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Re: AVR or 8051

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Greed and complacency.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer:  Electronics; Informatics; Photonics.
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Re: AVR or 8051

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Lack of demand.

From a silicon vendor's point of view, setting up second
sourcing takes time and money and cuts into profits.  They're
only going to do it if enough customers demand it to make it
worthwhile.

Given a choice between older, slower, more-expensive
second-sourced parts, and newer, faster, cheaper single-sourced
parts, people picked the latter in droves.

--
Grant Edwards                   grante             Yow!  Awright, which one of
                                  at               you hid my PENIS ENVY?
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Re: AVR or 8051

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<snip more good version control/approval points>

  In this formal environment, how do you handle die revisions by the
supplier ? - Strictly, that should see a re-cycle, but I am not sure
that actually gets done :)

  Certainly a migration like AT90S2313 [EOL] to ATtiny2313 should see
the full re-approval cycle, correct ?

-jg


Re: AVR or 8051
Hi Jim,

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part
months QA
leadtimes

This is an interesting question indeed. I can tell you fersure to some
extent we rely on purchasing, which relies in turn on the manufacturers
to disclose when they are changing things. If the manufacturer doesn't
tell us there's been a die-shrink then we won't know until the ESD
damage victims start to roll into field support. We DO contractually
require them to give us notice, of course, but in theory they might
not.

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A part _number_ change automatically triggers full recertification. The
testing may well be abbreviated due to similarity, but that never seems
to translate into a shorter time period somehow.


Re: AVR or 8051
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Yes it does.
The introduction of Lead Free packaging will also mean full reapproval
and the migration from the AT89C51 to the AT89S51 needs it as well.
It shoudl be fairly safe to stay with 5 Volt parts since migration to denser
processes will not happen, but then there will not be price reductions
either.

Process shrinks will continue due to the demand for lower prices.
When the large companies say they are prepared to accept price increases to
keep the parts
in production, then they will be kept in production.
Prices cannot stay the same, since failing to shrink means that you cannot
increase
the output in the same fab/equipment.

I hardly think that is going to happen though.

--
Best Regards
Ulf at atmel dot com
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Re: AVR or 8051
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My guess is those might be the ones that will still be around in 25 years.

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Harvard MBA's:

 o Product differentiation;
 o A belief America can't compete in commodity electronics.

Result:

 o So many incompatible products that each vendor only gets a
   small slice of the pie - right back where they would have
   been if they made commodity 12th sourced uPs;
 o End Product Manufacturers faced with proprietary products
   with a short market life;
 o EPM's unable to take advantage of advanced product
   features if they want a long product lifetimes.

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I have seen that fall flat on it's face.  If the manufacturer goes
under the contract may be hard to enforce.  

I have a client who maintained a five year inventory in lieu of
no 2nd source.  The IC maker promptly went belly up after the client
took delivery of the 5 years' worth.  The client's product took
off like a rocket - the 5 year stockpile lasted less than a year.
What a way to make a flop.

OffT:

Speaking of worthless contracts:

  I once had an engineer try to sell me a patent: The firm where
  he once worked still owned the patent; But that was OK, he had an
  agreement with the President of the firm to privately sell
  the patent to non-competitors;  No, the agreement wasn't in
  writing, it was a handshake contract;  And it was really sad that
  said company President died last year;  He then confessed that the
  new owners were really litigious, and of course didn't know
  about the agreement he had with 'The Old Man', it was "sort of
  secret".

  A secret verbal contract with a dead man.

                  *      *      *

OnT:

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This has happened to me, at one time vanilla P8732's weren't available
(or so the client's purchasing department said).  A Philips with
a timer array worked just fine.  No change in the code required.

And the generics are available again.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer:  Electronics; Informatics; Photonics.
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Re: AVR or 8051


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years.

My point is that they're a limited, mediocre pool of parts now and will
be a limited, mediocre pool of parts in 25 years.

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That's part of it. Another part of it is that if a chip vendor invents
a process or peripheral that's really cool, they'll patent the design
and copyright the implementation. Another vendor who wants to offer
similar functionality at a competitive price point can't duplicate the
existing part without paying licensing fees. They are *forced* to be
incompatible, or at least different (=> not second-source candidate) if
they want to sell any parts.

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Manufacturing or designing? The evidence points strongly towards the
fact that the only way first-world countries could compete on price
would be by lowering professional incomes to third-world levels. The
only way this could work is if the entire economy was scaled down in
proportion. Not going to happen.

Simple market statistics show that consumers are strongly driven by
retail price. You might argue that a locally made product is better,
lasts longer, or gets whites whiter than white, but the point is moot
if the American DVD player is $100 and the Chinese one is $40.

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5-year
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True, but I don't think it's likely that Atmel, Philips or NEC are
going to go under in the next five years.

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:)) Let me guess, he had a bridge on offer as a gift with purchase?

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available

Try designing a device that has to last for 600,000 operations off a
single CR2032 cell and needs to fit into the handle of a rather fat
door key. See how many generic parts there are that can be used in this
application.


Re: AVR or 8051
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What has he fact that some foreign country can't compete got to do with
this? :-)

This is an international NG


/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills  Staffs  England    /\/\/\/\/\
/\/\/ snipped-for-privacy@phaedsys.org       www.phaedsys.org \/\/
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

Re: AVR or 8051
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Some architectures have (open source) FPGA cores available, which will help
long time availability.

Bye
--
Uwe Bonnes                 snipped-for-privacy@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
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Re: AVR or 8051
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  Quite true, but the long-term fish-hooks in Soft-CPUs are the silicon
  supply, and the software tools themselves.
  There really needs to be a certain 'critical mass' - and the C51
easily meets that.
-jg


Re: AVR or 8051
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help

For CPU + FPGA development, you really want to
have coverification, and AFAIK there are two ways to get that;
Send a $125,000 check to Mentor, or get the $100 STK594...


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Re: AVR or 8051

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_Two_ Years! Imagine That!

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You mean 'You will not choose Atmel', and you are correct.

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Well, that answers the question of Atmel's long-term viability.

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"ASPP" strategy and "ASSP" strategy?  That's cool.  I'll remember.

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Except on Tuesdays, I imagine.

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It might, it might (except for Invensys & uWaves).  Only time will tell,
won't it?  Lets resume discussion in the year 2030, shall we?

"Never explain, never complain".
Never explain: nobody will understand.  Never complain: nobody will care.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer:  Electronics; Informatics; Photonics.
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Re: AVR or 8051

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I cannot follow this, Jim.  Most times, I think I find myself in near or
complete agreement with you.  But not here.

When the MIPS R2000 was first released into the market (and I consider it one of
the first, if not precisely *the* first, commercially available true-RISC CPU),
one of the truly mind-boggling problems was keeping the darned thing fed from
memory.  I used 8kx8 RAM chips for the caches that were single-source at the
time (Performance Semi) and burned one watt apiece!  I haven't even mentioned
the difficulties with the connectors between the CPU board and the memory board!
The required bandwidth to memory was one of the PROBLEMS, not one of the
benefits, as you suggest above.

The reason was simple.  To get a task done, more instructions were required.
They were very fast, but you needed some 40% more memory to hold them.  And that
put pressure on memory channels.  What I really wished to have was such a CPU
with the RAM built into it, so that external chip-to-chip type drivers weren't
needed and the speeds could be more easily maintained.

Anyway, the "RISC made sense when memory was off chip" just slaps me in the
face, big time.  I know different.  From personal experience.  It was CISC that
had the advantage in terms of memory, because the code was denser.  On the other
hand, RISC was fantastic in the sense of the speed you could get by converting
all that silicon real-estate (which at the time was at a premium, but is not
nearly so these days) used for microcode and microcode sequencing logic (which
on the 68020, for example, occupied some 70% of the total die space) and turning
it into more (add new register space, multipliers, ALUs, etc.) and/or faster
(less sequential and more combinatorial) functional units.  At the time, the
trade off made tremendous sense -- especially if you weren't Motorola or Intel
and didn't have access to the very top of the line FABS and had to live in the
cracks, so to speak, with fewer transistor equivalents and still outperform the
competition who had access to 5-10X more available in their expensive FABs.)

Jon

Re: AVR or 8051

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of
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board!
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that
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  It was brief, so I will elaborate.
First I meant RAM, rather than CODE, but that may be unclear....

With a register-register core, with no direct memory opcodes, all RAM
access has a relatively high cost - but the reach of that ram tends to
be larger.
  ie just loading a 16 bit pointer costs 4 bytes in a 16 bit opcode
core, (but you can reach 64K bytes), then you need to
get/operate/putback that variable => high code cost on ALL RAM variables.

  This is the idea of opcode knee, I have mentioned before. In the
80C51, you can access 128/256 bytes in the variable length opcodes.
[ Some newer 80C51's have RAM frame pointers, to extend direct meomory
opcodes across all on chip RAM, but not many ]

  Now, if you want random access into 8K/32K of data, that's not much
benefit, but in the embedded microcontroller sector, on chip RAM is
commonly well under 1K.

  eg a DJNZ opcode in the 80C51 is 2 bytes on a reg, and 3 bytes on
any of 128 RAM locations - makes for very efficent loops.
  Atomic bit access is a natural on a 80C51

  You also confirm that RISC was a microPROCESSOR solution, not a
MicroController solution. On chip DATA memory was simply not on their
radar, but it was very much on the Radar of the 80C51 and Z8
designers, who were building a single chip microcontroller.
  The Z8 is a good example of register-register 'done right' for a uC,
and the Intel 8096 was similar.

  For larger memory systems, the ARM will become the natural next 8051,
followed closely by the Cortex respin by ARM, which takes a RISC that
was designed as a microprocessor, more into the microcontroller space,
and to improve memory usage, esp that of RAM.
- ie for a 256K Code and 64K RAM system, one would not choose a 80C51...

  Once you bring RAM on chip, (and onto the designers radar), then
a register frame pointer makes a lot of sense - as seen in the Z8,
the 166, and IIRC, in the SPARC, where they have a nice scheme for
partial register overlays, so you use some registers to pass params,
and some for local variables.

-jg


Re: AVR or 8051
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Hi Jim,

Note, he did NOT say 16 bit ACCURATE - 16 bit resolution is easy - but
do you believe the answers ???

Steve

Re: AVR or 8051
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Not true. several manufacturers to tools for the AVR (it's just not
many)

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As are many 51 tools

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Most commercial compilers do. Though check they are not time limited.

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Are there any others? there are 100's of 51 dev kits.


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No about 40 do for Silicon and a lot  more with tools  I think you will
find that virtually every silicon and IP core/fpga and ASIC manucafurer
has a 51 core. The same can not be said for the AVR.

Also the 51 family is being constantly developed. There are man new
derivatives and die shrink versions being produced that will of course
still all run the 8031 binary from the originals.


There are even versions with JTAG debugging.

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The many many tools are:-
Free ware , old and new (there are new freeware 80561 compilers being
release now. SDCC for one.

A vast area of sharware and inexpensive 52 tools both SW and HW.

Virtually ALL commercial tools manufacturers do an 8051 tool set. Again
the same is not ture for the AVR.

Some of the best (safety critical standard) compilers have free versions
that are size not time limited that are great for small projects.

there are 8051 tools that run on windows, linux and Unix.

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Yes. and LOTS of dev kits most of the 40 plus silicon vendors do their
own kits (multiple) and so does almost every other dev kit maker on the
planet.

Basically for every 1 of an AVR  tool/ code example/ etc there will be
50 in the same category for the 8051 for the 8051

The AVR is single source with comparatively few tools. The same is true
of the Philips XA. It does not make them bad parts. Technically both are
VERY good.

However unless you are doing this as a hobby there are many other
factors involved which may not make the best chip (technically) the
right part for the project.


There are many reasons for choosing the AVR or XA. Not all of them are
obvious.  In theory the Qwerty keyboard is the woest design for a
keyboard. This has been known for years but alternatives are rare in
use.


Regards
 Chris

/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills  Staffs  England    /\/\/\/\/\
/\/\/ snipped-for-privacy@phaedsys.org       www.phaedsys.org \/\/
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

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