Arbitration

• Wait for line to be quiet for a while then transmit

  • detect collision
  • average value on wire should be exactly between 1 and 0
  • if not, then two transmitters are trying to transmit data

• If collision, stop transmitting

  • wait a random amount of time and try again
  • if collide again, pick a random numberfrom a larger range (2x) and try again

• Exponential backoff on collision detection

• Try up to 16 times before reporting failure

Previous slide

Next slide

Back to first slide

View graphic version