On Thu, 04 Mar 2010 22:45:33 -0600, "
wrote:

On Thu, 04 Mar 2010 21:42:55 -0500, wrote:

On Thu, 4 Mar 2010 14:44:16 -0800 (PST), wrote:

On Mar 4, 11:05Â*am, wrote:
On Mar 4, 12:23Â*am, wrote:





On Wed, 3 Mar 2010 07:49:16 -0800 (PST), wrote:
On Mar 3, 10:06Â*am, dpb wrote:
wrote:

...

Yes, but you missed my whole point. Â* You acknowledged that it's
desirable to have some kind of interlock to keep the car from being
shifted into at least Park while it's moving. Â* OK, so I implement
that system via an interlock system consisting of a solenoid driven by
the computer. Â* That's right, the same computer that is malfunctioning
and has the throttle pegged. Â* ...

Automotives don't use simply a single computer -- hence there is no "the
computer". Â*There are a multitude of very small (and some not so small)
microprocessors. Â*The likelihood of there being multiple systems on the
same processor is small.

Nonsense. Â*Sure there are multiple computers in a car. Â*Common ones
are for the engine control, ABS, climate control, etc. Â* But nothing
says that one computer cannot be responsible for many systems. Â*Why
would it seem unusual to have a case where the engine start/shutoff
was in the same computer as that which determines the throttle
position? Â*It is part of the engine control, is it not? Â* Â*And if
there was an electronic shift interlock, why would it be unusual for
that same computer to control it? Â* That computer is the one that
knows if the car is running, what speed it's traveling at etc.

I don't know what exactly any of the computers in these cars controls
or how the system is put together. Â* Yet, you among others, are
jumping to conclusions on what is possible or impossible without any
facts.

And in FACT, on most current production vehicles, there is either one
or 2 computers that control everything. Common practice seams to be a
PCM (Powertrain control module) and a BCM (Body control module).
The PCM handles Â*engine and transmission and all related functions -
often including cruise control, stability control, ABS, etc, while the
BCM handles the AC, power windows, sometimes cruise control etc, and
the instrument panel, among others.

SOME vehicles use only one computer to handle everything (including,
apparently, the RADIO.

Here's a much better source that says you don't know what you're
talking about:

http://www.embedded.com/columns/sign...questid=508024

For background, embedded processors are the computers that are
embedded in something else, as opposed to being a desktop, notebook,
server, etc. That something else could be your TV, cell phone,
microwave, or in this case car. They have a cpu, memory, input/output
and execute a program. Here's what they have to say about how many
of these are in cars today and it's even more than I would have
guessed. I think many here will be surprised at how high the numbers
actually are.


"How many embedded processors does your car have? Go ahead, guess. If
you've got a late-model luxury sedan, two or three processors might be
obvious in the GPS navigation system or the automatic distance
control. Yet you'd still be off by a factor of 25 or 50. The current 7-
Series BMW and S-class Mercedes boast about 100 processors apiece. A
relatively low-profile Volvo still has 50 to 60 baby processors on
board. Even a boring low-cost econobox has a few dozen different
microprocessors in it. Your transportation appliance probably has more
chips than your Internet appliance."

Like I said, there are a lot of "smart switches" in the canbus system
- but although they may use"microprocessors" they are not computers.

Tell us, how is a microprocessor (any microprocessor) *not* a computer?


A "computer" CAN include a microprocessor, but does not need to.
Google KURTA for a very good example of a strictly mechanical
"computer"
The earliest electronic computers also did not use a microprocessor,
or even a central processing unit (CPU).

A Microprocessor is a COMPUTER COMPONENT that can be used for many
processes, from the very simple to the very complex - only some of
which are "computational" or numeric in nature.

The microprocessor is used as a switch. Switches are binary digital
devices too - canbus switches are solid state and remote control. They
do NO data processing so are not REALLY computers.

Huh?


From the Columbia Encyclopedia
"computer:
device capable of performing a series of arithmetic or logical
operations. A computer is distinguished from a calculating machine,
such as an electronic calculator, by being able to store a computer
program (so that it can repeat its operations and make logical
decisions), by the number and complexity of the operations it can
perform, and by its ability to process, store, and retrieve data
without human intervention. Computers developed along two separate
engineering paths, producing two distinct types of computer-analog and
digital. An analog computer operates on continuously varying data; a
digital computer performs operations on discrete data."


If a microprocessor performs only a single operation (such as display
data on a LCD screen, or decode a signal sent across a power wire to
turn on a light remotely) it is not a computer.

If it reads several inputs and "computes" a result, and then creates
an output that does something, it is a computer, like a cruise control
computer, a transmission control computer, an ABS computer, etc.
A computer can multi-task, running numerous processes at the same
time, operating, for instance, engine fuel injection, ignition timing
and emission control, as well as controlling the transmission and
brake antilock systems - and by linking the three together also
provide traction control and active stability control - all on one
"computer"

Didn't know that. eh??

That said, even if you count them, and use a Bimmer as your example
(likely the most over-computerized space-ships in tha galaxy) finding
100 microprocessor controlled devices, muchless microprocessors, would
be a big stretch.

And counting the display driver on an LCD display as a "computer" is a
real stretch of litterary licence!!!!!