> Jim Granville <no.spam@designtools.co.nz> wrote in message news:<pFXoc.1914$FN.207205@news02.tsnz.net>...
> > Ghazan Haider wrote:
> > > I strongly suspect it is the 8051 core. It has good maturity and is
> > > produced by many many companies.
> >
> > Yup, there are more 8051's out there than people on the planet.
>
> Why is this so popular? How/why is it better than other MCUs?
>
> Cheers,
> JonB
pervasive is not the same as popular.
They tend to be used in high volume things. Most PC keyboards use an 8051. so right there they match all the
PC CPUs made. 8 bit CPUs are powerful and cheap enough to do things that where all hardware years ago. Like
digital clocks and calculators. I heard that those blinking sneakers kids wear have a PIC in them.
>> 4-bit Asian uPs. Nothing else comes close.
>
>Do you have any idea what percentage use 6502 architecture on a 4-bit
>bus?
Not really. It depends how different from a 6502 you are willing to go
and still call it "using 6502 architecture." The fact that you can
only have 16 one-nybble instructions makes it very different already.
--
Guy Macon, Electronics Engineer & Project Manager for hire.
Remember Doc Brown from the _Back to the Future_ movies? Do you
have an "impossible" engineering project that only someone like
Doc Brown can solve? My resume is at http://www.guymacon.com/
Reply by Jim Granville●May 14, 20042004-05-14
Jon Beniston wrote:
> Jim Granville <no.spam@designtools.co.nz> wrote in message news:<pFXoc.1914$FN.207205@news02.tsnz.net>...
>
>>Ghazan Haider wrote:
>>
>>>I strongly suspect it is the 8051 core. It has good maturity and is
>>>produced by many many companies.
>>
>>Yup, there are more 8051's out there than people on the planet.
>
>
> Why is this so popular? How/why is it better than other MCUs?
It was one of the first multi-sourced, single chip microcontroller
offerings, and also built on the established 8048, with direct memory
and Boolean opcodes, plus interrupt priority and register banks.
Any patents expired a whie ago, so anyone can now make 80C51s.
Last time I looked 6 of the top 10 semi suppliers had 8051's in their
stables.
User training and experience also count - why move to a single sourced,
short design life, 'fashion core', when an 80C51 can do the task ?
8 pin and 14/16 pin 80C51s are starting to appear, so they will move
into that area as well.
ARMs are shaping up to be the 'next 80C51' in the 32 bit
microcontroller sector - so much that 16 bit MCUs are feeling the pinch
esp outside Japan.
-jg
>> 4-bit Asian uPs. Nothing else comes close.
>
>I don't doubt you'd be right if you put them all in one basket, but
>these really aren't a unified architecture, are they? I never really
>looked deeper than the assembly-langage level, but it seemed from the
>information (say) Winbond gave me, that these devices were often
>radically different. Chips from different manufacturers? Forget it. No
>family relationship, just similar feature-sets. Code compatibility and
>second-sourceing are no kind of issue for these one-time dead-end
>projects. '51, by contrast, is reasonably standard-ish from one person
>to another (clock details, peripherals, extended RAM/ROM addressing,
>etc vary of course, but that's not major).
You make a good point. On the other hand, whichever 4-bit Asian uP
is cheapest at the moment seems to get about 90% of the 4-bit market
in terms of chips sold and about 10% of the 4-bit market in terms of
profits. There are guesses, of course - the uP manufacturers don't
release such details.
At the 8051 level. architecture is important, because you are putting
serious work into the code. At the low end it really doesn't matter
which instruction set you write your 64 nybbles of code in. The code
is so simple that you can adapt to a new uP in a day.
--
Guy Macon, Electronics Engineer & Project Manager for hire.
Remember Doc Brown from the _Back to the Future_ movies? Do you
have an "impossible" engineering project that only someone like
Doc Brown can solve? My resume is at http://www.guymacon.com/
Reply by Jeff Fox●May 14, 20042004-05-14
Guy Macon <http://www.guymacon.com> wrote in message news:<Y8udnbX4-J5YGTndRVn-tA@speakeasy.net>...
> 4-bit Asian uPs. Nothing else comes close.
Do you have any idea what percentage use 6502 architecture on a 4-bit
bus?
Best Wishes
Reply by Jeff Fox●May 14, 20042004-05-14
jon@beniston.com (Jon Beniston) wrote in message news:<e87b9ce8.0405140530.1c6530c7@posting.google.com>...
> Why is this (8051) so popular? How/why is it better than other MCUs?
Because except for the newer 100Mhz chips the things can be made
on fabs that would otherwise be considered obsolete and would be
unloaded on third world contries. This means that development
costs have long since been amortized and so they cost little to
manufacture. Because their are so many old products using the
design they keep making them.
Best Wishes
Reply by Jerry Petrey●May 14, 20042004-05-14
Ghazan Haider wrote:
> I strongly suspect it is the 8051 core. It has good maturity and is
> produced by many many companies.
>
> Yet the 6502 onwards were more popular before the 8051 was (am I
> right?). What about the 68H11? is it popular at all? Ive seen many
> references to powerpc-based MCUs but never bothered to dive in. Are
> they used around much?
>
> I was opening an MP3 player at home and gave myself an exercise to
> list probabilities of various chips I might run into. ARM7 was on top
> of my list (I think I'd use it in an MP3 player), but found a 16bit ST
> chip and an ST MP3 decoder.
>
> And then I see names like the dragonball, rabbit, and other stuff I
> feel I really should know about and dont. Has civilization been built
> on the bones of the 8051 or am I self-centric?
>
> As a side question shamelessly shoved in, do people really use the
> PIC, or does Microchip make its money from students?
68HC11s are still quite popular with hobbyist in the robotics field.
Certainly the 8051 core gained a strong foothold in the microcontroller market
but as you observed, there a lot of contenders today. The PIC series is a
huge seller. I used PICs back in the mid 90's in a avionics box used on
commercial airliners (727s, 737s, Airbus, etc.) for a GPS/ILS navigation and
landing system. There are lots of choices today - it is hard to keep up with
all of them. With the new DSP entries form TI, ADI and Microchip, it gets
even more complex as these new DSP chips are now crossing over into the
microcontroller world.
At the other end, of course, are the 4 bit controllers which are still heavily
used in some markets.
Jerry
--
--------------------------------------------------------------------
-- Jerry Petrey - Senior Principal Systems Engineer
-- Navigation (GPS/INS), Guidance, & Control
-- Raytheon Missile Systems - Member Team Ada & Team Forth
-- NOTE: please remove <NOSPAM> in email address to reply
--------------------------------------------------------------------
Reply by Lewin A.R.W. Edwards●May 14, 20042004-05-14
Guy Macon <http://www.guymacon.com> wrote in message news:<Y8udnbX4-J5YGTndRVn-tA@speakeasy.net>...
> 4-bit Asian uPs. Nothing else comes close.
I don't doubt you'd be right if you put them all in one basket, but
these really aren't a unified architecture, are they? I never really
looked deeper than the assembly-langage level, but it seemed from the
information (say) Winbond gave me, that these devices were often
radically different. Chips from different manufacturers? Forget it. No
family relationship, just similar feature-sets. Code compatibility and
second-sourceing are no kind of issue for these one-time dead-end
projects. '51, by contrast, is reasonably standard-ish from one person
to another (clock details, peripherals, extended RAM/ROM addressing,
etc vary of course, but that's not major).
Reply by Uddo Graaf●May 14, 20042004-05-14
"Jon Beniston" <jon@beniston.com> wrote in message
news:e87b9ce8.0405140530.1c6530c7@posting.google.com...
> Jim Granville <no.spam@designtools.co.nz> wrote in message
news:<pFXoc.1914$FN.207205@news02.tsnz.net>...
> > Ghazan Haider wrote:
> > > I strongly suspect it is the 8051 core. It has good maturity and is
> > > produced by many many companies.
> >
> > Yup, there are more 8051's out there than people on the planet.
>
> Why is this so popular? How/why is it better than other MCUs?
>
It isn't better. It's just been around for ages and for many applications,
nothing more fancifull is needed. Besides, many companies have know-how on
using MCS-51 which makes it cost-effective for them to keep using it.
For higher-end applications, ARM is the norm. For the low-end stuff 8051.
AVR and PIC are also good contenders for the low-end stuff but AVR seems
superior. MSP430 is nice also since it has built-in LCD drivers, a must for
mass produced products (intelligent LCD displays are too expensive for mass
produced stuff).
Reply by Jon Beniston●May 14, 20042004-05-14
Jim Granville <no.spam@designtools.co.nz> wrote in message news:<pFXoc.1914$FN.207205@news02.tsnz.net>...
> Ghazan Haider wrote:
> > I strongly suspect it is the 8051 core. It has good maturity and is
> > produced by many many companies.
>
> Yup, there are more 8051's out there than people on the planet.
Why is this so popular? How/why is it better than other MCUs?
Cheers,
JonB