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Comment by im_down_w_otp | Hacker News Reader

Are there even any ARM Cortex-M chips that are ASIL-B rated or better?

Looks like the Cortex-R52 and Cortex-R5, a CPU and MCU, respectively both have been ASIL-D (the highest rating) qualified. Which is fantastic frankly. There's a bunch of legacy PPC, MIPS, and TriCore tech that's just miserable to work with because of their ancient and/or bespoke & proprietary toolchains. So, really the automotive industry lacks excuses that I would buy for why they're not moving forward onto new platforms other than the institutional inertia and supply-chain entanglements that its prioritizing instead.

I think the Cortex-R chips are more targeted here- I think the V8-R chips are designed specifically for automotive use, so I assume they have appropriate ratings.

There are very lazy car companies which simply specify "automotive certified" car chips for everything, including MCUs running window switches. So, don't be surprised $20 ARM-R based MCUs being used to do something trivial like driving window motor.

I seen a few dashboard where there is an STM32 sitting connected to a single button, whose only duty is to register a key press, and burp something on the CanBus in response.

I guarantee you no one is running $20 MCUs in trivial applications (in normal times). They're very cost-conscious.

A) I doubt you need a $20 component to register a key press and do some canbus IO

B) If you did have a $20 microcontroller for Canbus control of a window motor driver but it saved $19 in extra wiring/labor (driver controls usually route to all windows), provides reliable debounce, automated one-push-to-open, and allows things like holding keyless lock to close all windows, it's totally worth it.

Every component ( resistors, transistors, microcontrollers, etc ) must be Automotive qualified (AEC-Q ). That's how you have a minimum standard. A button cannot communicate on the CAN bus that's why you need the microcontroller.

A big chunk of this crisis was caused by car manufacturers being insanely focused on cost cutting. Doing obviously dumb things with BOM isn't exactly a calling card of the automotive industry.

yes. ARM sells appropriate designs, and e.g. NXP offers some chips.

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