Re: microcontrollers for process control

"Spehro Pefhany" <speffSNIP@xxxxxxxxxxxxxxxxxxxxxxx> skrev i meddelandet
news:4s9jt3ln05beeqm30apccat69095tee43l@xxxxxxxxxx
On Tue, 11 Mar 2008 23:08:48 -0500, CBFalconer <cbfalconer@xxxxxxxxx>
wrote:

Ulf Samuelsson wrote:
"a_edwards" <eecoding@xxxxxxxxxxx> skrev:

... snip ...

yes that is good thanks. But i want a example of what is
currently used ny a manufacturer. If the system was for a large
building would not they use a 16 bit micro?

Yes, it is not well known but if the building has more than 8
levels, you *have* to use a 16 bit controller or better! If it
goes beyond 16 levels, you have to move up to a 32 bitter ;-)

If I hadn't been so lazy, I would have applied for a U.S. patent
for using a 32 bit MCU in a fire alarm if the building has more
than 16 levels.

Either that is utter nonsense or I am missing something. There is
no relation between interrupts available and 'levels'. There is a
relationship between code complexity and levels. And someone has
to decide how to break up the interrupts. But one would suffice,
combined with suitable i/o.

No, I think you'd definitely need a 32-bitter if there are more than
16 floors (including penthouse, basement and sub-basement levels).
They must use something like ganged 64-bit processors for Taipei 101.

No, if you think that through, you will realize that this won't work!

For info on how to handle buildings taller than 64 levels,
you need to dig into the promising VHIW
(Very High Instruction Word) architecture.


Best regards,
Spehro Pefhany
--



--
Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may not be shared by my employer Atmel Nordic AB


.

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