4 ms·
CAN bus is still really slow (1Mbps, so bus contention is a problem). Sensors, cameras, AV stuff, etc. can't all live on the CAN bus. Cars are not the same th
by thepasswordis 3y ago
CAN bus is still really slow (1Mbps, so bus contention is a problem). Sensors, cameras, AV stuff, etc. can't all live on the CAN bus. Cars are not the same things they were in the 90s.
- sbierwagen 3y ago>cameras Yes. Post 2021 teslas have nine cameras scattered all over the body. For AV, Tesla would like to get much higher resolution and frame rates out of them.
- TheLoafOfBread 3y agoCAN bus is multi-master access with automatic arbitration between nodes. Something what Ethernet is completely incapable of and that's the reason why CAN bus is here to stay for a long time. Ethernet needs active switches isolating each branch of the star network from each other. Because Ethernet working in bus mode is absolute joke, slower than CAN bus if you add enough nodes to such network. But when you need to drag all sensors and ECUs to a center of a star where is switch, where is the saving on cables? Even worse, there is no guarantee that node on such network will be able to deliver message to other node, thanks to CSMA/CD which says Random disconnection if collision. Well guess what? Your wheel just locked during braking and we need to tell that to ABS/ESP unit. When using CAN you can rectify it by using low CAN ID and thus increasing priority in arbitration. When using Ethernet, you are only praying to RNG Jesus.