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Comment by GeorgeTirebiter | Hacker News Reader

I maintain that most of the car's electronic guts (minus infotainment and auto-steer etc) could be done with a handful of 8051s. The problem is almost nobody it seems knows assembly anymore. The standards of CAN and LIN were created in the days of 8-bit MPUs, even I2C is quite old.

(I like assembly, but would never suggest it for a professional situation unless painted into some unforeseen corner, and assy would be the only way out.)

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As far as I've seen the shortage as it relates to electric vehicles is due to a lack of power devices, such as high power MOSFETs, not logic ICs.

This is the one thing they can't do without. Pretty hard to switch 1000A at 400V 5,000 times a second.

I would not get into a car implemented with 8051s. I entered the market on a project where an 8051 only had to manage a 2x16 character display, 16-key pad, and several motor/limit switches. The dang thing was challenged at that.

ESP32 / STM32 can do a whole heck of a lot, they're getting popular in modular synths now too. AFAIK a lot of vehicles use RTOSes for anything related to driving / vehicle stability, but I think they can use mostly whatever for infotainment, and that "whatever" seems to be largely low / mid-range stuff running absolutely garbage software that only gets updated if NHTSA makes them.

That checks out. I've contemplated getting one of those CANbus/ESP32 combos but I'm just not feeling lucky enough to muck around with my car's network for grins.

Sounds like shitty software. We did similar work with an 8051 20+ years ago and it did fine.

No, 8051 is just a sloppy piece of silicon. I wrote a symbolic linker and tokenizer for B-52 BASIC and an EPROM formatter so we could cross-develop on PC. We just had a busy little system and 8051 was not very reliable for anything realtime.

Is there a 8051-based microcontroller with the usual FLASH memory and with tools to program it like a PLC?

Hardware should be programmed like PLCs, we are just overcomplicating most hardware stuff by throwing OO & FP at it.

Squillions of them. Microchip, Silicon Labs, Infineon, and Maxim all produce such µCs, like the Silicon Labs EFM8BB - up to 50MHz, a small handful of kb of program space, a smaller on-die RAM, off you go. Or pick a more specialised IC like the Cypress FX2LP family of USB controllers - they embed an 8051 core so you can apply firmware using cheap, widely available tools.

AFAIK there are many 40nm chips that are proper arm cpus that are not that hard to get, you don't need to get to 8051 levels of ancient.

My point wasn't to encourage 8051s in cars; it was to say that many, many types of fairly mundane MPUs can do the work needed for most of the car's subsystems. Yes, Cortex M0+ chips are just fine for this, and are (relatively) blazing fast.

I know Tesla was able to pivot to different MPUs during the shortage, because the code is pretty much decently layered; so only the Low Level code to wrap the peripherals needed to change.

It's true, it's hard to replace MOSFETs when you have 1KV / hundreds of amps needs --- however, it is possible to make MOSFET arrays using lower-capable parts.

Obviously, infotainment and AI-ish tasks are not what I'm talking about.

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