4 ms·

The problem with Ethernet is that it's (usually) not a bus. CAN is still plenty used in newer projects and they're getting even a newer higher bandwidth version

The problem with Ethernet is that it's (usually) not a bus. CAN is still plenty used in newer projects and they're getting even a newer higher bandwidth version.

chongli 3y ago
Ethernet in cars is based on the idea of putting a switch right on the die of all your microcontrollers. Then every device has multiple Ethernet links and helps to route traffic on the network. This way there’s no bulky wiring harness (bus) and everything connects with a mesh topology with single links between devices. From what I’ve heard, it can save about 100lbs of wiring per car!
- RealityVoid 3y ago
  Sounds like a routing nightmare. Do you have a more detailed reference about this? Full disclosure, I work in automotive SW, but maybe I'm not working in the right ecu to see this. Timelines for these projects are quite long.
  - chongli 3y ago
    I worked on the networking side at NXP Semiconductors who are building the chips to do all of this stuff. Here's an example of one of their recent devices built with these sorts of applications (automotive and industrial) in mind [1]. They've partnered with Bosch and TSMC on this [2]. Here's Bosch's description of the tech [3]. [1] https://www.nxp.com/products/processors-and-microcontrollers/arm-processors/i-mx-applications-processors/i-mx-9-processors/i-mx-95-applications-processor-family-high-performance-safety-enabled-platform-with-eiq-neutron-npu:iMX95 https://www.nxp.com/products/processors-and-microcontrollers... [2] https://www.nxp.com/company/about-nxp/tsmc-bosch-infineon-and-nxp-establish-joint-venture-to-bring-advanced-semiconductor-manufacturing-to-europe:NW-ESMC https://www.nxp.com/company/about-nxp/tsmc-bosch-infineon-an... [3] https://www.bosch-mobility.com/en/mobility-topics/ee-architecture/ https://www.bosch-mobility.com/en/mobility-topics/ee-archite...
    - RealityVoid 3y ago
      Ooh, that's related to the whole "domain ecu" buzz. I see a lot of push in this direction, but I'm skeptical of the direction they say they're taking. It does not make sense to me, but maybe it's just my failure to wrap my head around it all. Networking as in the SW stack or some silicon magic? Would love to pick your brain further about this if you can talk about it because so far, no one has managed to clear to me how they intend to do this magic transition to "SDV", all I saw were buzzwords and hand wavy explanations.
      - chongli 3y ago
        I worked on a pretty narrow feature so I’m not sure how it all fits together. I do know they’re really excited about TSN [1] and its potential to let you mix bulk traffic (in-vehicle entertainment stuff) with safety-critical signals and never drop the latter. I think it’s fair to say that a lot of this stuff is being pushed from the hardware side and it’ll be up to software devs to figure out how to use it all and make everything work together properly. A lot of this networking tech is being pushed down into silicon though, so on the software side you’ll just be tagging Ethernet frames and letting the hardware do the rest. [1] https://youtu.be/O5krQUbqpcY?si=QDqfoJDkczo-PwN7 https://youtu.be/O5krQUbqpcY?si=QDqfoJDkczo-PwN7

The problem with Ethernet is that it's (usually) not a bus. CAN is still plenty used in newer projects and they're getting even a newer higher bandwidth version.

chongli 3y ago

Ethernet in cars is based on the idea of putting a switch right on the die of all your microcontrollers. Then every device has multiple Ethernet links and helps to route traffic on the network. This way there’s no bulky wiring harness (bus) and everything connects with a mesh topology with single links between devices. From what I’ve heard, it can save about 100lbs of wiring per car!

RealityVoid 3y ago
Sounds like a routing nightmare. Do you have a more detailed reference about this? Full disclosure, I work in automotive SW, but maybe I'm not working in the right ecu to see this. Timelines for these projects are quite long.
- chongli 3y ago
  I worked on the networking side at NXP Semiconductors who are building the chips to do all of this stuff. Here's an example of one of their recent devices built with these sorts of applications (automotive and industrial) in mind [1]. They've partnered with Bosch and TSMC on this [2]. Here's Bosch's description of the tech [3]. [1] https://www.nxp.com/products/processors-and-microcontrollers/arm-processors/i-mx-applications-processors/i-mx-9-processors/i-mx-95-applications-processor-family-high-performance-safety-enabled-platform-with-eiq-neutron-npu:iMX95 https://www.nxp.com/products/processors-and-microcontrollers... [2] https://www.nxp.com/company/about-nxp/tsmc-bosch-infineon-and-nxp-establish-joint-venture-to-bring-advanced-semiconductor-manufacturing-to-europe:NW-ESMC https://www.nxp.com/company/about-nxp/tsmc-bosch-infineon-an... [3] https://www.bosch-mobility.com/en/mobility-topics/ee-architecture/ https://www.bosch-mobility.com/en/mobility-topics/ee-archite...
  - RealityVoid 3y ago
    Ooh, that's related to the whole "domain ecu" buzz. I see a lot of push in this direction, but I'm skeptical of the direction they say they're taking. It does not make sense to me, but maybe it's just my failure to wrap my head around it all. Networking as in the SW stack or some silicon magic? Would love to pick your brain further about this if you can talk about it because so far, no one has managed to clear to me how they intend to do this magic transition to "SDV", all I saw were buzzwords and hand wavy explanations.
    - chongli 3y ago
      I worked on a pretty narrow feature so I’m not sure how it all fits together. I do know they’re really excited about TSN [1] and its potential to let you mix bulk traffic (in-vehicle entertainment stuff) with safety-critical signals and never drop the latter. I think it’s fair to say that a lot of this stuff is being pushed from the hardware side and it’ll be up to software devs to figure out how to use it all and make everything work together properly. A lot of this networking tech is being pushed down into silicon though, so on the software side you’ll just be tagging Ethernet frames and letting the hardware do the rest. [1] https://youtu.be/O5krQUbqpcY?si=QDqfoJDkczo-PwN7 https://youtu.be/O5krQUbqpcY?si=QDqfoJDkczo-PwN7