Most50 has a similar layout to most25 but with a

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MOST50 has a similar layout to MOST25 but with a larger data section. MOST150 provides two additional channels: Ethernet and Isochronous. Ethernet works like normal TCP/IP and Appletalk setups. Isochronous has three mechanisms: burst mode, constant rate, and packet streaming. Hacking MOST MOST can be hacked from a device that already supports it, such as through a vehicle’s infotainment unit or via an onboard MOST controller. The Linux- based project most4linux provides a kernel driver for MOST PCI devices and, as of this writing, supports Siemens CT SE 2 and OASIS Silicon Systems or SMSC PCI cards. The most4linux driver allows for user-space communi- cation over the MOST network and links to the Advanced Linux Sound Architecture (ALSA) framework to read and write audio data. At the moment, most4linux should be considered alpha quality, but it includes some example utilities that you may be able to build upon, namely: most_aplay Plays a .wav file ctrl_tx Sends a broadcast control message and checks status
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Bus Protocols 27 sync_tx Constantly transmits sync_rx Constantly receives The current most4linux driver was written for 2.6 Linux kernels, so you may have your work cut out for you if you want to make a generic sniffer. MOST is rather expensive to implement, so a generic sniffer won’t be cheap. The FlexRay Bus FlexRay is a high-speed bus that can communicate at speeds of up to 10Mbps. It’s geared for time-sensitive communication, such as drive-by- wire, steer-by-wire, brake-by-wire, and so on. FlexRay is more expensive to implement than CAN, so most implementations use FlexRay for high-end systems, CAN for midrange, and LIN for low-cost devices. Hardware FlexRay uses twisted-pair wiring but can also support a dual-channel setup, which can increase fault tolerance and bandwidth. However, most FlexRay implementations use only a single pair of wiring similar to CAN bus implementations. Network Topology FlexRay supports a standard bus topology, like CAN bus, where many ECUs run off a twisted-pair bus. It also supports star topology, like Ethernet, that can run longer segments. When implemented in the star topology, a FlexRay hub is a central, active FlexRay device that talks to the other nodes. In a bus layout, FlexRay requires proper resistor termination, as in a standard CAN bus. The bus and star topologies can be combined to create a hybrid layout if desired. Implementation When creating a FlexRay network, the manufacturer must tell the devices about the network setup. Recall that in a CAN network each device just needs to know the baud rate and which IDs it cares about (if any). In a bus layout, only one device can talk on the bus at a time. In the case of the CAN bus, the order of who talks first on a collision is determined by the arbitration ID.
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  • Spring '18
  • Nunya
  • Automobile, No Starch Press, Craig Smith

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