/Englkfz-tech.de

Search

A     B     C     D     E     F     G     H     I     J     K     L     M     N     O     P     Q     R     S     T     U     V     W     X     Y     Z




Formulas
All Tests
Buchladen
 F7 F9



 History 1



OTA updates may have been considered with the early CAN bus, but the problems were completely different. At some point people were talking about 100 or more control units. To understand this, you would have to take a look at a modern 12V lead battery, especially the pole shoes (picture above).

There is often a small black body added to the positive. This could give you an idea of ??how small a control unit can be, not always a box like the one for engine management, for example. This might make the 'over 100' more understandable.

You need control units, even if they do the same thing, in different places. For example, if you are driving alone in the summer and want to open the window on the passenger side, you press a certain switch on the driver's door. This passes this on to its control unit, which then passes it on to the CAN bus, which in turn passes it on to the control unit on the right door, which then passes it on to the window lifter.

You can perhaps see from this how the number of control units has grown. But whether big or small, everyone claimed a place at the Lord's table. Now, very early on, a distinction has been made between, for example, drive and comfort buses, the latter being slower and therefore more cost-effective.

Then the comfort bus also became faster in some cases, but it didn't help, because this part of the vehicle equipment was massively expanded. But more and more components were also added to the drive system, for example due to emissions legislation. Above all, however, safety was at risk.

From the outset, the CAN bus was organized according to message priorities. The more important one was processed first. There was also the possibility of expansion. But at some point, messages that should have been addressed earlier were in danger of being pushed back.

So there were certain agreements right from the start, e.g. between manufacturers and suppliers, regarding the allocation of messages. The urgency was in the name. But the creation of the software was the responsibility of the individual suppliers. Only a compiled version was sent to the vehicle.

You have to know that software is produced in a certain language, if it is not a very special one, you can probably still assume C++ or Java. If this were offered to a microprocessor, it would do nothing.

That's why there are so-called compilers that turn these line-by-line work instructions into a kind of machine language that the microprocessor understands. This alone means already that a different code is created for different processors.

What is not possible, however, is converting this code back to C++ in order to make additions, for example. There is one way to make the zeros and ones understandable at all, and this is called an assembler. But here the relationships contained in C++, for example, are completely dissolved.

To understand this, here is a story from our recent past. Suddenly, out of the blue, our hard drive for the internal backup of our data no longer wanted to give it up. We wanted to save money on services and resorted to software.

To understand this, here is a story from our recent past. Suddenly, out of the blue, our hard drive for the internal backup of our data no longer wanted to give it up. We wanted to save money on services and resorted to software.

The example only reflects the level of difficulty when working with assembler. Anyone who is very experienced in this language can also develop independent programs in it. Experts have discovered, for example, that Bosch had provided for branches in its diesel engine software.

Bosch has left open whether these were used for certain functions to deceive in emissions tests. Legal uses would also have been possible, for example to protect the engine in a certain, critical situation.

Programming in assembler works completely differently than in a normal programming language, so it is not suitable for development work.







Sidemap - Technik Imprint E-Mail Datenschutz Sidemap - Hersteller