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How Tesla is replacing the age-old CAN bus
- formerly_proven 1y agoNobody ever tried to use CAN for streaming video, because that’s not the purpose of CAN? > Tesla’s next-gen networking is all about timing - and unlike CAN, where two messages coming in at the same time can collide (resulting in neither reaching the node), > CAN is like everyone yelling in a room This is simply false. CAN uses bit arbitration and the lowest address wins.
- smnc 1y ago> CAN uses bit arbitration and the lowest address wins. And in doing so it prioritizes important messages and enables deterministic timing.
- black3r 1y ago> Nobody ever tried to use CAN for streaming video, because that’s not the purpose of CAN? How do the reversing/parking cameras work then? I always thought the reason why their feed is so low quality even in new cars was because they transmit through CAN.
- detaro 1y agoThe cameras often have dedicated cabling to the front. Sometimes analog video (probably not so much today, or only on the cheap end), sometimes digital over Coax. In other cars its using Flexray (which is a high-performance bus-system designed to be able to also support video)
- detourdog 1y agoI'm also sure somewhere Doom is running on CAN.
- amelius 1y agoCan't we just use Ethernet instead?
- formerly_proven 1y agoThe short-reach single pair Ethernet (xxxxBASE-T1) is largely developed for automotive and robotics, yes. Also supports PoE.
- liamkinne 1y agoHave a look at Ethercat. Based on the same physical layer as Ethernet but allows daisy-chaining devices.
- camtarn 1y agoSimilarly, PROFINET, the confusingly named EtherNet/IP (IP here stands for Industrial Protocol not Internet Protocol), POWERLINK, and others - all based on Ethernet but with a custom protocol layer replacing IP. "We need something that is high speed but also supports rapid deterministic communication" is pretty much a solved problem in the industrial space. I wonder what Tesla's game is here: is it really just reinventing the wheel, or are they perhaps using higher speed Ethernet as industrial Ethernet tends to still be limited to 100Mbit? Or perhaps it's tightly linked with the proposal to communicate over 48V lines?
- 1y ago
- lpcvoid 1y agoWhat a bad article. Why would you want to stream video over CAN? Also, alright, so Tesla has invented Flexray, MOST and AVB. Congratulations?
- xnx 1y ago> What a bad article. Why would you want to stream video over CAN? Rear video feed
- lpcvoid 1y agoI am aware that there's video usecases in cars, but why consider CAN for that at all? That's like streaming music via UART - yes, can be done, but why.
- xnx 1y agoIf you can't get rid of CAN completely, I believe the advantage to cramming as much stuff on there as possible is to reduce the amount of wiring.
- damnitbuilds 1y ago"CAN FD barely makes the mark for 1080p video streaming at 60fps" Maybe use CAN for what it was intended and add any new, proprietary high-speed video stuff on the side?
- Bluestein 1y agoThis. An extension or annex. Does every protocol needs to end up streaming video? Even industrial-grade stuff?
- fragmede 1y agoAh, yes, industry. A place where, famously, eyes aren't used because they're not rugged enough.
- Bluestein 1y agoHeh. That's what we need :) Ruggedized eyes.- PS. Wonder if such a thing exists in nature ...
- spwa4 1y agoIndeed. What's wrong with just sticking a usb-c hub in the cars for entertainment stuff? Oh and disconnect it from the vehicle control.
- Bluestein 1y agoRight? Or an optical network, just for that high bandwidth, "modern" stuff ... ... but for goodness sake, leave good enough alone for critical stuff.-
- detourdog 1y agoThe high speed bus should be optical.
- bayindirh 1y ago
- Bluestein 1y agoThis is just what we need: "From the same guys that brought you the Cybertruck, comes a new replacement protocol [for a tried and true thing that's been running for decades] ..." I really hope the industry sits this one out or, if needed, comes up with something better.-
- NoPicklez 1y agoIt's also "From the same guys that brought you the Tesla Model S, 3 and Y". It's easy to point the finger at a bad product a company has made and throw out all of the good. The new CAN looks to include tried and trued protocols that have existed for a while but would allow for a much better system. The combustion engine was tried and trued and didn't need changing until someone decided to do something better and electric engines are better.
- ohgr 1y agoCan’t wait for their shitty half baked software to break something critical hanging off the same bus as the cameras. (Ex model S owner - would never touch another thing they went near again)
- alternatex 1y agoIs this a website that's entire purpose is to shill for Tesla or have I become too cynical? This article for example was written to debunk Mark Rober's video on Tesla and collision avoidance: https://www.notateslaapp.com/news/2609/new-wile-e-coyote-wall-video-puts-teslas-fsd-v13-to-the-test https://www.notateslaapp.com/news/2609/new-wile-e-coyote-wal... But the arguments made against it seem quite biased towards Tesla: "However, this entire test scenario is so out of left field… there is a good likelihood this same test would fool some human drivers as well" When one of the major arguments of the video was about easy and affordable it was for the average LIDAR system to detect the wall. Of course human beings are not perfect drivers, which is why Tesla's attempt at mimicking human senses for its self driving capabilities is a bad idea. But the article seems completely ignorant of this IMO very clearly stated narrative in Mark's video.
- gonzobonzo 1y ago> But the arguments made against it seem quite biased towards Tesla: "However, this entire test scenario is so out of left field… there is a good likelihood this same test would fool some human drivers as well" The argument seems to be that running the test with FSD rather than Autopilot lead to much better results: > During this test, many people noted that Mark was using Autopilot rather than FSD...Creator Kyle Paul over on X made a much better follow-up video, using both a HW3 Model Y as well as an AI4 Cybertruck. In a relatively unsurprising turn of events, the Cybertruck was successfully able to detect the wall, slowed down, and came to a stop. The Cybertruck was running FSD 13.2.8. That seems like a valid point. Saying that you're testing Teslas self-driving car and not actually testing FSD but opting for the less advanced Autopilot feels misleading.
- alternatex 1y agoOkay FSD is better than autopilot. If we put aside Tesla-specific marketing terms, and you had an unnamed car company advertise a feature called autopilot, would you as a customer expect the car to stop when met by a wall? I wonder how it would fly in court.
- retinaros 1y agocant read stuff that is in between ads.
- numpad0 1y agoCAN bus never was the only choice of automotive buses, it's the cheapest option. There were always competing standards like FlexRay and LIN buses, just like there were Rambus RDRAM against JEDEC SDRAM or IEEE1394 against USB. It's what Mercedes pioneered, and what most high-volume manufacturers standardized on, including most Japanese and American brands. Some European companies like Volkswagen-Audi Group uses something else. I think implication of that is clear. Nissan and Toyota had been shipping cars with automotive Ethernet since as early as 2019. Including Toyota's Hydrogen EV since at least 2022. I think implication of that is also clear.
- maxerickson 1y agoLIN is simpler and less capable than CAN, to the extent CAN is cheaper at this point, it is because it has so much more volume.
- Muskisapuss 1y ago[flagged]
- jeffbee 1y agoIEEE-1394 has(d) all the logical properties this article attributes to ElonBus and it's 30 years old.
- detourdog 1y agoCan also run over optical.
- fabiofzero 1y agoMore like can't bus, amirite?
- jauntywundrkind 1y agoAnother take on the headline: > Tesla replacing common bus with wide range of somewhat interoperable tools with own proprietary bus no one else will be able to talk to