When will the 8051 and othe 8-bits go away? - Page 3

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Re: When will the 8051 and othe 8-bits go away?
In my experience it like this- people learn a micro at collage or where
ever. They know this micro and that makes it easy for them to use. They
use it in every application, regardless of whether it is suitable or
not.
I you want to see this in action ask some one what their favorite micro
is and tell them it is crap. They immediately launch into a full on
emotional assault on you.
I have worked in Asia and have seen the 8088/8051 used in almost
everything. The most amazing one is in a controller application such as
a telephone system or PABX, it is clearly not suited to this.
 But for the above reason they continue to use it.
  The development platform is also cheap.
 Smart micro houses provide cheap development kits and software.


Re: When will the 8051 and othe 8-bits go away?
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About 1972 I built a PABX around the 8008.  I would have killed for
the 8088 or 8051.  When I left due to a disagreement with the
President the 8080 was about to come out, and I was planning a
system using two of them.  It would have been more than adequate.
One was to handle communications, and the other was the executive.
And that was a full featured PABX, with all the frills, such as
call waiting, forwarding, busy waiting, whatnot.

Please include adequate context in your posts.  Look around for
information on how to handle the insipid google usenet interface.

--
"When I want to make a man look like an idiot, I quote him."
                                               -- Mark Twain



Re: When will the 8051 and othe 8-bits go away?

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Computer manufacturers have known this for quite a few decades. Many
had educational institution prices for the hardware and the system was
often delivered loaded with all kinds of software, which for a
commercial customer would have costed a lot. By creating a pool of
graduates familiar with their system, this also helped in selling
similar systems to commercial customers, when there was a pool of
trained professionals when otherwise it was hard to find
professionals. In a few years, these people might also be selecting
the hardware.

Later on, the microprocessor vendors eagerly donated Intel Intellecs
and Motorola Exorcisers with some local media visibility. Other
processor vendors that did not donate development systems, had later
on very hard to get their processors into products designed by the
graduated students, even if the technical merits were better.

This is really not a new thing, since all vendors try to get a good
visibility in educational institutions, thus some institutions have
rules what donations they can accept and independently decide what
systems to buy, in order to avoid any unfair competition advantages.

In a growing economy with limited resources, it is tempting to get all
the donations that you can get.

Paul
    

Re: When will the 8051 and othe 8-bits go away?



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http://www.google.com/search?q=baby-duck-syndrome


Re: When will the 8051 and othe 8-bits go away?
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The DP8500 Raster Graphics Processor had a central processing unit
with 16 bit slave units and with 32 of them you had a 512 bit databus.
DIAB Data  (now focusing on compilers) built such a system already in
1988...

Graphics processors now have 128/256 bit (I think) databusses
and parallel units integrated.

There are some VLIW DSPs around with 128 bit instructions.

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--
A. P. Richelieu




Re: When will the 8051 and othe 8-bits go away?
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If you're referring to the size of the integer registers, I don't see
much justification for 128-bit and 256-bit processors.  I think the changes
to high-end processor architecture between now and 2060 are much more likely
to increase parallelism (in various forms) rather than simply make
registers and ALUs wider.

For floating point, 128-bit registers are probably reasonable, but 256-bit
is questionable.  Some current 64-bit processors have 128-bit floating
point registers.

Certainly the use of 128-bit and 256-bit hardware data busses is worthwhile
for high-end systems, and that's already done today on 32-bit and
64-bit processors.

Re: When will the 8051 and othe 8-bits go away?

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I take the bit-ness of a CPU in terms of addressing - bus sizes and such
are irrelevant as 256-bit wide buses and 128-bit SIMD registers are already
in widespread use today and there is no reason to believe we won't end up
with over 1024-bit wide (internal) buses in the near future.

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I agree with the argument 16-bit is being squeezed by both 8 and
32-bits, but they won't disappear from niches - just like there will
always remain niches for 4 and 8-bits for cost, power or pin reasons.

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Definitely.


Sounds very unlikely. The demand of 64-bit is driven by the need to
address large virtual memories, have over 4GB of RAM and the
affordability of it. 64-bits is just about enough to use as a single
virtual address space for most desktop PCs in the world (250 million
PCs each using 100GB of harddisc space), so a 64-bit virtual addresses
will be sufficient for desktop systems this century.

Having 2^64 bytes of RAM is going to be unlikely unless there are
are several major breakthroughs in the number of atoms needed to
store a bit. If current DRAM densities grew by a factor of 2 every 2
years (it is extremely optimistic to assume this rate is sustainable
indefinitely), it would take until 2070 before you could have a DIMM
with 2^64 bytes of memory.

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I don't believe any of these will ever happen. 96-bit addressing might be
adopted but even that is exceedingly unlikely - getting anywhere near that
amount of RAM would imply single bit electron or photon based storage.
More likely is that the concept of "addressing" will change radically before
we reach the 64-bit limit.

Wilco







Re: When will the 8051 and othe 8-bits go away?
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10s of uA? A few years back I made a design which included an MSP430 micro
(IIRC Flash needs more power than mask programmed), a voltage regulator (PS
was 9V), a reset controller and some chicken feed (pullups!) and it consumed
less than 5 uA. Running from a 32kHz crystal, always in active mode.
32KHz are still typical for watches. They're small and they're cheap.

Steven



Re: When will the 8051 and othe 8-bits go away?


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Back in the late 70s, TI watches drew 2 uA, and ran off of 32kHz. I would
expect that that there has been a lot of improvement since then.

-Hershel

Re: When will the 8051 and othe 8-bits go away?
On Mon, 4 Jul 2005 13:25:41 GMT, "Hershel Roberson"

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Maybe it should be 10s of nA ?

Regards
   Anton Erasmus


Re: When will the 8051 and othe 8-bits go away?
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  Present state of the art is seen in the better RTC chips, and
250-500nA is the operate current, to run the Xtal OSC and
spin a timer.

  The limit has more to do with Osc start times, Board leakage, and
real XTAL characteristics, than any silicon parameter.

  Watches have to add the stepper energy to that.

  -jg


Re: When will the 8051 and othe 8-bits go away?

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would

An RTC is a good option if you can afford one, which I couldn't in the
design I mentioned.
It allows you to leave the osc running at low power, and have the uC in
powerdown mode. The RTC timer could wake up the uC at regular intervals, uC
is up and running within microseconds, executes a few instructions and goes
back to sleep again. But even then 10nA is really low.



Re: When will the 8051 and othe 8-bits go away?
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Maybe in powerdown mode, osc off. In most apps with a 32kHz xtal not really
a good idea, as a 32kHz osc can take quite some time to become stable.



Re: When will the 8051 and othe 8-bits go away?

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Yes, but back in the late 70s watches had so few functions that they didn't
need a uC; a few counters + a few gates would do. That's a saver too.



Re: When will the 8051 and othe 8-bits go away?


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It would be quite hard to build crystal oscillators at extremely low
frequencies, the 32768 Hz was chosen as a compromise between the
resonator size and the power consumption.

In a CMOS frequency chain, the power dissipation is directly
proportional to the frequency due to the stray capacitances.

Thus, a frequency divider chain consisting of several flip-flops in
series, the first flip-flop will consume 1/2 of the chip power
consumption, the next 1/4 and the next 1/8 and so on.

However, if a uC is used, the obvious idea would be to run the
processor at the full 32768 Hz frequency, but this would increase the
power dissipation considerably, thus charging and discharging a huge
number of stray capacitances all over the chip, while in a simple
frequency divider chain, the main (1/2) power dissipation would be in
the first flip-flop.

To get really low system power consumption, the 32 kHz crystal
frequency should first be divided with a trivial frequency divider
chain to a lower value and then run the entire uC core at that
frequency (at say 1024 or even 64 Hz).  There will be a very limited
number of instructions that can be executed at such clock rates, but a
simple stopwatch application should not need too many instructions.

Paul
 

Re: When will the 8051 and othe 8-bits go away?
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Every gate will consume power, so you want as few of them as possible. Also,
in the 70s feature size was enormous to what we can get nowadays, so more
gates were more expensive. (today cost is often determined by pin count).
I don't think you could build a microcontroller with fewer transistors than
a loop counter solution. Just think of what you'd need: ALU, ROM, memory
interface, address generator (think branches)...



Re: When will the 8051 and othe 8-bits go away?
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Thanks for the article pointer, Guy. Very interesting.

Followup question:

Assuming the 8051 is the dominant 8-bit microcontroller for NEW
DESIGNS(*), do you think it will continue to be, or is there a new
rising star?

* If my assumption is wrong s/8051/dominant_mcu/

Cheers,
Paul.


Re: When will the 8051 and othe 8-bits go away?
8051 is dominant only because there are 7 different makers.
Its a very old technology on the verge of being pushed aside.
There are plenty of new 8-bit players waiting to replace the 8051.
Atmel AVR, TI 430, and god forbid the 18 series PIC.


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Re: When will the 8051 and othe 8-bits go away?
The 8051 is pobably popular because it's off-patent by now.


:Guy Macon wrote:
:> Less than 5% of the market compared to 8-bits having 30-40%.
:> http://www.techonline.com/community/ed_resource/feature_article/36930
:
:Thanks for the article pointer, Guy. Very interesting.
:
:Followup question:
:
:Assuming the 8051 is the dominant 8-bit microcontroller for NEW
:DESIGNS(*), do you think it will continue to be, or is there a new
:rising star?
:
:* If my assumption is wrong s/8051/dominant_mcu/
:
:Cheers,
:Paul.


Re: When will the 8051 and othe 8-bits go away?



Paul Marciano wrote:
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First, it depends on what "dominant" means.  If you count number
of units shipped, Elan/EMC, WinBond and SunPlus are way ahead of
8051, Pic, ARM, etc.  If you count number of engineers working on
a chip, it's the opposite.

In my opinion, for another chip to displace the 8051, it would
have to have:

[1] Good, free tools. (C Compiler, Simulator/degugger, macro
    assembler, RTOS, etc.)

[2] A bunch of variants (lots of analog I/O, USB, low voltage...)

[3] good cost/performance.

[4] All patents expired.




    



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