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Running Tesla Model 3's computer on my desk using parts from crashed cars

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Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#51

Post by bombcar »

a1o wrote: post #48

> A DC power supply capable of providing 12V Hey, I just remembered my school used to have ages ago some cool power supplies (I think from Agilent?) that were very idiot proof, they had current limit with a dial that I think didn’t went over 1A or perhaps even less, and they would instantly disarm on short circuit (and indicate it with a led), and also the voltage dial I think wouldn’t go over 25V. I remember it was…

Those were called something like desktop power supplies.

https://www.mouser.com/c/power/power-supplies/power-supplies...

AT $5k it better make me breakfast, too.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#52

Post by [deleted] »

slfnflctd wrote: post #18
girvo wrote: post #10

It's funny to hear LVDS be described as an "automotive" cable when all of my run-ins with it are for connecting laptop displays to their main-boards! (though that has a very different connector on it, and its a very general term for the signalling protocol from what I remember)

Not saying there's anything wrong with your perspective (lots of terms get in muddied waters, it's common and not a problem if everyone is on the same page), but this is what I just found on Wikipedia: "Early on, the notebook computer and LCD vendors commonly used the term LVDS instead of FPD-Link when referring to their protocol, and the term LVDS has mistakenly become synonymous with Flat Panel Display Link in the…

[deleted]

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#53

Post by virtue3 »

a1o wrote: post #48

> A DC power supply capable of providing 12V Hey, I just remembered my school used to have ages ago some cool power supplies (I think from Agilent?) that were very idiot proof, they had current limit with a dial that I think didn’t went over 1A or perhaps even less, and they would instantly disarm on short circuit (and indicate it with a led), and also the voltage dial I think wouldn’t go over 25V. I remember it was…

They have variable dc power supplies on amazon on the cheap.

If you want that sort of reliability it will probably go towards 100$.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#54

Post by duskwuff »

a1o wrote: post #48

> A DC power supply capable of providing 12V Hey, I just remembered my school used to have ages ago some cool power supplies (I think from Agilent?) that were very idiot proof, they had current limit with a dial that I think didn’t went over 1A or perhaps even less, and they would instantly disarm on short circuit (and indicate it with a led), and also the voltage dial I think wouldn’t go over 25V. I remember it was…

What you're describing is a lab power supply. (The "instantly disarm on short circuit" is overcurrent protection, which is a standard feature.) The name brands like Keysight or Rigol are kind of expensive, but there are a lot of no-name models on Amazon which will do the job well enough.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#55

Post by nandomrumber »

bluGill wrote: post #27

I used to work for a company that made third party scan tools. We had racks of ecus disconnected from the car with just a diagnostic connector and power. nothing got to a real car without first trying it on the rack. I remember on time we figured out a bmw (pre obdii) had the bytes offset from the standard documentation (it was a semi-standard protocol that some other cars used at the time), we went from we communica…

Diagnostic Trouble Codes?

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#57

Post by cbeach »

rconti wrote: post #34

I _do_ find it weird that the LCDs from crashed cars are so expensive. I wonder if newer models have better screens, so people with older cars upgrade? Or if they're a common failure point? I have a Model 3, but I can't say I follow the forums.. but I've never heard of screens failing -- I'm sure it happens but I think if it was common problem I'd have heard of it.

My 2016 Model S LCD panel developed the well-known fault of delamination and leaking some kind of sticky fluid.

Turns out the early Model S vehicles used consumer grade LCD panels that weren’t designed for the prolonged high heat you get in a metal and glass box left outside in the sun all day.

Tesla since upgraded their vehicle screens to proper automotive-grade LCDs which are excellent.

My point is, automotive-grade hardware is higher spec than regular consumer computer hardware, hence the high prices.

As an aside, I upgraded my whole computer and screen from MCU1 to MCU2 and it was worth the upgrade.

Credit to Tesla for building a retrofit computer upgrade for old vehicles. Thats a non-trivial thing to engineer and I appreciate their effort. Other car manufacturers would prefer you were compelled to buy their latest vehicle instead.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#58

Post by longislandguido »

kube-system wrote: post #13

> Turns out that actual cars don’t have individual cables. Instead they have these big “looms”, which bundle many cables from a nearby area into a single harness. This is the reason why I could not find the individual cable earlier. They simply don’t manufacture it. I was really surprised to read this at the end of the article -- how could someone be this deep into a project of this depth and not realize this?! Not o…

Software people tend to overestimate their knowledge of other disciplines, writing it off as "easy" or work beneath them. Being overpaid compared to your peers certainly doesn't help dispel this feeling. Some people have built entire careers around designing wire looms.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#59

Post by sho_hn »

guyzero wrote: post #50

Congrats, OP has recreated a test/development bench, the bane of developers working on automotive software development all around the world. They're so close to being a real vehicle that you think you'll be able to get a lot of work done, but they're not, so you don't.

Honestly I love it. Few things develop a more fun camaraderie than a bringup bootcamp with two precious/priceless new samples on a large conference table, and everyone being very careful to keep cups/mugs very far away.

And a soldering robot with a specialist a few rooms away to beam down the latest errata into physical form, at times.

Tracy Kidder just died, and Soul of a New Machine was a favorite of my formative years as an engineer. Once I started in headunit ECU development it felt very familiar to me at times.

I'm a software guy, but the gear has a lot of allure.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#60

Post by stephen_g »

slfnflctd wrote: post #18
girvo wrote: post #10

It's funny to hear LVDS be described as an "automotive" cable when all of my run-ins with it are for connecting laptop displays to their main-boards! (though that has a very different connector on it, and its a very general term for the signalling protocol from what I remember)

Not saying there's anything wrong with your perspective (lots of terms get in muddied waters, it's common and not a problem if everyone is on the same page), but this is what I just found on Wikipedia: "Early on, the notebook computer and LCD vendors commonly used the term LVDS instead of FPD-Link when referring to their protocol, and the term LVDS has mistakenly become synonymous with Flat Panel Display Link in the…

The cable in the article is pretty much doing the same conflation of terms that Wiki is talking about - the automotive one is a proprietary cable that carries some protocol that uses LVDS as its signalling, so at the most basic level both it and the display cable in the laptop are 'LVDS cables' but that's also the most generic term that gives you no information about the protocol actually being carried by the cables.
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