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Page 127 - Toucpad robotics C11
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    Uses in Robotics
                        High-Speed Sensor Data: Connecting  to  high-speed  sensors  like  some  Inertial Measurement  Units  (IMUs) or
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                        high-resolution Analog to Digital Converters (ADCs).
                        Display Control: Driving complex  graphical  displays,  Organic Light  Emitting  Diode  (OLED)  screens,  or Thin-Film
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                        Transistor (TFT) LCDs that require fast data updates.
                        Memory Interfaces: Communicating with flash memory, Electrically Erasable Programmable Read-Only Memory
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                        (EEPROM), or Secure Digital (SD) card modules for data logging.

                     u   Motor Driver Integration: High-performance motor drivers often use SPI for configuration and real-time control.
                     Speed and Performance
                        Highest Speed: Generally the fastest among the four protocols discussed. Speeds can range from a few Megabits per
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                        second (Mbps) to tens of Mbps, depending on the devices and wiring.
                        High Throughput: Its full-duplex nature and lack of byte-level overhead (like acknowledgement bits) lead to very high
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                        effective data throughput.

                     Error Detection and Reliability
                        Limited Built-in Error Checking: SPI itself has no standard built-in error detection mechanisms (like parity bits or
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                        acknowledgements). Data integrity relies on the quality of the connection and the devices.
                        Software Implementation: Error checking, if required, must be implemented in the software layer (e.g., by sending a
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                        Cyclic Redundancy Check checksum after data).

                     u   High Reliability for Short Distances: Highly reliable over short distances due to dedicated lines and synchronous
                        clocking.

                     Controller Area Network (CAN)

                     Description
                     Controller Area Network, commonly known as CAN, is a robust and reliable multi-master serial communication bus
                     designed for communication between Electronic Control Units (ECUs) in harsh environments, such as automobiles and
                     industrial systems. It is a message-based protocol, meaning that messages are sent based on their content (identifier)
                     rather than a specific address.
                     Key Characteristics and Differences
                        Robust and Noise Immune: Designed to operate reliably in electrically noisy environments, using differential signalling
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                        (two wires carrying opposite signals) and twisted pair cables to reduce electromagnetic interference.
                        Two Wires: Uses two wires, CAN High (CAN-H) and CAN Low (CAN-L).
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                        Multi-Master, Broadcast Communication: Any device on the network (node) can initiate communication. When a
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                        node sends a message, all other nodes on the bus receive it. Each node then decides if the message is relevant to it
                        based on its identifier.

                        Message Prioritisation and Arbitration: Every message has a unique identifier that also serves as its priority. If
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                        multiple nodes try to transmit at the same time, a non-destructive bit-wise arbitration process ensures that the
                        message with the highest priority (lowest identifier value) gets transmitted without interruption. Other messages wait
                        their turn.
                        Sophisticated Error Detection and Fault Tolerance: CAN is built with extensive error checking mechanisms and can
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                        isolate faulty nodes without disrupting the entire network.
                        Bus Topology: Typically uses a linear bus topology with terminating resistors at each end to prevent signal
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                        reflections.

                                                                                                                           125
                                                                                                     Electrical and Control Systems

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