Single-Source PIC, AVR & Alternatives

Tim Wescott wrote:

> I am currently working with a client who is designing a PIC 
> microprocessor into his system.  It may be too late to change, but I am 
> being reminded of all the drawbacks to writing software for the PIC.
> 
> I heard from a committed PIC booster that "yes, the architecture sucks 
> for programming, but the PIC never has delivery problems".  Choosing a 
> processor that my client couldn't get down the road would trump any pain 
> I may experience with less than beautiful code.
> 
> Does anyone have experience with alternatives to the PIC (and 8051 
> derivatives) that show that this is not a problem?  The ones that come 
> to my mind the soonest are the AVR and the MSP430xxx lines, although I'm 
> sure that there are German and Japanese alternatives as well.  The story 
> I heard about delivery problems was specifically about "Atmel doesn't 
> understand that it's single-source".
> 
> Thanks in advance.
> 
This has been a really interesting thread to read, with all the opinions 
and all.

But what I'm curious about is which companies have you had good 
experiences with over the years, and which ones have left you feeling 
like you'll never be dumb enough to design one of their parts into a 
product ever again?

Thanks in advance.

-- 

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Posting from Google?  See http://cfaj.freeshell.org/google/

"Applied Control Theory for Embedded Systems" came out in April.
See details at http://www.wescottdesign.com/actfes/actfes.html

On Sat, 09 Dec 2006 07:54:19 -0800, Tim Wescott <tim@seemywebsite.com> wrote:

>I am currently working with a client who is designing a PIC 
>microprocessor into his system.  It may be too late to change, but I am 
>being reminded of all the drawbacks to writing software for the PIC.
>
>I heard from a committed PIC booster that "yes, the architecture sucks 
>for programming, but the PIC never has delivery problems".  Choosing a 
>processor that my client couldn't get down the road would trump any pain 
>I may experience with less than beautiful code.
>
>Does anyone have experience with alternatives to the PIC (and 8051 
>derivatives) that show that this is not a problem?  The ones that come 
>to my mind the soonest are the AVR and the MSP430xxx lines, although I'm 
>sure that there are German and Japanese alternatives as well.  The story 
>I heard about delivery problems was specifically about "Atmel doesn't 
>understand that it's single-source".

AFAIK Microchip is the only vendor who has always had a stated policy of short leadtimes, typically
3-4 weeks max on the rare occasions that a part isn't in stock, and a dedicated line to
build-on-demand quickly for panic orders. And a track record to back it up.
Another thing I read in one of their glossies a while ago is that no single customer represents more
than 3% of their business, so less chance of a big order suddenly wiping out a chunk of production
capacity. The fact that they have always supported  low-volume users means there is plenty of stock
out there. 
The wide range of parts, and general pin-compatibility as you go up the range also means there is
often an alternative part that will go in the same socket with little or no software change.

If you're writing in C, the architecture doesn't really make much difference unless you're pushing
the limits of code space or speed.  

On Sat, 09 Dec 2006 18:57:32 -0600, Ben Jackson <ben@ben.com> wrote:

>On 2006-12-09, Tim Wescott <tim@seemywebsite.com> wrote:
>> being reminded of all the drawbacks to writing software for the PIC.
>
>If you decide you want C for the PIC, you should buy one of the
>commercial offerings.  I've used SDCC (free) off and on for pic14 (12F*,
>16F*) and pic16 (18F*) and you constantly have to check the assembly
>for problems.  I keep telling myself that I should not try to use up
>my supply of PICs but instead throw them away and save myself the
>irritation.
>
>> to my mind the soonest are the AVR and the MSP430xxx lines,
>
>How single is single?  Lots of AVRs have similar capabilities and
>compatible footprints.  They're also better than Microchip about making
>the transition to upgraded parts easy.

I'd dispute that. In most cases Microchip just add peripherals, leaving the reset the same, as well
as keeping the pinout back-compatible.  e.g.  18F4520,  has the same pinout as the 16C74 four
generations ago. 
Atmel have historically fiddled around with subtle changes in both hardware and software ( e.g.
mega8->mega88), leaving a trail of unnecessarily different and incompatible parts in the wake of
progress. 

On Sat, 09 Dec 2006 22:33:04 -0800, Tim Wescott <tim@seemywebsite.com> wrote:

>Tim Wescott wrote:
>
>> I am currently working with a client who is designing a PIC 
>> microprocessor into his system.  It may be too late to change, but I am 
>> being reminded of all the drawbacks to writing software for the PIC.
>> 
>> I heard from a committed PIC booster that "yes, the architecture sucks 
>> for programming, but the PIC never has delivery problems".  Choosing a 
>> processor that my client couldn't get down the road would trump any pain 
>> I may experience with less than beautiful code.
>> 
>> Does anyone have experience with alternatives to the PIC (and 8051 
>> derivatives) that show that this is not a problem?  The ones that come 
>> to my mind the soonest are the AVR and the MSP430xxx lines, although I'm 
>> sure that there are German and Japanese alternatives as well.  The story 
>> I heard about delivery problems was specifically about "Atmel doesn't 
>> understand that it's single-source".
>> 
>> Thanks in advance.
>> 
>This has been a really interesting thread to read, with all the opinions 
>and all.
>
>But what I'm curious about is which companies have you had good 
>experiences with over the years, and which ones have left you feeling 
>like you'll never be dumb enough to design one of their parts into a 
>product ever again?
>
>Thanks in advance.

I would never be worried about availability issues of a Microchip part (qualifier _once in full
production_). 
Atmel kick ass cost-wise on higher end parts ( e.g. mega88 vs. 18f4520) , but it is yet to be seen
whether they have learned from their historical availability nightmares (Anyone remember 52 week
leadtimes a while ago..?).
Unfortunately Atmel's own devtools suck, and there is no real in-circuit emulator for the current
parts. 
Microchip are streets ahead in this aspect, and for complex projects this alone is a good reason for
using them. 

On Sat, 09 Dec 2006 22:33:04 -0800, the renowned Tim Wescott
<tim@seemywebsite.com> wrote:

>Tim Wescott wrote:
>
>> I am currently working with a client who is designing a PIC 
>> microprocessor into his system.  It may be too late to change, but I am 
>> being reminded of all the drawbacks to writing software for the PIC.
>> 
>> I heard from a committed PIC booster that "yes, the architecture sucks 
>> for programming, but the PIC never has delivery problems".  Choosing a 
>> processor that my client couldn't get down the road would trump any pain 
>> I may experience with less than beautiful code.
>> 
>> Does anyone have experience with alternatives to the PIC (and 8051 
>> derivatives) that show that this is not a problem?  The ones that come 
>> to my mind the soonest are the AVR and the MSP430xxx lines, although I'm 
>> sure that there are German and Japanese alternatives as well.  The story 
>> I heard about delivery problems was specifically about "Atmel doesn't 
>> understand that it's single-source".
>> 
>> Thanks in advance.
>> 
>This has been a really interesting thread to read, with all the opinions 
>and all.
>
>But what I'm curious about is which companies have you had good 
>experiences with over the years, and which ones have left you feeling 
>like you'll never be dumb enough to design one of their parts into a 
>product ever again?
>
>Thanks in advance.

Some companies (Motorola, now Freescale) and Atmel have a history of
supplying large customers at the expense of smaller ones in times of
shortage. Microchip has a business strategy of keeping lead times
reasonable (stock to 4 weeks, IIRC). So far, they seem to be doing it.
Their customer base is also not as dependent on volatile sectors such
as automotive (Freescale) or cell phones (Atmel), AFAIUI.  


Best regards, 
Spehro Pefhany
-- 
"it's the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

"Tim Wescott" <tim@seemywebsite.com> schrieb im Newsbeitrag
news:KPCdnY4OvJCVNObYnZ2dnUVZ_v3inZ2d@web-ster.com...
> I understand that if I want to use a microprocessor with peripherals
> that I'm saying goodby to second source.  What I want is to know which
> microprocessors companies have the best track records of taking care of
> their single-sourced customers.

I never thought there is a un-answerable question. Here it is!

It depends simply on volume. If you are one of the big player you always
have a source - as long as you want.

Personally I look on the support and openess of information policy. That is
a good indication for later business relationship.


- Henry


--
www.ehydra.dyndns.info

"Tim Wescott" <tim@seemywebsite.com> schrieb im Newsbeitrag
news:KPCdnYkOvJCIN-bYnZ2dnUVZ_v3inZ2d@web-ster.com...
> But what I'm curious about is which companies have you had good
> experiences with over the years, and which ones have left you feeling
> like you'll never be dumb enough to design one of their parts into a
> product ever again?

If the company is mostly focused on one of the big markets, like automotive
or cell phones with short product lifecycles, there is a great change to run
into problems sometime later.

For propietary products Fujitsu is a no-go for me. And all the other
japanese/chinese too.


- Henry


--
www.ehydra.dyndns.info

On Sat, 09 Dec 2006 07:54:19 -0800, Tim Wescott <tim@seemywebsite.com> wrote:

>I am currently working with a client who is designing a PIC 
>microprocessor into his system.  It may be too late to change, but I am 
>being reminded of all the drawbacks to writing software for the PIC.
>
>I heard from a committed PIC booster that "yes, the architecture sucks 
>for programming, but the PIC never has delivery problems".  Choosing a 
>processor that my client couldn't get down the road would trump any pain 
>I may experience with less than beautiful code.
>
>Does anyone have experience with alternatives to the PIC (and 8051 
>derivatives) that show that this is not a problem?  The ones that come 
>to my mind the soonest are the AVR and the MSP430xxx lines, although I'm 
>sure that there are German and Japanese alternatives as well.  The story 
>I heard about delivery problems was specifically about "Atmel doesn't 
>understand that it's single-source".
>
>Thanks in advance.

If the client already uses the PIC, and you suggest another microcontroller.
Guess who gets the shaft if there are any problems...hehehe!

On Saturday, in article
     <KPCdnY4OvJCVNObYnZ2dnUVZ_v3inZ2d@web-ster.com>
     tim@seemywebsite.com "Tim Wescott" wrote:
>Paul Carpenter wrote:
>> On Saturday, in article
>>      <uY6dnVbOtoHWc-fYnZ2dnUVZ_rjinZ2d@web-ster.com>
>>      tim@seemywebsite.com "Tim Wescott" wrote:
>
>-- snip --
>
>>>But I do understand that you can't walk two feet without tripping over 
>>>an 8051.
>> 
>> My worry is how second sourced you want to be with everytime you turn around
>> and someone else's version runs on different voltages, pinouts, crystal
>> spec, clocks per cycle etc..
>> 
>> This applies to nearly ALL components. Amazing how many parts are actually
>> made in one batch and by the time most engineers have got to pre-production
>> manufacturer decided NOT to make anymore as they were not selling enough.
>> 
>I understand that if I want to use a microprocessor with peripherals 
>that I'm saying goodby to second source.  What I want is to know which 
>microprocessors companies have the best track records of taking care of 
>their single-sourced customers.

They are all companies, that just like us have finite resources, some have
different bias to sectors, there is *NO* magic solution (bar having the
complete raw materials silicon, gasses, metals to final product under
your own manufacturing control). The same as there is no magic technological
bullet that solves problems.

What ever company you deal with, will have problems at some time, even if
Microchip claim a 4week lead time at max, someone comes along and buys
most the stock of a particular part you want, will add a 4 week delay
if you hit that delay at the wrong time.

Some sectors like automotive, mean in a product lifecycle, you will still
be able to get the parts in 5 - 10 years time. I know of at least one
aviation sector project that has an obsolete part that they buy in as a
wafer, to then get packaged themselves, as the aircraft is still in
production!

If your volume is likely to be large talk early and often with your
distributor and manufacturer as this helps in production planning.
Who ever the manufacturer is.

My general rule is, when you are small volume try to ensure you have
product in your hand before laying out circuit, noting lead time and
ensuring you have parts in advance for at least the expected build
rate to cover lead time and review your requirements OFTEN.

-- 
Paul Carpenter          | paul@pcserviceselectronics.co.uk
<http://www.pcserviceselectronics.co.uk/>    PC Services
<http://www.gnuh8.org.uk/>              GNU H8 & mailing list info
<http://www.badweb.org.uk/>             For those web sites you hate

Tim Wescott wrote:

> But what I'm curious about is which companies have you had good 
> experiences with over the years, and which ones have left you feeling 
> like you'll never be dumb enough to design one of their parts into a 
> product ever again?

I would keep myself from Maxim. They make awesome ICs and they are 
really nice in providing the samples. However when it comes to the 
production quantities, you are stuck for the unknown time period.

VLV