at the end of this huge mail:


On Tue, 29 Jan 2002, myke predko wrote:

> > Hi all
>
> Hi Mahmood!
>
> > We are all great fans of the pic, I'm trying to use the PIC16F877 for a
> > project, my boss is forcing me to use 8051, I need 30 I/O lines
> > including 2 serial ports and eeprom space where my F877 fits perfectly.
> > I searched through most of the 8051 family but couldn't do it with a
> > single chip.
>
> As people have pointed out, if you are willing to look at different versions
> of the 8051, you can find something that will fit your I/O needs.
>
> > He argues that the pic has awkward architecture with small memory map
> > and poor support for compilers. Looking at the F877 I think it's the
> > opposite, it has large memory and a great architecture and lots of
> > peripherals and 2 fast, there are also lots of good compilers around.
>
> You later put in:
>
> > I already had a big fight with him over other things, don't want to make
> > it any bigger, he gave me an 8051 biased application note to read about
> > how to chose a microcontroller its at
> >
> www.egr.msu.edu/classes/ece482/Reports/appnotes/98spr/tsaimelv/appnote.html
> > I already showed him on paper the difference between the 2 but I think
> > the real reason he refuses is that he never used a pic before in his
> > life. And also that appnote might be comparing PIC16C54 to the 8051
> > family which is unfair.
>
> > Any suggestions, comments, feedback welcome.
>
> First off, I would consider the 8051/8052 MCU to have two clear advantages
> over the PIC16F877:
>
> 1.  If you have to add eight bit peripherals to your application, the
> 8031/8051/8052 chips are superior in this regard.  I have put in 8 bit I/O
> devices on PIC17C4x's, but these are more expensive and do not have Flash
> program memory.
>
> 2.  The 8051 can run an RTOS more efficiently than the PIC16F877.  The
> PIC18C/Fxxx give the PICmicro MCU similar capabilities, but they don't have
> the ICD of the PIC16F877.
>
> Where the PIC16F877 has a clear advantage is in regard to ICD coupled with
> MPLAB - for a low cost in-circuit debugging solution, I do not believe that
> there is a comparable 8051 product.  You could argue that a debugger written
> for the 8051 could be used similarly, but you wouldn't get all the features
> of ICD and certainly not the source code level interface of MPLAB/ICD.
>
> As others have pointed out, the web page your boss has pointed has a number
> of significant inaccuracies (I wouldn't call them biases because I saw some
> pretty outrageous things said for all the devices).  Looking at my 1982
> Intel datasheets, it's interesting to note that Intel calls the 8051 a "RISC
> device".  Where I would go back to your boss is noting that the page is 4
> years old.  Devices like the PIC16F877 did not exist when the page was
> created.
>
>
> What you didn't indicated is what you are designing and how many are going
> to be built.  I think the PICmicro MCU has an advantage in terms of
> development tool cost and availability.  Microchip has done a very nice job
> with MPLAB, PICSTART Plus, PICMASTER, MPLAB ICE, and so on along with
> enabling compiler writers and tool vendors.  8051 vendors have not been so
> proactive and have made available the breadth and quality of the tools
> available for the PICmicro MCU.
>
> My gut feeling is that feature for feature, you can get a PIC16F877 cheaper
> than a comparable '51.  But...
>
> You never know when somebody's going to find a skid of parts in a warehouse
> that are available for a nickel on a dollar - if this has happened in the
> past, you'll probably get told of that quite a bit.  You can, however, note
> that Digi-Key has chosen the PICmicro MCU as their primary line and really
> have done a lot to support the different devices and make sure the prices
> are good and supply is consistent.  Look at companies like Future-Active
> (that carries both the PICmicro MCU and 8051 part numbers) and see what the
> prices are like.
>
>
> If I were in your position, I would first really try to understand why your
> boss is insisting on using the 8051.  Does he have a relationship with a
> company/supplier?  Is he your boss because he made a home run in the company
> using the 8051?  Are there any other emotional reasons why he would insist
> on the 8051?
>
>
> If it comes down to ignorance about the PICmicro MCU with no strong
> emotional baggage associated with the 8051, you can make the following
> statements noting:
>
> 1.  That since you are going to be developing the application in a HLL, so
> the processor architecture is irrelevant.
>
> 2.  You are not going to require the features of the 8051 that clearly
> differentiate it from the PICmicro MCU.
>
> 3.  You can get much better development tools for a given amount of money
> (ie $1K USD will get you a "C" compiler integrated into MPLAB along with ICD
> and probably enough money left over for a PICSTART Plus).  I *know* you
> can't get comparable 8051 tools for this amount of money.  Depending on your
> company's size, you will probably be able to expense rather than make
> capital purchases for PICmicro MCU development tools, which avoids a lot of
> hassles for your boss.
>
> 4.  You feel that over the long term, you will be able to get consistently
> get parts with superior pricing on the PICmicro than on the 8051.  In terms
> of parts availability, I have never heard anything bad about Philips
> (although I have heard complaints about other 8051 manufacturers) and
> Microchip is always very good (except for their habit of announcing products
> before they're able to ship good silicon).  Look at different distributor's
> web pages and print out quantity pricing for 100, 1,000 and 10,000 units for
> vendors that sell both architectures.
>
>
> Don't get into arguments over which architecture is better - I can come up
> with convincing arguments that the 8051 is better and then come up with a
> similar number of arguments that the PICmicro is better.  The four points
> above are pretty unemotional and hard to debate.
>
>
> As somebody already noted, at the end of the day, your boss is still your
> boss, so if he insists on the 8051, it's probably in your best interest to
> go with the 8051.
>
> Good luck.
>
> Comments on this from anybody else?
>
  Mike, as you know better, to comment is much easy than to do,
so because I have an ugly problem with SPI on 877 I prefer to delay the
moment when I must begun my work...
I have started with PICs in the moment I already knew a lot of things
about 8051. Mostly because PICs are better represented on the internet.
I'm talking about "how to do" and code examples. The presence of
http://www.piclist.com and of many other guy's websites, who decide to
share own work was essential for me.
For fun PIC is probably the best, for production I have doubts.
About Reduced Instruction Set Computer, I think neither PIC or 8051 does
not represent a good RISC arhitecture.
So, nothing new on the face of the earth...
regards, Vasile

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