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Comment: Re:This disrupts the CAN bus. (Score 1) 549

by tomtefar (#45590905) Attached to: RF Safe-Stop Shuts Down Car Engines With Radio Pulse

Since you seem a bit combative about this.

Code analysis from the Toyota sudden acceleration case: http://www.viva64.com/en/a/0083/
If the code is as horrible as described in the article, and can bug out during normal operation, it is not too far of a stretch to assume that feeding it noise on the CAN bus will induce unwanted behavior.

Also, with dynamic brake control where brake pressure is individually adjusted to maximise grip during cornering/braking (trail braking), a poorly designed brake controller may also have issues and decrease brake pressure in unwanted ways when it is being fed crap CAN frames.

Note that a CAN frame only has 15 bits of CRC, making it feasible to get a false positive on the CRC check on a 500Kbit bus with lots of traffic, thus having random data frames enter the controller code.

Those are my arguments. If you do not agree, I think we would all appreciate if you provide more counter arguments than "nope. Try again.".

Comment: This disrupts the CAN bus. (Score 5, Informative) 549

by tomtefar (#45587935) Attached to: RF Safe-Stop Shuts Down Car Engines With Radio Pulse

So the RF interference takes out the CAN bus, which runs communications between the various control units in the vehicle. This is a common problem in electrical vehicles, where the high power/current lines must be routed separately from the CAN bus wires.

There are two problems with this solution

1. Older vehicles are unaffected
Old cars, especially those with carburetors, are unaffected since they don't have any data buses that can pickup the interference.

2. The CAN bus carries safety critical information.
Corrupted data packets, such as by-wire throttle position information, can cause brake failures and/or uncontrolled acceleration when the ECU/TCU bombs out due to noise on the bus. Airbags may also deploy, although that is a bit more far-fetched.

   

Comment: Re:What's the point? (Score 3, Interesting) 187

by tomtefar (#33426758) Attached to: The Nuclear Bunker Where Wikileaks Will Be Located
More specifically, it is up to the judicial branch of the Swedish government to decide. The cabinet and parliament has very little say in how the authorities carry out the law. The few times they have tried, the Swedish press goes berserk and accuses them of minister ruling (ministerstyre), which is forbidden.
The Internet

The Puzzle of Japanese Web Design 242

Posted by kdawson
from the how-to-pack-five-eggs dept.
I'm Not There (1956) writes "Jeffrey Zeldman brings up the interesting issue of the paradox between Japan's strong cultural preference for simplicity in design, contrasted with the complexity of Japanese websites. The post invites you to study several sites, each more crowded than the last. 'It is odd that in Japan, land of world-leading minimalism in the traditional arts and design, Web users and skilled Web design practitioners believe more is more.'"
Image

The Parking Meter Turns 75 Today 126

Posted by samzenpus
from the thanks-a@#hole dept.
nj_peeps writes "75 years ago Carl Magee filed a patent application for what would become one of the most hated inventions in history: the parking meter. From the article: 'Magee's brainwave was to install a device that had a coin acceptor and a dial to engage a timing mechanism. A visible pointer and flag indicated the expiration of the paid period, meaning you either had to move, put in more money, or face the wrath of the local constabulary. The design continued largely unchanged for more than 40 years.'"

Comment: I am apparently evil. (Score 1) 623

by tomtefar (#31391210) Attached to: Whatever Happened To Programming?
For the last year, I've participated/headed our company's effort in replacing our existing python code hell with a transactional framework (in C++ with services in any language) that provides fault tolerance, easy deployment, secured event collection (because they provide billing info), load balancing, speed and scalability.

It is well documented, has example code and test cases, and it received good feedback from the rest of the devs.

I've starting to push it internally for an open source release since I thought that a framework that focuses on fault tolerance, transactional routing and scalability and other ops-oriented problems would be a good thing for the world.

Ironically enough, one of the main reasons for developing our own framework was that clobbering together ACE + X + Y + whatever would yield a framework hybrid that seemed to messy for us to rely on. We would not know the code base, be (initially) dependent on community provided bug fixes and we would still have to write a ton of glue to get everything off the ground. So after a bit of soul searching regarding Not Invented Here, we decided to strike out on our own.

However, after reading TFA, I realise that I may actually be Satan himself planning to release a new and improved rider of the apocalypse on the world.

Why is this wrong? The company is bogged down by a crappy framework with huge performance issues and unclear API boundaries. Our new framework is 20-1000 times faster, provides a clearly defined API, and is asked for by other dev teams.

Rolling our own framework gave us a single integrated (but not monolithic) codebase where the developer can log, store events, send transactions, do threads, manage signals, access DB backends and read configuration data using one API.

The framework does take ownership of the main loop, and you do need to write plugins for your services. You can, however, register your own descriptors with the poll dispatcher in order to get a callback whenever traffic happens on it. We provide a basic worker thread model, but you are free to launch as many additional threads as you want.

What did I do wrong? Should I be shot?

Comment: Re:Car analogy! (Score 1) 623

by tomtefar (#31390838) Attached to: Whatever Happened To Programming?
Letting 'what' take priority over the 'how' saves you development money for exactly one release. You will be in deep, deep yoghurt when you start planning on 2.0 of the 'what' project and realise that the previous project team just clobbered together whatever they could find in order to pass the test suite, resulting in the opposite of reusable code. The life cycle does not end with the initial release.

Comment: This does not need terminal support. (Score 1) 233

by tomtefar (#14240614) Attached to: This Text Message Will Self Destruct
This seems to be an MMS going out to the handset with a link to a web/wap site embedded in the message. Clicking this link will setup a GPRS connection to the site, which will flash the message and delete it. This is stock 3GPP usage with no protocol updates necessary. Please note, however, that it is not a text message. The sender does not use SMPP to push out a SMS message (max 160 byte) through the SMSC. This will cost both the message sender and receiver a lot more traffic than a regular SMS. /M

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