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CAN characteristic, CAN protocol, CAN pros & cons - Coggle Diagram

- - - - Only if ALL nodes transmit recessive bit
      - Bus is idle
    - - As soon as ONE node transmit a dominant bit
- - - - bus = 1 only if all node are 1
  - - - t(pd): propagation delay of electrical medium
- - - - arbitration field = msg id field + RTR
    - - Sender send a D bit, but detect an R on bus
      - Sender send a R bit, but detect an D on bus
  - - - bit stuffing in CAN:warning:
        
        after 5 bits of 1, HW inserts a 0 bit (and after 5 bits of 0, inserts a 1 bit)
  - - - Transmitter send data frame along with CRC
      - Receiver calculate the CRC from received data, then compare to transmitter's CRC
- - - - Primary Error Flah is either 000000 or 111111
  - - - SOF[0]>[11]Standard ID>aaa>[4]DataLength>[0..64]Data>[15]CRC>CRC Deli[1]>ACK>ACK Deli[1]>[7]EOF[1]
        
        aaa: RTR[0]>IDE[0]>RBO[0]
        (RB0: reserved bit 0)
    - - SOF[0]>[11]Standard ID>bbb>[18]Extended ID>ccc>[4]DataLength>[0..64]Data>[15]CRC>CRC Deli[1]>ACK>ACK Deli[1]>[7]EOF[1]
        
        bbb: SRR[1]>IDE[1]
        ccc: RTR[0]>RB1[0]>RB0[0]
        (RB1, RB0: reserved bits)
        (IDE: ID extension - for extend ID msg)
    - - ACK bit
        
        receiver(s) respond with 0 (dominant)
        
        If no node respond => transmission failed
        
        transmitter sends 1 (recessive)
      - SRR: substitute remote request
        
        When a standard and an extended msg in an arbitration with same 11bit-ID
        => Standard msg wins, which SRR = 0
      - IDE: Identifier Extension
      - RTR: Remote Transmission Request
      - DLC: provide data length in byte, not in bit
  - - - RTR bit = 1/recessive
      - frame contains no data field