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Per Westermark
06/21/10 16:41
Read: 762 times
Sweden


 
#176811 - Sales - "may be used for" presented as "recommended"
Responding to: Andy Neil's previous message
Yes. The important words are "some" and "may".

The manufacturers needs to do fishing - trying to present their products in a way that gains them the maximum number of customers (or at least the maximum number of sold units). That means that they are not always 100% truthful. If a processor "may" be used for a specific application, they will not inform a customer that a competitors product is actually much better suited for the task.

That's why it is so important to be critical, and to read the datasheets and not just application notes or sales material. Reading the datasheets gives us needed information to try and - at least in our heads - map the actual processor to the problem we have in front of us. But the task is hard, since we need to abstract away a lot of pesky details while at the same time not miss any show stoppers. We need to detect when a GPIO pin also have two alternative functions - functions that we need at the same time. We need to detect when the amount of code will be too large, or too slow. We need to detect if a peripherial is missing dual-buffering, or if activation of feature x will also push us above the required power budget.

The task is hard, but to be competitive, we must be able to browse 20 different chips, and then shortlist 2-4 candidates for closer examination. Even if one of our current processors can solve a problem with more or less tweaking, it may cost us too much to use it. Fighting lack of memory may delay shipments with weeks or months. Lack of I/O pins may cost us external multiplexer chips. Lack of configurability may cost us x mAh/day because we can't turn off a main oscillator while keeing an RTC running. Lack of availability may require the first redesign six months after initial shipments, or months of delays caused by lead times. Requiring 2.6V supply voltages just to manage the power budget may result in costly and space-consuming level shifters instead of having a different chip that manages the power consumption at 3.3V or 5V.

Neither of these things will be mentioned in the manufacturers sales information. The chip may be recommended for automotive use. But only when you buy the version with the extra letter in the name and the $1 higher price - but the price they initially show you is the "normal" consumer-grade chip. And they may tell that xxx only have 4 weeks lead times, but forgetting to mention that the xxxVX (the one with automotive classification) has 30 weeks lead time...

In the end, you'd like some good relations with some brand-neutral application engineers with access to prerelease information for new chips and access to the order systems.

In the end, it's hell on earth to do a good analysis, since no manufacturer or sales organisation is too interested in informing about weak spots.

List of 104 messages in thread
TopicAuthorDate
So What Is An 8051/2 Good For?      Andy Neil      06/17/10 16:35      
   thoughts      Erik Malund      06/18/10 04:36      
      The Future of the 805x      Joseph Hebert      06/18/10 08:40      
         PARC      Rob Klein      06/18/10 09:01      
            Bigger Hammers      Joseph Hebert      06/18/10 09:37      
               re: Bigger Hammers      Rob Klein      06/18/10 10:59      
               The opposite problem seems more common here!      Andy Neil      06/18/10 15:50      
         Would Toyota have had the problem if ...      Erik Malund      06/18/10 09:31      
            Toyota: Case in point      Joseph Hebert      06/18/10 09:46      
            RE: Toyota      Andy Neil      06/18/10 10:17      
               It was a mechanical fix ...      Richard Erlacher      06/18/10 22:37      
            Parallel Processing      Justin Fontes      06/18/10 10:35      
               Sometimes the practical reality is of little consequence      Richard Erlacher      06/18/10 22:45      
                  Totally Agree, but I was looking for a magic bullet      Justin Fontes      06/18/10 23:09      
                  RE: "outperform"      Andy Neil      06/19/10 01:10      
                     There are some operations ...      Richard Erlacher      06/19/10 06:19      
                        rephrased      Erik Malund      06/19/10 06:44      
                        Now, you are extrapolating      Per Westermark      06/19/10 06:44      
                           good points, but      Erik Malund      06/19/10 07:12      
                              How many 8051 chips uses 0.13u?      Per Westermark      06/19/10 08:57      
                                 not yet      Erik Malund      06/19/10 13:05      
                           not exactly ...      Richard Erlacher      06/20/10 09:39      
                              Do not get focused on one operation...      Michael Karas      06/20/10 10:20      
                              any 8-bit instruction can exist in a 32-bit processor      Per Westermark      06/20/10 12:14      
                                 Yes, but does it?      Richard Erlacher      06/22/10 07:54      
                                    So have you looked at any other processors?      Per Westermark      06/22/10 09:37      
                                       not a point of disagreement, but you missed it anyway      Richard Erlacher      06/22/10 22:50      
                                          A good point      Justin Fontes      06/22/10 23:10      
                                             beg to differ      Michael Karas      06/22/10 23:23      
                                             Disagree entirely!      Andy Neil      06/23/10 00:45      
                                          Yes, auto-increment/decrement is standard and not "feature"      Per Westermark      06/23/10 00:29      
                                             What I wanted to point out ...      Richard Erlacher      06/23/10 06:07      
                                                Same same all the time. no "one size fits".      Per Westermark      06/23/10 07:46      
                                                   and the most important point is (drumroll) ....      Erik Malund      06/23/10 09:49      
                                                Comparing Apples to Oranges      Andy Neil      06/23/10 08:03      
                                          Prices are comparable      Andy Neil      06/23/10 01:00      
               Parallel processing        Oliver Sedlacek      06/22/10 02:40      
                  Sweeping generalisation!      Andy Neil      06/22/10 03:22      
                     Not a magic silver bullit      Per Westermark      06/22/10 04:20      
                        Fond memories      Oliver Sedlacek      06/22/10 07:58      
                        A magic bullet      Justin Fontes      06/22/10 10:17      
                           Most concepts already exists in the wild      Per Westermark      06/22/10 11:31      
                           Another generalisation        Andy Neil      06/22/10 14:43      
                           Speed vs latency      Oliver Sedlacek      06/22/10 14:47      
                              Why 8051?      Andy Neil      06/22/10 15:08      
                                 Isn't it obvious?      Justin Fontes      06/22/10 23:17      
                                    ARM simpler than 8051      Oliver Sedlacek      06/23/10 00:21      
                                       Generalisation      Andy Neil      06/23/10 01:34      
                                          ARM 'MCUs' have their limitations too!      Valentin Angelovski      06/24/10 07:52      
                                             You normally engineer with a backup plan      Per Westermark      06/24/10 08:20      
                                    No, it's not!      Andy Neil      06/23/10 01:27      
                                       Im just trying to provide an argument      Justin Fontes      06/23/10 10:33      
                                          x bits are just one parameter among many      Per Westermark      06/23/10 11:27      
                                             Avoiding the issue      Justin Fontes      06/23/10 21:09      
                                                Avoiding what issue?      Per Westermark      06/24/10 03:10      
                                          They say it because it's true!      Andy Neil      06/24/10 00:59      
                                          RE: ARM is not the only 32-bitter      Andy Neil      06/24/10 01:15      
                                    Please don'g generalize      Per Westermark      06/23/10 01:28      
                                 Heterogenous multiprocessing widespread      Oliver Sedlacek      06/23/10 00:17      
                  Re: Multicore 8051      Valentin Angelovski      06/24/10 06:48      
                     ALU chaining      Oliver Sedlacek      06/24/10 06:57      
   Well... maybe      Jez Smith      06/18/10 14:47      
      A Linear Accelerator?      Joseph Hebert      06/18/10 15:28      
         Its one of these      Jez Smith      06/18/10 15:51      
      please, repeat      Stefan KAnev      06/19/10 04:56      
         All I was saying was      Jez Smith      06/19/10 10:39      
   So what the '51 are good for...      Jan Waclawek      06/21/10 13:54      
      Not terribly helpful      Andy Neil      06/21/10 14:46      
         Always up to the developers      Per Westermark      06/21/10 15:24      
            RE: The manufacturers tells us...      Andy Neil      06/21/10 15:30      
               Sales - "may be used for" presented as "recommended"      Per Westermark      06/21/10 16:41      
               pretty hot, low-power and small      Maarten Brock      06/22/10 15:17      
                  Automotive...      Andy Neil      06/22/10 15:26      
         but answers your original question (at least the one...      Jan Waclawek      06/22/10 10:19      
         MCS51 still rocking !!!      Kiran V. Sutar      06/23/10 05:14      
            Scale      Andy Neil      06/23/10 06:09      
            Missing the point      Andy Neil      06/23/10 06:21      
               Impossible to generalize into fields      Per Westermark      06/23/10 08:09      
                  An appropriate generalisation...      Andy Neil      06/23/10 10:20      
               You are right..Andy Neil      Kiran V. Sutar      06/24/10 05:27      
                  Cheers!      Andy Neil      06/24/10 05:43      
                     No..only AT89C52 can be used      Kiran V. Sutar      06/24/10 05:56      
                        why do you insist on Atmel?      Erik Malund      06/24/10 06:05      
                        what a strange post      Erik Malund      06/24/10 06:09      
                        Tools?      Andy Neil      06/24/10 07:12      
                           Multiple manufactuers with (almost) identical chips      Per Westermark      06/24/10 07:48      
                              Getting better      Andy Neil      06/24/10 08:52      
                                 Unified interrupt controller is really great      Per Westermark      06/24/10 09:28      
                           Yes, even with free tools for PIC/AVR      Kiran V. Sutar      06/24/10 08:38      
                              I mean no offense, but ...      Richard Erlacher      06/26/10 09:59      
                              Similar difficulties coming to 8051/2?      Andy Neil      06/26/10 10:28      
                                 Same same      Per Westermark      06/26/10 11:18      
                  Is it your purchase price or why so sure AVR or PIC are off?      Per Westermark      06/24/10 05:55      
                     Answer to Per and Erik...      Kiran V. Sutar      06/24/10 06:38      
                  Living in the past      John D. Maniraj      06/24/10 09:44      
                     Thanks John D. Maniraj      Kiran V. Sutar      06/25/10 03:54      
                     locking      Erik Malund      06/25/10 07:20      
                        RE: Locking      Andy Neil      06/25/10 07:32      
                        Agreed, but      John D. Maniraj      06/25/10 11:00      
                           fairly easy      Erik Malund      06/25/10 11:53      
      Don't forget consumer devices      David Good      06/24/10 13:45      
         A perfect application      David Good      06/25/10 10:49      
   8051 vs ARM      Valentin Angelovski      06/24/10 08:34      
   just thought of one case      Erik Malund      06/24/10 12:32      

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