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From: David Brown on 10 Jun 2010 02:55
On 10/06/2010 00:15, Jon Kirwan wrote:
> On Wed, 9 Jun 2010 18:46:50 +0000 (UTC), Simon Clubley
> <clubley(a)remove_me.eisner.decus.org-Earth.UFP> wrote:
>
>> PIC: The Microsoft of the embedded world.
>>
>> (eg: great marketing, lousy architecture :-))
>
> It is about great support not great marketing. Engineers
> doing design aren't long fooled by marketing.
>
> Microsoft worked hard (and illegally, it turned out) to
> control market channels and sells into what is basically a
> broad-based, largely ignorant marketplace. Microchip sells
> to well-informed engineers and so far as I'm aware hasn't
> acted to force illegal contract terms onto distributers.
>
> Microchip simply supports their customers well and that
> counts for something with engineers in the end.
>

I'm not sure I agree here. A huge percentage of Microchip's user base
are /uninformed/ engineers. People pick Microchip and PICs because
that's the microcontroller they've heard of. When you are looking for
your first microcontroller, you don't know much about a company's
support - you probably don't even /think/ about support until later on
when you are having problems.

Microchip have made a very strong commitment to marketing their devices
to small users - hobby users, students, small companies, and other
first-time microcontroller users. That's how they get their customers -
companies pick them because their developers are already familiar with
the devices from their hobby days.

Great support is how Microchip /keep/ their customers. Great marketing,
especially aimed at small users, is how they get the customers in the
first place.


From: Meindert Sprang on 10 Jun 2010 02:57
"Jon Kirwan" <jonk(a)infinitefactors.org> wrote in message
news:vh4016t265upie4f0k1q0s28phj5gu6jh2(a)4ax.com...
> Use what works for you. I have to say that I found the AVR
> both excellent to work with on the first instrument I ever
> developed (it used the AT90S2313 (memory serving).) But the
> instruction set isn't by any means 'wonderful.' (I coded the
> application entirely in assembly.) There are some design
> decisions there that I considered 'poor,' even under the
> circumstances.

My first commercial product was based on the Z80. After that I did a lot of
stuff with 8051's and at a certain point I needed something faster and
explored the AVR. The instruction set gave me a dej� vu feeling of the Z80
era and I like it. Part of that project was done in assembly for speed
reasons and it worked like a charm. When I now look at the assembly of the
PIC, I just can't get my head around it to understand what is happening, the
acronyms used are so far off of my 'gut feeling' and that is important to
me. Reading AVR assembler to me is so much more 'logical' than PIC assembly.
Though my first commercial PIC project was built around a 12C508 and it
comprised a whopping 25 words of assemly code. For that project, I loved
that PIC! But looking at an 18F8720 capable of addressing 2M of program
memory, I simply cannot understand why RAM is stil accessed in 256 byte
banks.... Yuck again!!

Meindert


From: Jon Kirwan on 10 Jun 2010 05:01
On Thu, 10 Jun 2010 08:57:56 +0200, "Meindert Sprang"
<ms(a)NOJUNKcustomORSPAMware.nl> wrote:

>"Jon Kirwan" <jonk(a)infinitefactors.org> wrote in message
>news:vh4016t265upie4f0k1q0s28phj5gu6jh2(a)4ax.com...
>> Use what works for you. I have to say that I found the AVR
>> both excellent to work with on the first instrument I ever
>> developed (it used the AT90S2313 (memory serving).) But the
>> instruction set isn't by any means 'wonderful.' (I coded the
>> application entirely in assembly.) There are some design
>> decisions there that I considered 'poor,' even under the
>> circumstances.
>
>My first commercial product was based on the Z80. After that I did a lot of
>stuff with 8051's and at a certain point I needed something faster and
>explored the AVR.

I think I went a similar route, though my first consulting
work was on an 8080A, then 8085 and Z80, then 6502, then
8088, then I think HC11 and 8051 were nearby each other in
time, then more 8088 stuff, then 68332, then MIPS R2000, then
88k, and so on. The AVR as part of a real instrument and a
commercial product came perhaps around 1998, for me. The
AT90S2313.

>The instruction set gave me a dej� vu feeling of the Z80
>era and I like it. Part of that project was done in assembly for speed
>reasons and it worked like a charm.

Worked like a charm for me, too. I've no complaints on that
score.

>When I now look at the assembly of the
>PIC, I just can't get my head around it to understand what is happening, the
>acronyms used are so far off of my 'gut feeling' and that is important to
>me.

I have zero problem with the PIC. I can switch from it to a
parallel DSP, to an out-of-order execution P4, then to an
RS08, then to a nice clean 88k, and then to a MIPS R2k, one
week to the next without feeling out of sorts about any of
it. I haven't encountered an instruction set hard to grapple
with, except some truly non-standard, arcane stuff that never
really went anywhere. Like I said, instruction set is
usually at the bottom of the pile of my concerns unless the
customer places it elsewhere.

>Reading AVR assembler to me is so much more 'logical' than PIC assembly.

Hehe. Well, okay. One could just as well argue that the PIC
is more like _exposed_ logic, which technically makes it
"more logical" in another sense. It's more like what you'd
do if you only had 7400 series SSI to work with. And it is
quite logical from that standpoint. But yes, I enjoyed AVR
assembly just fine. A few gripes made me wonder "why?,"
though.

>Though my first commercial PIC project was built around a 12C508 and it
>comprised a whopping 25 words of assemly code. For that project, I loved
>that PIC! But looking at an 18F8720 capable of addressing 2M of program
>memory, I simply cannot understand why RAM is stil accessed in 256 byte
>banks.... Yuck again!!

It's been awhile for me with assembly on the PIC18F, but I
seem to recall that there are FSRs which can access all of
the memory address space (which isn't that much, really.) Or
banking. And all of the instructions can use bank 0,
directly, I seem to recall too. I don't know anything about
the 8720, though.

Jon
From: Jon Kirwan on 10 Jun 2010 05:05
On Thu, 10 Jun 2010 08:55:11 +0200, David Brown
<david(a)westcontrol.removethisbit.com> wrote:

>On 10/06/2010 00:15, Jon Kirwan wrote:
>> On Wed, 9 Jun 2010 18:46:50 +0000 (UTC), Simon Clubley
>> <clubley(a)remove_me.eisner.decus.org-Earth.UFP> wrote:
>>
>>> PIC: The Microsoft of the embedded world.
>>>
>>> (eg: great marketing, lousy architecture :-))
>>
>> It is about great support not great marketing. Engineers
>> doing design aren't long fooled by marketing.
>>
>> Microsoft worked hard (and illegally, it turned out) to
>> control market channels and sells into what is basically a
>> broad-based, largely ignorant marketplace. Microchip sells
>> to well-informed engineers and so far as I'm aware hasn't
>> acted to force illegal contract terms onto distributers.
>>
>> Microchip simply supports their customers well and that
>> counts for something with engineers in the end.
>
>I'm not sure I agree here. A huge percentage of Microchip's user base
>are /uninformed/ engineers.

Okay. So you are arguing that uninformed design engineers
are like windows computer buyers?

I can't go there. I am tempted, at times. But no.

>People pick Microchip and PICs because
>that's the microcontroller they've heard of. When you are looking for
>your first microcontroller, you don't know much about a company's
>support - you probably don't even /think/ about support until later on
>when you are having problems.
>
>Microchip have made a very strong commitment to marketing their devices
>to small users - hobby users, students, small companies, and other
>first-time microcontroller users. That's how they get their customers -
>companies pick them because their developers are already familiar with
>the devices from their hobby days.
>
>Great support is how Microchip /keep/ their customers. Great marketing,
>especially aimed at small users, is how they get the customers in the
>first place.

Well, I think we agree on the "keep" part, of course. But
the rest doesn't really dispute what I was addressing. The
person I was writing to was summing up Microchip in a
Microsoft comparison, implying that it's all just marketing.
And I know Microchip's success is not _all_ marketing or even
half marketing. I'll leave it there, though.

Jon
From: Jon Kirwan on 10 Jun 2010 05:12
On Thu, 10 Jun 2010 02:01:49 -0700, I wrote:

>I think I went a similar route, though my first consulting
>work was on an 8080A,

Earlier unpaid experiences (at university) were with IBM 1130
(asm and FORTRAN II), IBM 360 (BAL), PDP-8 (assembler),
PDP-10 (FORTRAN and ALGOL-68), PDP-11 (assembler and later in
1977/78 in c), and HP 2116 and 2114 (all assembler.) There
was a Bouroughs thing in there somewhere and an IBM System 3
and RPG II, as well, which was paid work. Starting in 1979,
I was paid to work on the VAX-11/780 in MACRO-32, BLISS-32,
C, BASIC, and COBOL. That would have been around the time
when I also began using the 6502.

Jon
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