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More Toyota Drama


Casper

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I'll have to ask the guys at work how many lines of code are in our ABS/TCS/ESC controller

i'd be curious what they say. If that's really the case, I'll believe it, but I'd just be blown away. It's amazing just how many lines of code 100 million is. We operate our entire industrial print systems from top to bottom with under a million, i'd bet.

And i'll bet you that system does a hell of a lot more computing than a corolla does...

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Sad thing is, I doubt they really know. They aren't allowed to do anything to the code per orders from the parent company in Germany. They're basically support for US issues that funnel back to Deutschland.

One of my first co-op terms there I was looking through a bunch of lines of code, and it's pretty interesting. It's all block diagrammed and C-code generated from it, like Simulink in Matlab.

I'll still ask, but if I get an answer, take it with a grain of salt.

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Am I the only one that thinks that there's no way in the physical universe we occupy, that a Toyota has 100 million lines of code running it's combined systems?

I was on a team that made the brains for the spectrum analyzers for new generation info collections systems in planes like the awacs - that system had 43 FPGAs and took up a space the size of half an entire hockey bag and that still probably only fit about 5-10 million lines of code.

I may very well be wrong, but that number just seems way too large to me...

With OBD2, and the testing that ODB2 requires from the PCM, I bet there's a LOT more code there than most would think.

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http://en.wikipedia.org/wiki/Source_lines_of_code

Windows Server 2003 was/is 50 million lines of code, hard to believe anything in a car has more.

exactly the kind of thing I'm thinking....100 million lines of code is some serious shit.

As for the OBDII thing, that's just a diagnostics port accessing a memory map. That kind of system architecture is used everywhere (like in the last board I just made, but in FPGA form) and the code it requires is minimal at best. Trust me, I've made one from scratch in out of VHDL, and it ain't a very big deal. Having the framework already made in a CPU is even less impressive. Hell, the arbitration is the hardest part, and that's cake since there's only one port. Kind of hard to make a big deal out of a memory access arbiter that only has one port...it's like trying to ref a game that only has one team.

Let's be honest, any of the other digital EE's here will tell you that a car is (in my rough estimation) almost entirely a series of control systems. Fuel maps? They're just multi-dimensional LUT-based control algorithms. Drive-by-wire? Simple negative feedback (and maybe feed-forward) control loops. The whole thing is pretty underwhelming, and the processors they use are never leading-edge. Shit, most of these systems' loop responses are so painfully slow anyway (because they interact with mechanical systems that have crazy slow loop responses compared to clock speeds), so there's really no need for super-high-end processors or high-bandwidth comm systems.

Sure, there are a lot of controls, but this stuff really shouldn't be that hard. Or maybe the FPGA world has jaded me, and turned me into some kind of digital snob. Even though I still think drive-by-wire systems are cool in theory and scary in practice....

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When did the American driving public become so fucking stupid that this caused even one crash, let alone a fatality? Engine reving out of control? PUT IT IN NEUTRAL!! every automatic out there seamlessly pushes into neutral from drive FOR THIS EXACT REASON!! there is even a handy little stop to keep it from going into reverse. If your that dumb that a stuck throttle killed you or injured someone you love I'm sorry but you deserve it.

Bonus question. Why should you put the car in neutral an NOT shut it off? I almost shit when I heard a news anchor tell the American Idiots to shut the car off in a stuck throttle situation.

Answer? Because if you kill the engine now you loose power steering and brakes. Try stopping a car equipped with power brakes while the engine isn't running. Good luck with that.

Here's the rundown, stuck throttle? Slip trans into neutral. No damage will come to your engine the computer will limit revs to a safe, reasonable non engine destroying speed, slow and pull car to side of road, once stopped shut off ignition and place car in park. Simple you'd think.

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I was in Dweez's camp at first, but the more you look into the problem, this isn't wholly a "stupid American driver" issue - though I'd still be a major proponent for a Euro-spec driving test over here.

Granted I don't know how reliable the lady's testimony is, but she was actually in her runaway lexus and testified on Capitol Hill that she put tried the whole gamut of P-R-N-D-L and the car didn't do anything - you know why? Software controls that too - there's no hard mechanical linkage to the transmission anymore either.

http://blogs.insideline.com/straightline/MoreCategories/toyota-recalls/

Now. Mrs. Smith seemed like a perfectly honest and articulate woman, but elements of her testimony made us a little bit suspect of the story. For one, she told the House panel that she shifted the Lexus "into all available gears, including reverse, but nothing happened." Think back to the last time you shifted into reverse while a car was moving forward. Did anything happen? Even the congressmen on the panel wondered aloud why the transmission didn't just fall out of the car onto the highway. No explanation was given by anybody.
Obviously reading that text, the authors of the commentary aren't exactly in tune with some of the latest modern vehicle systems either.

There's been more than enough evidence this is a software/sensor issue that Toyota trying to sweep under the rug as a mechanical/driver issue.

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then the horriffic evil demonic piece of shit american auto industry is different, I was on the gas in my grandmothers 08 GP getting onto the freeway and was pulling a bag from the back seat into the front and I knocked it into neutral from drive. Scared me at first because I didn't know I had hit the shifter, thought the car just lost drive.

Good for the imports another job well done.

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lol, my mom had a Land Rover and she ran into the garage.

She claims she pressed on the brake and the car accelerated... I maintain that it is highly improbable that the vehicle acted in such a manner... and that she is a woman... she smacked me... my dad laughed. (I was 17 at the time)

That was fun :)

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exactly the kind of thing I'm thinking....100 million lines of code is some serious shit.

As for the OBDII thing, that's just a diagnostics port accessing a memory map.

OBDII is quite a bit more than just communicating with a scan tool. The PCM pretty much runs an emissions test while you're driving down the road. ALL of this is CODE, as they don't add any sensors for this, other than a couple more oxygen sensors.

then the horriffic evil demonic piece of shit american auto industry is different, I was on the gas in my grandmothers 08 GP getting onto the freeway and was pulling a bag from the back seat into the front and I knocked it into neutral from drive. Scared me at first because I didn't know I had hit the shifter, thought the car just lost drive.

Good for the imports another job well done.

:plus1: They need to keep some things a direct, or even just cable operated, connection.

Women Drivers = No Survivors

Nice one. I'll have to remember that one!

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