2.1.2.2 Star of Rings ........................................................................................7 2.2 Data Transport ..........................................................................................................8 2.2.1 Data Types .....................................................................................................8 2.2.2 Frame Structure..............................................................................................9 2.2.2.1 Blocks .................................................................................................9 2.2.2.2 Frames...............................................................................................10 2.2.3 Transparent Channel.....................................................................................11 2.3 Logical Device Model.............................................................................................11 2.3.1 Function Block .....................................................................................12 2.3.1.1 NetBlock ...........................................................................................13 2.3.1.2 Functions ...........................................................................................13 2.3.1.3 Function Interfaces ............................................................................15 2.3.2 NetServices ..................................................................................................16 2.3.3 MOST Transceiver and its Internal Services..........................................16 2.3.3.1 Bypass ...............................................................................................17 2.3.3.2 Timing Master ...................................................................................18 2.3.3.3 Addressing.........................................................................................18 2.3.3.4 Channel administration ......................................................................19 2.3.3.5 Power Management ...........................................................................20 2.3.4 Physical Interface .........................................................................................20 iv.

(16) 2.4 Protocols.................................................................................................................21 2.4.1 Structure of MOST Protocols .......................................................................21 2.4.1.1 DeviceID ...........................................................................................21 2.4.1.2 FBlockID...........................................................................................21 2.4.1.3 InstID ................................................................................................23 2.4.1.4 FktID.................................................................................................23 2.4.1.5 OPType..............................................................................................24 2.4.1.6 Length ...............................................................................................24 2.4.1.7 Data...................................................................................................25 2.4.2 Communication on Application Level...........................................................25 CHAPTER 3 MOST NetServices .........................................................................................26 3.1 System Services Overview......................................................................................26 3.1.1 Application Socket .......................................................................................27 3.1.1.1 MOST Command Interpreter .............................................................28 3.1.1.2 NetBlock ...........................................................................................28 3.1.1.3 Network Master Shadow....................................................................28 3.1.1.4 Address Handler, De-Central Device Registry....................................28 3.1.1.5 MOST Supervisor Layer II ................................................................29 3.1.1.6 Notification Service ...........................................................................29 3.1.2 Basic Layer System Services ........................................................................29 3.1.2.1 MOST Supervisor ..............................................................................29 3.1.2.2 Low Level Driver ..............................................................................30 3.1.2.3 Control Message Service ...................................................................30 3.1.2.4 Synchronous Channel Allocation Service...........................................30 3.1.2.5 Transparent Channel Allocation Service.............................................31 3.1.2.6 Asynchronous Data Transmission Service ..........................................31 3.1.2.7 Transceiver Control Service ...............................................................31 3.1.3 Low Level System Services..........................................................................31 3.1.3.1 Physical Interface...............................................................................32 3.1.3.2 Physical Layer ...................................................................................32 3.1.3.3 Low Level Bus Management .............................................................32 3.1.3.4 Packet Logic ......................................................................................32 3.1.3.5 Communication Management ............................................................32 3.1.3.6 Transaction Level ..............................................................................32 3.1.3.7 Real Time Transceiver .......................................................................32 3.1.3.8 Format Converter...............................................................................33 3.1.4 Stream Services ....................................................................................33 3.2 NetServices Layer 1 API .........................................................................................33 3.2.1 MOST NetServices Kernel (MNS) ...............................................................34 v.

(17) 3.2.2 MOST Supervisory and Startup Functions (MSV) ........................................34 3.2.3 Control Message Service (CMS) ..................................................................35 3.2.4 Application Message Service (AMS) ............................................................35 3.2.5 Remote Control Service (RCS).....................................................................36 3.2.6 Synchronous Channel Allocation Service (SCS) ...........................................36 3.2.7 Transparent Channel Allocation Service (TCS).............................................37 3.2.8 Asynchronous Data Transmission Service (ADS) .........................................37 3.2.9 MOST Transceiver Control Service (MCS) ..................................................38 CHAPTER 4 Multimedia Applications .................................................................................39 4.1 Hardware Overview ................................................................................................39 4.1.1 RadioTuner4MOST ......................................................................................40 4.1.2 Amplifier4MOST .........................................................................................40 4.1.3 DVDPlayer4MOST ......................................................................................41 4.1.4 VideoDecoder4MOST ..................................................................................41 4.1.5 MOST PCI Board.........................................................................................42 4.1.6 Optolyzer Interface Box ...............................................................................42 4.2 Software Utilities ....................................................................................................43 4.2.1 MOST Interface Control...............................................................................43 4.2.1.1 Device Mode .....................................................................................43 4.2.1.2 MOST Edit ........................................................................................44 4.2.2 MOST Radar ................................................................................................45 4.2.2.1 Main Window and Node Symbol .......................................................46 4.2.2.2 Property Window...............................................................................47 4.2.3 GraphEdit.....................................................................................................52 4.3 Multimedia Control Program ..................................................................................53 4.3.1 NetServices Layer 1 Example (NSL1_EX) ...................................................54 4.3.1.1 AMS ..................................................................................................56 4.3.1.2 CMS ..................................................................................................58 4.3.1.3 RCS...................................................................................................60 4.3.2 Enhancement of the Program........................................................................63 4.3.2.1 Radio Tuner .......................................................................................64 4.3.2.2 DVD Player .......................................................................................66 4.3.2.3 Video Decoder ...................................................................................69 4.3.2.4 Amplifier ...........................................................................................71 4.3.2.5 MOST PCI Board ..............................................................................73 4.4 Multimedia Applications (Step-by-Step Instructions) ..............................................75 4.4.1 Application 1: Listen to the Radio.................................................................76 4.4.2 Application 2: Watch DVD movies...............................................................77 4.4.3 Application 3: Watch DVD movies (with Video Decoder) ............................79 vi.

(18) 4.4.4 Application 4: The MOST PCI Board as a Sound Card .................................81 4.4.5 Application 5: Audio Streams be captured and played on PC ........................84 4.4.6 Application 6: MPEG-2 Streams be captured and played on PC....................87 4.4.7 Application 7: A/V Server under MOST Network.........................................90 CHAPTER 5 Audio/Video Server under MOST Network .....................................................91 5.1 The Idea and Design ...............................................................................................91 5.1.1 VideoDecoder4MOST ..................................................................................91 5.1.2 MOST PCI Board.........................................................................................92 5.1.3 Applicable File Types ...................................................................................93 5.2 Implementation.......................................................................................................94 5.2.1 The User Interface ........................................................................................94 5.2.2 Step-by-Step Instructions..............................................................................96 5.3 Result and Discussion ...........................................................................................102 CHAPTER 6 Conclusion....................................................................................................105 REFERENCES...................................................................................................................106. vii.

(19) LIST OF TABLES Table 2.1 Table 2.2 Table 2.3 Table 2.4 Table 2.5 Table 2.6 Table 2.7 Table 2.8 Table 4.1 Table 4.2 Table 4.3. Speed requirements of different applications........................................................8 Structure of MOST Frame..................................................................................10 Messages for Methods .......................................................................................14 Messages for Properties .....................................................................................14 Addressing modes vs. Address range .................................................................19 FBlockIDs .........................................................................................................22 Responsibilities for FBlockID and FktID ranges ................................................23 OPTypes for properties and methods..................................................................24 Node Symbol Description..................................................................................47 Type of message to be sent via CMS ..................................................................59 Protocol Mapping of RadioTuner4MOST Control Program ...............................65. Table 4.4 Protocol Mapping of DVDPlayer4MOST Control Program................................67 Table 4.5 Protocol Mapping of DVDPlayer4MOST Control Program (continued).............68 Table 4.6 Protocol Mapping of VideoDecoder4MOST Control Program............................70 Table 4.7 Protocol Mapping of Amplifier4MOST Control Program...................................72 Table 4.8 Instructions for Application 1, 1 of 2..................................................................76 Table 4.9 Instructions for Application 1, 2 of 2..................................................................77 Table 4.10 Instructions for Application 2, 1 of 2................................................................78 Table 4.11 Instructions for Application 2, 2 of 2 ................................................................79 Table 4.12 Instructions for Application 3, 1 of 2................................................................80 Table 4.13 Instructions for Application 3, 2 of 2................................................................81 Table 4.14 Instructions for Application 4, 1 of 3................................................................82 Table 4.15 Instructions for Application 4, 2 of 3................................................................83 Table 4.16 Instructions for Application 4, 3 of 3................................................................84 Table 4.17 Instructions for Application 5, 1 of 3................................................................85 Table 4.18 Instructions for Application 5, 2 of 3................................................................86 Table 4.19 Instructions for Application 5, 3 of 3................................................................86 Table 4.20 Instructions for Application 6, 1 of 3................................................................88 Table 4.21 Instructions for Application 6, 2 of 3................................................................88 Table 4.22 Instructions for Application 6, 3 of 3................................................................89 Table 5.1 Information of a converted TS file .....................................................................94 Table 5.2 Instructions for Application 7, 1 of 5..................................................................97 Table 5.3 Instructions for Application 7, 2 of 5..................................................................98 Table 5.4 Instructions for Application 7, 3 of 5..................................................................99 Table 5.5 Instructions for Application 7, 4 of 5................................................................100 viii.

(20) Table 5.6 Instructions for Application 7, 5 of 5................................................................101. ix.

(21) LIST OF FIGURES Figure 1.1 Multimedia and Communication peripherals ......................................................1 Figure 2.1 Structural overview of the documentation ..........................................................4 Figure 2.2 Ring Topology ...................................................................................................6 Figure 2.3 Rings Incorporating Splitters..............................................................................7 Figure 2.4 Star of Rings ......................................................................................................7 Figure 2.5 Control data .......................................................................................................9 Figure 2.6 Packet data.........................................................................................................9 Figure 2.7 Synchronous data...............................................................................................9 Figure 2.8 MOST Frame ...................................................................................................10 Figure 2.9 Model of a MOST Device ................................................................................12 Figure 2.10 VideoCompressor4MOST Block Diagram......................................................12 Figure 2.11 Class of Functions ..........................................................................................13 Figure 2.12 Example for a Function Interface ...................................................................15 Figure 2.13 Mapping of MOST-OSI..................................................................................16 Figure 2.14 MOST Transceiver Block Diagram ................................................................17 Figure 2.15 Virtual and real communication between two devices.....................................25 Figure 3.1 Block Diagram of the MOST System Services .................................................27 Figure 3.2 Application Socket...........................................................................................28 Figure 3.3 Basic Layer System Services............................................................................29 Figure 3.4 Low Level System Services .............................................................................31 Figure 3.5 Structure of MOST NetServices Layer 1 ..........................................................33 Figure 4.1 MOST Devices assembled for our applications ................................................39 Figure 4.2 RadioTuner4MOST .........................................................................................40 Figure 4.3 Amplifier4MOST.............................................................................................40 Figure 4.4 DVDPlayer4MOST..........................................................................................41 Figure 4.5 VideoDecoder4MOST......................................................................................41 Figure 4.6 MOST PCI Board ............................................................................................42 Figure 4.7 Optolyzer Interface Box...................................................................................42 Figure 4.8 Device Mode of MICtrl....................................................................................44 Figure 4.9 MOST Edit of MICtrl.......................................................................................44 Figure 4.10 Attaching MOST Radar to a device ................................................................45 Figure 4.11 Main Window of MOST Radar.......................................................................46 Figure 4.12 Node Symbol of MOST Radar .......................................................................47 Figure 4.13 Property Tab...................................................................................................48 Figure 4.14 Register Tab...................................................................................................49 x.

(22) Figure 4.15 Figure 4.16 Figure 4.17 Figure 4.18 Figure 4.19 Figure 4.20 Figure 4.21 Figure 4.22 Figure 4.23 Figure 4.24 Figure 4.25 Figure 4.26 Figure 4.27 Figure 4.28 Figure 4.29 Figure 4.30 Figure 4.31 Figure 4.32 Figure 4.33 Figure 4.34 Figure 4.35 Figure 4.36 Figure 4.37 Figure 4.38 Figure 4.39 Figure 4.40 Figure 4.41 Figure 4.42 Figure 4.43 Figure 4.44 Figure 4.45 Figure 4.46 Figure 4.47 Figure 4.48 Figure 4.49 Figure 4.50 Figure 4.51 Figure 4.52 Figure 4.53. Allocation Tab................................................................................................50 Report Tab .....................................................................................................51 Connect GraphEdit to Remote Graph .............................................................52 A Filter Graph Example .................................................................................52 DirectShow Filters for MOST ........................................................................53 Select Device for NSL1_EX...........................................................................54 Main Window of NSL1_EX...........................................................................55 AMS Screenshot ............................................................................................56 AMS TX buffers ............................................................................................56 Code of the function “AmsSend” ...................................................................57 An example code for using “AmsSend” .........................................................58 CMS Screenshot ............................................................................................58 CMS TX buffers ............................................................................................59 An example code for using “CtrlSendExample” .............................................60 RCS Screenshot .............................................................................................61 Perform “RemoteRead” of RCS .....................................................................61 Register mapping of MOST Transceiver on Amplifier4MOST .......................61 An example code for using “RemoteWriteExample” ......................................62 Code of the function “RemoteWriteExample” ................................................62 RadioTuner4MOST Control Program.............................................................64 DVDPlayer4MOST Control Program.............................................................66 VideoDecoder4MOST Control Program.........................................................69 Amplifier4MOST Control Program................................................................71 MOST PCI Board Control Program................................................................73 Routing Engine of MOST PCI Board .............................................................73 Routing Engine for Video Allocation of MOST PCI Board.............................74 Routing Engine for Audio Allocation of MOST PCI Board ............................75 Flow Diagram of Application 1 ......................................................................76 Screenshot of Application 1, 1 of 2.................................................................76 Screenshot of Application 1, 2 of 2.................................................................77 Flow Diagram of Application 2 ......................................................................78 Screenshot of Application 2, 1 of 2.................................................................78 Screenshot of Application 2, 2 of 2.................................................................79 Flow Diagram of Application 3 ......................................................................80 Screenshot of Application 3, 1 of 2.................................................................80 Screenshot of Application 3, 2 of 2.................................................................81 Flow Diagram of Application 4 ......................................................................82 Screenshot of Application 4, 1 of 3.................................................................82 Screenshot of Application 4, 2 of 3.................................................................83 xi.

(23) Figure 4.54 Screenshot of Application 4, 3 of 3.................................................................84 Figure 4.55 Flow Diagram of Application 5 ......................................................................85 Figure 4.56 Screenshot of Application 5, 1 of 3.................................................................85 Figure 4.57 Screenshot of Application 5, 2 of 3.................................................................86 Figure 4.58 Screenshot of Application 5, 3 of 3.................................................................86 Figure 4.59 Flow Diagram of Application 6 ......................................................................87 Figure 4.60 Screenshot of Application 6, 1 of 3.................................................................87 Figure 4.61 Screenshot of Application 6, 2 of 3.................................................................88 Figure 4.62 Screenshot of Application 6, 3 of 3.................................................................89 Figure 4.63 MOST MPEG-2 PS Capture Property Setting.................................................90 Figure 4.64 MPEG-2 Demultiplexer Property Setting .......................................................90 Figure 5.1 VideoDecoder4MOST Block Diagram .............................................................91 Figure 5.2 Rendering an Audio File by MOST Audio Channel 0 .......................................92 Figure 5.3 A/V Server User Interface ................................................................................95 Figure 5.4 Flow Diagram of Application 7 ........................................................................96 Figure 5.5 Screenshot of Application 7, 1 of 5...................................................................97 Figure 5.6 Screenshot of Application 7, 2 of 5...................................................................98 Figure 5.7 Screenshot of Application 7, 3 of 5...................................................................99 Figure 5.8 Screenshot of Application 7, 4 of 5.................................................................100 Figure 5.9 Screenshot of Application 7, 5 of 5.................................................................101 Figure 5.10 Imaginary Filter Graph of A/V Stream Rendering ........................................103. xii.

(24) CHAPTER 1 Introduction In the master thesis of my senior, Jian-Xun Wu [1], several multimedia applications of MOST (Media Oriented System Transport) are developed with the MOST NetServices API [2] (Application Programming Interface). After his graduation, I took over the experiments on MOST in our lab. Continuing with Jian-Xun Wu’s work, in this master thesis, the control program for multimedia applications of MOST will be explored and enhanced, which contributes the design of Audio/Video server under MOST network.. 1.1 MOST Technology [3] [4]. . Figure 1.1 Multimedia and Communication peripherals MOST (Media Oriented Systems Transport) is a multimedia network developed for the automotive industry. In-vehicle consumer devices such as DVD players, MP3 players, GPS systems, car phones and Bluetooth devices can be linked together to work as a single system on the MOST network. With standardized connectors and media e.g., low cost Plastic Optical 1.

(25) Fiber (POF) or Unshielded Twisted Pair (UTP), high bandwidths up to 25 Mbps and 50 Mbps are supported.. MOST technology not only includes the physical connection between devices, but also defines properties and methods for devices to interact with each other. The software interfaces allow applications running on different devices to communicate and exchange information. A transport mechanism that sets up a link for streaming data between devices is also defined.. 1.2 Scope of work The MOST devices in our lab, including the RadioTuner4MOST, Amplifier4MOST, DVDPlayer4MOST, VideoDecoder4MOST, the MOST PCI Board and the Optolyzer Interface Box, from SMSC [4], are connected in a ring topology as a multimedia network system. Via the MOST PCI Board, a PC is capable of communicating with the MOST network for management. Moreover, by means of the NetServices API, we can develop our control programs on the Windows platform to implement different multimedia applications of MOST.. Compared with Jian-Xun Wu’s work, in this thesis, the VideoDecoder4MOST will be made functional for our applications and more functions will be integrated in the control program. With a small tool combined with the new PCI Board drivers, it is possible for us to stream a media file from a PC to MOST, as an Audio/Video server.. 1.3 Structure of the Thesis Chapter 2 and Chapter 3 comprise the basics of MOST. Chapter 2 is an overview of MOST specification while Chapter 3 introduces MOST NetServices and the API. 2.

(26) In Chapter 4 before our multimedia applications of MOST are described, introductions to the hardware and software utilities are given.. In Chapter 5, the application, A/V server under MOST network, is discussed apart from those of Chapter 4.. Finally, the conclusion of this thesis is given in Chapter 6, and some possible future works for our lab are suggested, too.. 3.

(27) CHAPTER 2 MOST Specification Figure 2.1 is the structural overview of the MOST specification documentation:. Figure 2.1 Structural overview of the documentation [5] In this chapter, based on the documents “MOST Specification Framework” [6] and “MOST Specification” [5], we wish to give an introductory overview of the MOST System and its abilities. A MOST System often indicates a MOST network which is a group of MOST Devices linked together by some way.. A MOST System can be described by three definition areas which are MOST Interconnect, MOST System Services, and MOST Devices. Except MOST System Services will be introduced separately in Chapter 3, the concepts of MOST Interconnect and MOST Devices should comprise the main content of this chapter.. 4.

(28) At first, we start with MOST Topology, the way of physical interconnection between nodes. Then we get in the section of Data Transport, to see what is transported on the MOST network.. The third part of this chapter is Logical Device Model in which the logical components of a MOST device are described along with their functionalities. This section covers the contents from the application level to the lower physical layer.. For developing our applications of MOST, it is necessary to follow the MOST protocols; therefore, before moving on to the next chapter and exploring the Network Services, the protocols are introduced in the last section.. 2.1 MOST Topology [6] 2.1.1 Point to Point Link There are two basic system architectures supported by MOST Technology. The first is a one-way, point-to-point link requiring a simple transmitter on one side and a receiver on the other. This is an extremely cost effective, one-way synchronous digital connection for applications such as connecting a digital audio source to active speakers, or a digital video source to a monitor. However, this basic configuration can easily be extended to more complex structures, such as branches or bi-directional links.. 2.1.2 Ring Topology. 5.

(29) Figure 2.2 Ring Topology The second basic system architecture is a network with a ring topology. This network can have as few as two nodes, effectively a full duplex point-to-point connection, or as many as 64 nodes, as shown in Figure 2.2.. There are many advantages of a ring topology, which include the following:. Minimum use of physical layer media, reducing system cost and weight. Low overall cost and constant cost per node since there is no overhead cost in the form. of a hub, switch, or other shared network resource. Ease of expansion and no change in the basic architecture (such as the wiring. infrastructure) is required. Availability of all source data (e.g. digitized audio) at each device.. One major disadvantage of a traditional ring topology is that the failure of one node can cause the entire network to fail. However, it can be largely overcome in a MOST network. Many failure mechanisms of a node such as power loss, or loss of lock will result in the transceiver going into bypass mode such that the rest of the network is unaffected.. Variations of the ring topology are possible as well, which will be introduced in next two 6.

(30) sections. Moreover, if system speed, reliability and minimization of downtime are paramount, a dual ring topology can be used.. 2.1.2.1 Rings Incorporating Splitters. Figure 2.3 Rings Incorporating Splitters As shown in Figure 2.3, optical splitters can be incorporated into a POF (Plastic Optical Fiber) Ring creating branches connected to receive-only nodes such as display or active speaker devices. One major advantage of this implementation is reduced cost, since no transmitter is required.. 2.1.2.2 Star of Rings. Figure 2.4 Star of Rings Figure 2.4 shows a combination of Star and Ring topologies, and this may be the best choice for large networks. In structures as required for home networking such a configuration with a. 7.

(31) central server/router (i.e. set-top boxes) can have multiple branches, with each of them configured as a Ring structure. This offers the most flexible way of implementing complex structures with easy fault detection and high bandwidth.. 2.2 Data Transport Data is transferred in a continuous bi-phase encoded bit stream yielding more than a 24.8Mbps data rate, and the sample frequency in a MOST system can be chosen in a range between 30 kHz and 50 kHz. Table 2.1 Speed requirements of different applications [6]. Before discussing with the transferred data types and the frame structure of MOST, let’s take a look at Table 2.1, an overview of bandwidths needed by different applications, and how MOST fits into this picture:. 2.2.1 Data Types [6] Different types of information can be transmitted over MOST and the frame structure separates the data into three different sections: Control data, asynchronous packet data and synchronous stream data.. 8.

(32) Figure 2.5 Control data Control data transfer is for device specific transfers and system management. As shown. in Figure 2.5, control data “Eject CD” is sent to the CD player to eject the CD. This kind of data is transported in parallel to the real-time and asynchronous data.. Figure 2.6 Packet data Bulk data / burst data transfer in asynchronous packets with variable bandwidth. requirements. As shown in Figure 2.6, it is often used for TCP/IP packets between computers.. Figure 2.7 Synchronous data Real-time data transfer which requires a guaranteed bandwidth to maintain data quality.. As shown in Figure 2.7, audio stream from microphone to the speaker is such kind of data. Indeed, all nodes on the MOST network have access to it.. 2.2.2 Frame Structure [5] 2.2.2.1 Blocks A block consists of 16 frames with 512 bits (64 bytes) each, running at the system sample rate as frame rate (typical 44.1 kHz). Organization of data transfer in blocks of frames is required for network management and control data transport tasks. A control message has a fixed size 9.

(33) of 32 bytes and is time multiplexed over 16 frames (1 block), each having 2 control data bytes.. 2.2.2.2 Frames. Figure 2.8 MOST Frame Table 2.2 Structure of MOST Frame. One MOST25 frame consists of 512 bits (64 bytes). The first byte is used for administrative purposes. The next 60 bytes are used for stream and packet data transfer, where the Boundary is defined in 4 byte steps. All Stream data bytes are transmitted before any Packet data bytes occur. The next two bytes of each frame are reserved for Control data and the last byte is another administrative byte. As shown in Figure 2.8 and Table 2.2. Preamble. The preambles are used for synchronization of MOST nodes. Different mechanisms are used for Slave and Master nodes. Please refer to [5] for more details. 10.

(34) Boundary Descriptor. The value represents the number of 4 byte blocks (quadlets) of data used for synchronous data. It is used to determine the boundary between the synchronous and asynchronous data areas in the frame, on a 4 byte resolution. The Boundary can only have values between 6 and 15. Therefore, at least 24 bytes are available for Stream data transfer.. MOST System Control Bits. All other bits within the frame are for management purposes on the network level. While the preamble provides synchronization and clock regeneration, the parity bit indicates reliable data content and is used for error detection and phase lock loop operation.. 2.2.3 Transparent Channel For detailed information about control data channel, asynchronous packet data channel, synchronous data channel, and the structure of a frame in different areas, please refer to [5].. Some applications, however, may provide asynchronous data interfaces such as RS 232 and as a consequence require transparent asynchronous data transfer capability. In this case the asynchronous data lines can be oversampled at the synchronous channels and routed over the network to any other source data port.. 2.3 Logical Device Model [5]. 11.

(35) Figure 2.9 Model of a MOST Device A MOST device is a physical unit which can be connected to a MOST network via a MOST Network Interface Controller (NIC). From the logical point of view, every MOST device consists of four kinds of components which are Function Blocks, NetServices, a MOST transceiver and a Physical interface, as shown in Figure 2.9.. 2.3.1 Function Block. Figure 2.10 VideoCompressor4MOST Block Diagram [7] 12.

(36) On the application level, a MOST device contains multiple components which are called function blocks (FBlocks) in which functions are grouped together with respect to their contents. For example, Figure 2.10 is the block diagram of the VideoCompressor4MOST. There are three function blocks available: AudioVideoEncoder, AuxiliaryInput, and NetBlock.. Controller, Slave, HMI. Interaction with an FBlock requires two partners which are distributed over the MOST network: The Controller and the Slave.. The FBlock functionality resides in the Slave, and FBlocks using functions in Slaves are called Controllers. The Controller sends commands to a Slave and in return receives reports from the Slave. The Slave executes the commands issued by a Controller and sends status reports to the Controller. Controllers which have an interface to the user are called Human Machine Interfaces (HMIs).. 2.3.1.1 NetBlock The NetBlock is mandatory for every MOST device. Unlike the other function blocks which represent applications, the NetBlock controls MOST network related functions and provides access to general information for MOST network administration.. 2.3.1.2 Functions. Figure 2.11 Class of Functions 13.

(37) Functions are accessible from outside the function block via the Function Interface (FI) and can be further divided into three groups (depending on what kind of operation they perform):. • Methods are defined as functions which can be started and which lead to the result after a certain period of time. Generally they are triggered only once and are used to control the FBlocks. After a method is called, depending on what kind of operation type we use, the error or report message should be sent to the initiator.. For example, after allocating audio channels for the DVDPlayer4MOST, the results of process may be the index numbers of allocated audio channels. The following kinds of messages are exchanged via the bus for executing methods: Table 2.3 Messages for Methods. Properties are used to change or get the state of the device. For example, to change the. status of the DVDPlayer4MOST from “Play” to “Stop”. Operations allowed for each property are specified. For changing and reading of properties, the following types of messages are exchanged via the bus: Table 2.4 Messages for Properties. 14.

(38) • Events are basically the same as properties; the only distinction is that events occur without any external request.. To display the values of properties which may change without external influence, such as the current time of a CD player, a cyclical reading would be required. Without explicit requests, events which occur in a controlled FBlock initiate the sending of a status report (Notification) about the changes in properties. Thus, communication with FBlocks can be reduced.. 2.3.1.3 Function Interfaces A function interface (FI) represents the interface between a function in a FBlock, and its usage in another FBlock.. To communicate with a function, a Controller or an HMI needs information about the available parameters, their limits, and the allowed operations. In general, this information is available in the control device, and is encoded in the control program.. Figure 2.12 Example for a Function Interface Take Figure 2.12 for example, the FI contains information about the data type of the function and about minimum and maximum value. In real implementations, a FI contains more information.. 15.

(39) 2.3.2 NetServices. Figure 2.13 Mapping of MOST-OSI [8] MOST NetServices is organized into two layers where Layer 1 is the Basic Layer System Services and Layer 2 is the Application Socket. A mapping of the MOST system towards the OSI reference model is done in Figure 2.13. NetServices provides services to simplify the handling of the MOST transceiver and is an intermediate layer between the MOST transceiver and MOST FBlocks.. In the next chapter, we will have more descriptions of NetServices and its API (Application Programming Interface).. 2.3.3 MOST Transceiver and its Internal Services In addition to converting to and from the format used on the MOST network, the MOST Transceiver OS8104 of Oasis SiliconSystems provides extensive tools for operating the MOST bus.. 16.

(40) Figure 2.14 MOST Transceiver Block Diagram [8] As shown in Figure 2.14, the Transceiver has several different interfaces. It can send and retrieve information via the Control Port, the Source Data Port or via the Network Interface (optical port). The Source Data Ports are typically connected to multimedia sources and sinks which handle audio and video streams. The optical port has two pins, the receive (RX) pin and the transmit (TX) pin. They are connected to the FOT (Fiber Optical Transceiver) which can transform between electrical and optical signals.. It is also possible to get the network status out of the Power Manager and to synchronize to other systems using the Clock Manager. In this section, its internal services will be introduced.. 2.3.3.1 Bypass. Electrical Bypass (All Bypass). Each device has its own bypass function. If a bypass is activated, all signals received at the input interface are transferred directly to the output interface. In this state, the device is passive and from the MOST bus point of view, it is “invisible”. . 17.

(41) Source Data Bypass. In order to put data on the MOST network, the source data bypass should be opened (deactivated) in the device. As a result, the data is no longer passed through the chip without being processed, but can be routed from a source data port to the bus.. 2.3.3.2 Timing Master A MOST system consists of up to 64 nodes with identical MOST transceivers. In order to establish communication, one of those devices must become a Timing Master. The main task is to generate and transport the system clock, the blocks and the frames. All other devices (slaves) are synchronized with the Frame Generator by using internal PLL (Phase-Locked Loop).. 2.3.3.3 Addressing The MOST Transceiver supports four different ways of addressing: • Node Position in the ring - Automatic generating of the position during the locking procedure. • Unique Node Address (2 bytes) - An application can set unique address to a certain node. • Group Address (1 byte) - Devices with the same address numbers create a group. The group addresses can be used to control devices with the same features (e.g. speakers). • Broadcast - The broadcast address is a special group address. When used, the message is received by all nodes in the ring. During the broadcast message a control channel is locked for all other communication messages, until the acknowledgement from last device for broadcast is received.. In table 2.5, the different ways of addressing are mapped into the address area of a MOST Transceiver: 18.

(42) Table 2.5 Addressing modes vs. Address range Address range 0x0001...0x02FF 0x0500…0xFFFF 0x0400...0x04FF 0x0300...0x03C7 0c03C9...0x03FF 0x03C8. Mode Normal addressing (Point to point) based on unique node address Node position addressing: Address = 0x400 + Node position of target node Group addressed: Address = 0x300 + Address of desired group Group address 0xC8 reserved for broadcast Broadcast addressing. 2.3.3.4 Channel administration The following internal services are implemented in the MOST network to provide functional data transfer and to allocate necessary timeslots for synchronous and asynchronous data. • System Startup When the network is established every device receives a unique number starting with Timing Master 0x00 and then incremented by one for each next device. At the end of this procedure, the final value is distributed over the network (i.e. every connected device knows how many devices are connected to the bus). • Delay recognition Each MOST transceiver has information about the source data delay. By taking into consideration the fact that each device can operate in passive or active mode (bypass is open or close), every active device creates two frames of delay. • Detection of unused channels The timing master device can establish if there are some unused channels (i.e. allocated channels without any data transfer). By using resource allocation, the table re-allocation of unused channels can be recommended. • Automatic channel allocation To allocate a channel each device has to send a request to the timing master device. As a reply, information about available channels is sent. 19.

(43) 2.3.3.5 Power Management The MOST Transceiver has three power states: Normal operation mode. In normal operation mode, all sections of the chip are running and the chip is fully accessible. Low power mode. Low power mode is used to lower the power consumption of devices that are not in use at the moment. All sections of the chip that handle source data are switched off, and source data bypass is active. The chip is visible from the network’s point of view, but no communication is possible, except messages with a wakeup-preamble from the Timing Master. Zero power mode. In zero power mode, all sections of the chip are deactivated, except a small wakeup logic. The wakeup logic activates the receiving FOT unit in regular intervals and scans for modulated light. If there is modulated light, the chip wakes up.. 2.3.4 Physical Interface [6] The physical interface provides mechanical connection between the Fiber Optical Transceiver (FOT) units and the Plastic Optical Fiber (POF). In addition to that, it connects the FOT units electrically with the MOST transceiver. The Physical Layer is optimized for the use of POF as the transfer medium, but copper cable (e.g. UTP, Coax) is permissible too. In fact, the UTP (Unshielded Twisted-Pair) cable is used in the new MOST50 ePHY (electrical physical layer) as transmission media providing doubled bandwidth for new video-intensive applications.. 20.

(44) 2.4 Protocols [5] 2.4.1 Structure of MOST Protocols On the application level, the functions are addressed independently of the devices they belong to. Furthermore, the particular functions are unified into the function blocks according to their content. Hence, a function is addressed in a function block. The MOST protocols on the application layer have the following structure:. DeviceID . FBlockID . InstID . FktID . OPType . Length (Data). 2.4.1.1 DeviceID The DeviceID with a length of 16 bits, stands for a physical device or a group of devices (Group Address), and is network specific. It represents the logical node address of either the sender or the receiver, depending on the case. A group address or a broadcast address (0x03C8) could be used for the target too. In case the sender does not know the receiver’s address, the DeviceID is set to 0xFFFF and will be corrected by the NetServices of the sender.. 2.4.1.2 FBlockID It specifies particular FBlock in the device. Every function block with a special FBlockID must contain certain specific functions other than the mandatory functions. Two kinds of proprietary FBlockIDs are defined: System specific and Supplier specific. System specific type can be used by any carmaker and is predefined, where the Supplier specific type is used by OEMs (Original Equipment Manufacturer) for development purpose.. The following table shows an (incomplete) collection of FBlockIDs:. 21.

(45) Table 2.6 FBlockIDs. 22.

(46) 2.4.1.3 InstID It is an identifier of instance of function block. If the FBlockID is not unique within the system this identifier specifies the function block. FBlockID and InstID create the functional address which has to be unique. 0x01 - By default, every function block has instance ID 0x01. In case there are several. FBlocks of the same kind within one MOST device, the default number (within the device) starts at 1. 0x00 - Don’t care. The device dispatches the message to one specific FBlock in the. device. 0xFF - Broadcast (within a device). The message is dispatched to all instances of the. matching FBlock.. 2.4.1.4 FktID The FktID stands for a function. This means a function unit (Object) within a device which provides operations (e.g. “Eject CD”) can be called via the network. The FktID is encoded in 12 bits on network level and is extended to 2 bytes on application level. The address range of FktIDs is subdivided into the following sections: Coordination, Mandatory, Extensions, Unique, System Specific and Supplier Specific.. The following table regulates who is authorized to use certain FBlockID/FktID combinations. Table 2.7 Responsibilities for FBlockID and FktID ranges. 23.

(47) 2.4.1.5 OPType The OPType indicates which operation must be applied to the property or method specified in FktID: Table 2.8 OPTypes for properties and methods. Error is reported only to the Controller that has sent the instruction. On Error, an error. code is reported in the data field (Data[0]). Additional information for error codes can be found in [5].. 2.4.1.6 Length Length is encoded in 16 bits which specifies the length of the data field in bytes. This parameter is not transferred through the control channel, but is computed in the receiving node.. 24.

(48) 2.4.1.7 Data In principle, the data field of a message in the application layer (also referred to as Application Message) may have any length up to 65535 (specified by the 16-bits Length) bytes. In a telegram on the control channel of the MOST bus, the maximum length is 12 bytes. Longer protocols must be segmented, that is, be sent divided up in several telegrams. Within a data field, none, one, or multiple parameters in any combination of certain data types can be transported in a way that the parameters can be displayed directly. But please note that no floating point format would be possible here.. 2.4.2 Communication on Application Level Protocols on the application layer are described universally; hence communication on application layer is independent of the implemented physical medium. Virtually, they are transported from one application to the other, and in reality, they are transmitted with the help of Network Services and MOST NICs, as shown in Figure 2.15.. Figure 2.15 Virtual and real communication between two devices All application protocols are finally transferred via the control channel of the MOST network. From the application’s point of view, all protocols are passed on to the Network Service.. 25.

(49) CHAPTER 3 MOST NetServices This chapter consists of two parts. Section 3.1 gives an overview of MOST System Services in which MOST NetServices are included. It can be regarded as an introduction to the MOST Specification from a different point of view. In Section 3.2, MOST NetServices Layer 1 API is introduced, since we will construct our multimedia control program with the API. We survey MOST System Services and Basic Layer System Services API in this chapter, and would not go deep into the specifications.. 3.1 System Services Overview [6] The MOST System Services provide all basic functionality to operate a MOST System, and are consists of the following four parts: Application Socket Basic Layer System Services Low Level System Services Stream Services. As shown in Figure 3.1, every block in the diagram will be simply explained later.. 26.

(50) Figure 3.1 Block Diagram of the MOST System Services [5]. 3.1.1 Application Socket The Application Socket offers a wide variety of functions for building an application. Some of the functions are mandatory and some depend on the kind of application and are therefore optional. The Application Socket (Layer 2) together with the Basic Layer System Services 27.

(51) (Layer 1) are implemented in the NetServices software which contains all basic functionality a MOST Device needs.. Figure 3.2 Application Socket. 3.1.1.1 MOST Command Interpreter The MOST Command Interpreter is based on the Application Message Service of the Basic Layer. It interprets and distributes received messages to the different function blocks of a MOST Device.. 3.1.1.2 NetBlock The Net Block is a function block which is mandatory for every MOST Device. It contains basic properties of the entire device (e.g. Addresses and available function blocks).. 3.1.1.3 Network Master Shadow The Network Master is a central instance (on highest level) in a MOST network, and it handles administrative tasks like the “Central Registry”. Network Master Shadow is a local image of the Network Master which is needed for being able to receive messages of the Network Master. It is optional, since these functions can be handled in a de-central manner too.. 3.1.1.4 Address Handler, De-Central Device Registry 28.

(52) If the actual logical MOST address of a function block is unknown, this optional service seeks it anywhere in the MOST network. It is possible to keep a local device registry, which then contains the respective logical addresses.. 3.1.1.5 MOST Supervisor Layer II MOST Supervisor Layer II provides initialization of a device on highest level, e.g. of the logical address.. 3.1.1.6 Notification Service This service organizes the sending of notification messages which are sent if a property is changed.. 3.1.2 Basic Layer System Services. Figure 3.3 Basic Layer System Services The Basic Layer of the System Services is also known as MOST NetServices Layer 1 which provides comfortable access on the Low Level System Services.. 3.1.2.1 MOST Supervisor This service offers transceiver initialization and network startup on a higher level. Failure 29.

(53) diagnosis and power management are also supported by MOST Supervisor.. 3.1.2.2 Low Level Driver The Low Level Driver provides an interface between microcontroller area and the MOST transceiver. It therefore offers different interface formats. For adapting to the respective micro controller (µC) environment, the Low Level Driver is complemented by user definable hardware specific functions.. 3.1.2.3 Control Message Service The Control Message Service buffers normal control or system messages when sending and receiving. Error detection and notification is provided too. Application Message Service. When sending, this service splits application messages FBlockID.InstID.FktID.OPType(Data) into several segments with the length of 17 bytes. When receiving, segmented messages are restored to their original structure. Messages are buffered. Error detection and notification are also part of the Application Message Service. Remote Control Service. This service provides the sending and receiving of remote system messages, including error detection and notification.. 3.1.2.4 Synchronous Channel Allocation Service The Synchronous Channel Allocation Service is based upon embedded Channel Allocation which is part of the Low Level Bus Management. It allocates or de-allocates resources for real 30.

(54) time data streaming on the MOST network and “routes“ this data to the desired destination. It contains functions to make real time data handling comfortable, e.g. by providing a list of the offsets of all physical channel related to one logical channel with respect to the synchronous data stream.. 3.1.2.5 Transparent Channel Allocation Service This service provides allocating and de-allocating as well as routing of transparent data.. 3.1.2.6 Asynchronous Data Transmission Service Sending and receiving of asynchronous data is the task of this service. Errors are detected and notified.. 3.1.2.7 Transceiver Control Service This service provides access to configuration and address registers of the MOST transceiver.. 3.1.3 Low Level System Services. Figure 3.4 Low Level System Services Low Level System Services, except for the physical interface, are implemented in the MOST Transceiver (OS8104) [9].. 31.

(55) 3.1.3.1 Physical Interface As described in Section 2.3.4.. 3.1.3.2 Physical Layer The physical layer as implemented in the MOST transceiver OS 8104, provides connection of the MOST devices. In addition to that, clock recovery, data de- and encoding as well as arbitration for asynchronous channels are implemented.. 3.1.3.3 Low Level Bus Management The Low Level Bus Management provides a set of functions which handles Power Management as well as Channel Allocation for real - time data, and Node Position Sensing.. 3.1.3.4 Packet Logic Packet Logic controls sending and receiving of packet/bulk data in Packet Transmitter and Packet receiver. It includes error detection for packet data.. 3.1.3.5 Communication Management Communication management controls sending, receiving and error detection of MOST control messages (normal messages as well as system messages).. 3.1.3.6 Transaction Level Provides access to data received either as packet data, or MOST control message, and to the transmit areas for sending data (asynchronous and control).. 3.1.3.7 Real Time Transceiver 32.

(56) The Real Time Transceiver receives real time data from the external world, or sends this kind of data to the external world. In addition to that, it performs “Routing“ on real time data, that means it puts the data to the right destination (network or application).. 3.1.3.8 Format Converter The format converter converts a variety of serial source data formats (S/PDIF, Sony, Matsushita, I2S, ...) into a format that can easily be transported via MOST network, or vice versa.. 3.1.4 Stream Services The Stream Services provide transport services for real-time source data. This allows handling source data in the respective parts of the application area.. 3.2 NetServices Layer 1 API [2]. Figure 3.5 Structure of MOST NetServices Layer 1 MOST NetServices Layer 1 API is the interface between the MOST Low Level System Services and an application. All functions are combined in a library that they can be included 33.

(57) if required. MOST NetServices API is implemented in ANSI C and can be adapted by the file “adjust.h” which contains all the parameters needed to set up NetServices according to the application.. In the sections below, the available services are listed with their features, and for each of the service a brief explanation is given.. 3.2.1 MOST NetServices Kernel (MNS) ¥ Initialization of all services ¥ NetServices trigger functions. This module initializes all MOST services and implements all NetServices trigger functions i.e., callback functions.. Callback Functions. Communication between MOST NetServices and application is handled via “Callback Functions”. Those functions are called by MOST NetServices and therefore must be made available by the user in the application.. Depending on the user’s demands how the application reacts when the functions is called, Callback Functions of type “A” may be ignored, while Callback Functions of type ”B” have to return the requested value.. 3.2.2 MOST Supervisory and Startup Functions (MSV) ¥ Transceiver Initialization ¥ Master/Slave Selection 34.

(58) ¥ Compiler Selectable Source Port Configuration ¥ Network Start Up and Shut Down ¥ Power Management ¥ Failure Diagnosis and Reporting ¥ Self Testing Services. This service provides a state machine which supervises the NetInterface and influences it if needed. For more information on the state machine and its dynamic behavior, please refer to [2].. 3.2.3 Control Message Service (CMS) ¥ Initialization ¥ Control Message Receive Service ¥ Control Message Transmit Service ¥ Message Buffering and Handling ¥ Error Handling and Notification. This service allows sending and receiving of control messages. It is divided into a Tx (Transmission) and an Rx (Reception) section. Messages in both sections are represented by respective data structures, Ctrl_Tx_Type and Ctrl_Rx_Type, which will be introduced in Section 4.3.1.2.. 3.2.4 Application Message Service (AMS) ¥ Initialization ¥ Application Message Send Handler ¥ Application Message Receive Handler ¥ Message Buffering and Handling 35.

(59) ¥ Error Handling and Notification. Based on CMS, this service organizes incoming and outgoing messages on a higher level. The length of a message is no longer limited to 17 bytes. For sending and receiving application messages, AMS is separated in a TX and a RX section, so both sections are independent from each other. Since most functionalities of our program are accomplished by AMS, its usage will be explained in the next chapter.. 3.2.5 Remote Control Service (RCS) ¥ Initialization ¥ Remote Write Service ¥ Remote Read Service ¥ Remote Error Handling and Notification. This service provides the sending of remote control messages that enable the node to access registers in other transceivers. It is subdivided into the services Remote Read and Remote Write which are independent from each other.. 3.2.6 Synchronous Channel Allocation Service (SCS) ¥ Channel Allocation ¥ Allocation and Routing ¥ De-Allocation ¥ De-Allocation and Routing Disconnect ¥ Source Connect ¥ Source Disconnect ¥ Sink Connect ¥ Sink Disconnect 36.

(60) ¥ Detect Channel by Label. This service handles reserving and releasing of synchronous source data channels. It can also establish connections between the source data ports of the transceiver and the data channels. The connecting is done by writing to the Routing Engine (RE) of the MOST Transceiver.. 3.2.7 Transparent Channel Allocation Service (TCS) ¥ Channel Allocation ¥ Allocation and Routing ¥ De-Allocation ¥ De-Allocation and Routing Disconnect ¥ Source Connect ¥ Source Disconnect ¥ Sink Connect ¥ Sink Disconnect. Built up in the same modular manner as SCS, this service contains functions for reserving and releasing of channels for transporting transparent data, and for connecting inputs and outputs of the MOST Transceiver.. 3.2.8 Asynchronous Data Transmission Service (ADS) ¥ Initialize – SetDataAddress ¥ Buffered Transfer of Data Packages ¥ Buffered Receive of Data Packages ¥ Data Transfer Error Handling. It provides functionality for using asynchronous data channels. Buffers and error handling are supported. 37.

(61) 3.2.9 MOST Transceiver Control Service (MCS) ¥ Addressing ¥ Accessing important Transceiver’s Register ¥ Selecting RMCK Frequency ¥ Master Functions. This service provides functions for accessing important registers on the transceiver, to adjust certain properties like its logical address or group address. It also adds functions used by Timing Masters only.. 38.

(62) CHAPTER 4 Multimedia Applications 4.1 Hardware Overview. Figure 4.1 MOST Devices assembled for our applications In the beginning of Chapter 4, this section provides an overview of the MOST devices assembled for our applications; moreover, Figure 4.1 depicts how the devices are connected via Plastic Optical Fibers (POF) in a ring topology. Manufactured by OASIS SiliconSystems (which is now part of SMSC), the rapid prototyping devices provide a convenient way to test and demonstrate multimedia applications under MOST network. In addition to that, the MOST PCI Board and Optolyzer Interface Box are also useful to our applications.. 39.

(63) 4.1.1 RadioTuner4MOST [10]. Figure 4.2 RadioTuner4MOST The RadioTUner4MOST is a rapid prototyping tool that demonstrates the flexibility of SMSC' s application specific media controller series. The tuner is implemented using a single OS88350 Radio Controller which does all the processing necessary to implement an AM/FM receiver and puts its audio information onto a MOST network.. 4.1.2 Amplifier4MOST [11]. Figure 4.3 Amplifier4MOST The Amplifier4MOST is an 8-channel power amplifier with MOST network interface, and a rapid prototyping tool as well. It is implemented using a single OS88558 amplifier controller which does all the processing necessary to transport audio information from a MOST network to external speakers.. 40.

(64) 4.1.3 DVDPlayer4MOST [12]. Figure 4.4 DVDPlayer4MOST The rapid prototyping device, DVDPlayer4MOST, is a versatile video and audio playback system that distributes DVD video and audio as well as standard CD audio to a MOST network. The multimedia processor OS8805 from SMSC is used. The chip communicates with the MOST network and its built-in firmware controls the DVD module as well as the MPEG encoder circuitries without any glue logic.. 4.1.4 VideoDecoder4MOST [13]. Figure 4.5 VideoDecoder4MOST The VideoDecoder4MOST is a multimedia device that converts MPEG-2 streams broadcasted over a MOST network to analog A/V signals. It sends out both CVBS (Color Video Blanking Signal) composite and S-Video (Y/C) signals for an external PAL video display. An analog stereo output is available for connecting external audio amplifiers. In addition, the audio signal is digitized and may be fed into the MOST network.. 41.

(65) 4.1.5 MOST PCI Board [14]. Figure 4.6 MOST PCI Board [15] The MOST PCI Board belongs to PC Interfaces MOST25 oPHY that provide a high-speed connection between a PC and a MOST network. It is allowed to access to real-time streaming transfer, packet data transport, and control message service of the MOST network. The chip set used for PC Interfaces MOST25 oPHY consists of the OS8104 MOST Network Interface Controller and a PC interface chip. Whereas the OS8104 is used as an interface to the MOST network, the PC interface chip implements the connection to the PCI bus.. 4.1.6 Optolyzer Interface Box [16]. Figure 4.7 Optolyzer Interface Box The OptoLyzer is an analysis and development tool for exploring MOST networks. It provides full access to the MOST real-time channels as well as to control messages of a MOST network. The control and the communication of messages are available through the 115 kbps RS232 serial interface between the host and the OptoLyzer Interface Box.. 42.

(66) 4.2 Software Utilities With screenshots provided, this section introduces several software utilities which are used when implementing our multimedia applications under MOST network. They are: MOST Interface Control [17] - It is used to make communication with the MOST PCI. Board. It can also start the MOST network by setting the device as Timing Master. MOST Radar [18] - A very useful tool for gathering the information of the MOST. network. Accessing registers of the MOST Transceiver of a node is reachable. GraphEdit - With GraphEdit, we can build and test multimedia streaming applications in. block flow diagram form.. 4.2.1 MOST Interface Control MOST Interface Control (MICtrl) is a small application made by Oasis SiliconSystems, which can access the registers of the MOST Transceiver chips located in underlying MOST hardware devices like: ¥ MOST PCI Board ¥ MOST ISA Board ¥ OptoLyzer4MOST Interface Box. Please note: After upgrading the MOST PCI Board drivers from MOST25 v2.7 to MOST50 v1.4.4, it is necessary to start MICtrl before we can access the MOST PCI Board in our applications.. 4.2.1.1 Device Mode As shown in Figure 4.8, MICtrl is connected to the MOST PCI Board. Under “Device Mode”, we can set the device in “Master Mode” to start the MOST network, or leave it in “Slave Mode” that the MOST network could be started by another device. In “Slave Mode”, the 43.

(67) MOST PCI Board will behave as a regular node in the optical ring. If “Static Master Mode” is selected, the MOST Transceiver needs to be reset, and the Master will never turn off the light (i.e. even if the ring is not closed). If the device is set to “Bypass”, then it is not visible in the network.. Figure 4.8 Device Mode of MICtrl. 4.2.1.2 MOST Edit. Figure 4.9 MOST Edit of MICtrl. 44.