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Average car contains 100 million lines of code, The State of Autosoftware
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PlainName:

--- Quote from: MrMobodies on January 25, 2023, 12:20:12 am ---Reminds me of Toyota and the unintended vehicle acceleration.

https://www.edn.com/toyotas-killer-firmware-bad-design-and-its-consequences/

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Holy shit!  :o


--- Quote ---Vehicle tests confirmed that one particular dead task would result in loss of throttle control, and that the driver might have to fully remove their foot from the brake during an unintended acceleration event before being able to end the unwanted acceleration.
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tom66:

--- Quote from: bigfoot22 on January 25, 2023, 06:57:23 pm ---
--- Quote from: floobydust on January 25, 2023, 11:09:51 am ---Tesla's infotainment systems wearing out their FLASH memory, an embarrassing fiasco that required NHTSA pressure for a full recall. The S/W wearing out the H/W.

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Oh that makes me feel so much better about driving a gas guzzler. Thank you.

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Tesla's incompetent engineering wrt to flash has nothing to do with them making electric vehicles, nor any other EV manufacturer.
tom66:

--- Quote from: PlainName on January 25, 2023, 10:14:02 pm ---Holy shit!  :o


--- Quote ---Vehicle tests confirmed that one particular dead task would result in loss of throttle control, and that the driver might have to fully remove their foot from the brake during an unintended acceleration event before being able to end the unwanted acceleration.
--- End quote ---

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From what I remember a bug that affected some Toyota ECUs related to the cruise control handling.  The cruise control loop would read some global state variable for engine speed and gearbox selection to determine vehicle speed.  The problem was, if you crashed the sensor loop that measured engine rpm, it was possible the cruise control loop could over-run on its acceleration.  It's pretty easy to see if the cruise control is at 70 mph, but vehicle is at 69.5 mph, it might add 1% to the vehicle throttle.  If the sensor doesn't update the data, then it will continue to add to the vehicle throttle until it hits its authority limit. 

The authority limit will vary, on simpler control systems it will be just be fixed, but on more advanced systems it will use the gearbox angle sensor to provide better response, so if going uphill it will allow more power to be mixed in more quickly.  So this sensor also becomes important because if the data from that goes awry then the cruise control could be allowed to use full power on even downhill slopes.  Worst case the bit flips just as you crest a hill, cruise control  has full power authority, and you're going down the hill with throttle heading towards 100%.

According to the report I read, there's absolutely no 'stale data' handling, in any of the cruise control logic.  And this is not the only fatal design flaw in the software. 
PlainName:
I can't imagine any circumstance where I would acquire a Toyota.
SiliconWizard:
Toyota used to make pretty reliable vehicles. Until millions of lines of software code started to creep in. How sad.
Of course that's not just with Toyota. It's everywhere.

Does that mean we'll have to accept that having tons of features is more important than reliability, and take this as our new normal? And meanwhile paying millions to consulting firms that will come up with the promise of a definitive method to solve it all? :popcorn:
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