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Erik Malund
12/22/10 18:22
Read: 1214 times
Mt Airy, Nc
USA


 
#180244 - hogwash
Responding to: Jason Arkwright's previous message
it's so easy to overclock an AVR device because of it's single clocking architecture.I've already explained that the '51 requires special design proceedures to overclock given it clocks at either 12 or 6 division xtal clocks
hogwash first overclocking is NOT a parameter. Second the ability to handle a given clock speed has ansolutely nothing to do with divided clock or non-divided clock.

so 30MHz equates to 5 mips, crystals above 30MHz are usually 3rd harmonic which don't oscillate nicely, so a drop in crystal above 30MHz is hard to come by, this is not the case with the AVR.
many newer '51' s have PLLs

Sililabs produce nice chips but they are both expensive and difficult to prototype owing to their smd only package.
High speed and DIL gives some really nice reflections

The other point I wish to stress, is that output port pins on the '51 are normally common source with pull ups on their respective , they reach their limits very sharpish at 5 mips, i.e., looking at the waveforms communicating with a serial 13 bit a/d dont look good, much healthier waveforms can be seen from the AVR, doing the same job, which use the standard DDR in/out format.
hogwash a)many (even <$1) derivatives (e.g. the LPCs) of the '51 have configurable ports b) the quasi-bidirectionals have the "short hard pullup" which gives you very nice Waveforms unless you insist on crappy layout.

I have no problem with you using AVRs but do not accept that you promote them with false and/or unreliable statements.

Erik

List of 103 messages in thread
TopicAuthorDate
Migrating to AVR      Jason Arkwright      12/06/10 10:02      
   8051-replacement      Andy Neil      12/06/10 11:37      
      Yep, I agree      Jason Arkwright      12/06/10 13:47      
         Toolchain      Andy Neil      12/06/10 14:41      
            free compilers      Jason Arkwright      12/06/10 15:32      
               GCC      Andy Neil      12/07/10 00:24      
               Free ARM compilers      Oliver Sedlacek      12/07/10 07:14      
                  "Free" vs "Free"      Andy Neil      12/07/10 07:54      
   faster '51 derivatives in DIL/PLCC & availability      Jan Waclawek      12/06/10 13:26      
      Tired of hanging around with 5 mips      Jason Arkwright      12/06/10 14:04      
         Re: Tired of hanging around with 5 Mips      Valentin Angelovski      12/06/10 17:59      
            experiences prototyping with smd's      Andy Neil      12/07/10 00:09      
               Prototype SMD      Oliver Sedlacek      12/07/10 09:24      
            Nice, but where to buy and how much?      Jason Arkwright      12/07/10 04:57      
               Re: where to buy and how much?      Valentin Angelovski      12/07/10 07:48      
                  Yeah, but....      Jason Arkwright      12/07/10 08:36      
                     I agree      Valentin Angelovski      12/07/10 17:11      
                        re the XA      Erik Malund      12/08/10 06:39      
                     How many 51' compilers make use of the 51's dual DPTR      Andy Neil      12/07/10 17:54      
               You must live on a very interesting corner!      Andy Neil      12/07/10 07:55      
                  Ha,ha, AVR are ubiquitus      Jason Arkwright      12/07/10 08:22      
                     HUH??      Erik Malund      12/07/10 08:36      
                        Lies, Damned Lies, and Statistics      Andy Neil      12/07/10 09:08      
                           I think      Erik Malund      12/07/10 12:01      
                        'F120      Andy Peters      12/07/10 10:36      
                           "bunchload"      Andy Neil      12/07/10 11:35      
                              re: bunchload      Andy Peters      12/08/10 09:28      
                                 Youse guys in Old Blightly        Andy Neil      12/08/10 10:04      
         Prototyping SMD's      John D. Maniraj      12/07/10 00:58      
            Hand-made PCBs with hand-soldered SMDs      Andy Neil      05/04/11 08:30      
            SMD's      Jerry Hudson      05/08/11 09:24      
               Well, that's nice, but not necessary.      Richard Erlacher      05/09/11 09:42      
            a very general - and accurate - comment ...      Erik Malund      05/11/11 07:14      
               apprehension      Andy Neil      05/11/11 07:33      
   nearby      JecksonS Ben      12/07/10 22:12      
      'jumping' from the '51      Erik Malund      12/08/10 06:52      
         AVR update      Jason Arkwright      12/18/10 07:43      
            the chip does not crash      Andy Neil      12/18/10 11:34      
               Lockup etc      Per Westermark      12/18/10 13:41      
                  increase the clock until lockup      Jason Arkwright      12/18/10 15:50      
                     undefined behaviour      Andy Neil      12/18/10 16:24      
                     NO, they do not recommend it      Erik Malund      12/18/10 16:27      
                        simultaneous posts      Erik Malund      12/18/10 16:28      
                           Overclocking        Per Westermark      12/19/10 04:30      
                     This is simply an error in judgment        Richard Erlacher      12/19/10 09:38      
                        all bets are off      Andy Neil      12/20/10 01:19      
                     overclocking        Andy Peters      12/22/10 09:27      
                        Yeah, okay      Jason Arkwright      12/22/10 10:31      
                           Neeed for speeed      Andy Neil      12/22/10 10:56      
                              Because of this...      Jason Arkwright      12/22/10 16:55      
                                 Missing the point      Andy Neil      12/22/10 17:16      
                                    missing the point?      Jason Arkwright      12/22/10 17:46      
                                       Modern derivatives      Andy Neil      12/23/10 01:02      
                                 hogwash      Erik Malund      12/22/10 18:22      
                                 I'm not sure you're on track here ...      Richard Erlacher      12/22/10 20:39      
                                    Hi Richard      Jason Arkwright      12/23/10 14:44      
                                       the problem with AVR's is that they're ATMEL only      Richard Erlacher      12/25/10 08:59      
                                          That's one general and one personal problem      Andy Neil      12/26/10 12:08      
                                             Yes, that's what it is ...      Richard Erlacher      12/26/10 19:29      
                                                Second source not so important anymore      Per Westermark      12/27/10 07:40      
                                                   It's not as convenient now as it once was      Richard Erlacher      12/27/10 08:01      
                                                      Free tools only have investment in knowledge      Per Westermark      12/27/10 08:29      
                                                         again. Per      Erik Malund      12/27/10 09:04      
                                                            Not at all      Per Westermark      12/27/10 09:46      
                                                         it's not just the tools      Richard Erlacher      12/27/10 14:44      
                                                            "Best code"        Per Westermark      12/28/10 05:56      
                                                               There are too many definitions of "best"      Richard Erlacher      12/28/10 15:47      
                                                               Don't go for best      Steve M. Taylor      01/03/11 08:50      
                                                   yes and no      Erik Malund      12/27/10 08:29      
                                                   Single-source chips vs single-source architecture      Andy Neil      12/27/10 10:23      
                                 cross purposes      Andy Peters      12/23/10 11:12      
                                    DSP PROCS      Jason Arkwright      12/23/10 14:25      
                                       gp ahead, stay behind the curve      Erik Malund      12/23/10 14:37      
                                          Got to disagree there,...      Jason Arkwright      01/02/11 15:55      
                                             I do not consider 'luck' a design parameter      Erik Malund      01/03/11 05:24      
                                             Flying leads      Valentin Angelovski      01/03/11 05:33      
                                       re: DSP PROCS        Andy Peters      12/27/10 10:48      
                           100MHz 32-bit ARM      Per Westermark      12/22/10 12:49      
                              The Trap...      Jason Arkwright      12/22/10 17:11      
                                 talking out of both sides of the mouth      Erik Malund      12/22/10 18:27      
                                 "on the DSP level"        Andy Neil      12/23/10 01:07      
                                    Often hand-optimized assembler available      Per Westermark      12/23/10 07:59      
                                    Misunderstood me      Jason Arkwright      12/23/10 16:14      
                                       Cross talk      Per Westermark      12/23/10 16:37      
                                       What kind      JecksonS Ben      12/23/10 18:19      
                                       nobody has suggested      Erik Malund      12/24/10 10:11      
                           no, you are not      Erik Malund      12/22/10 14:59      
                           there are '51s with MACs      Erik Malund      12/22/10 15:05      
                              and...      Andy Neil      12/22/10 16:21      
                                 yes and      Erik Malund      12/22/10 18:28      
                                 He wants Plastic Dips      Neil Kurzman      12/22/10 18:28      
                                    very few and      Erik Malund      12/22/10 18:33      
                                    the 33 mips DS89C450 is in DIP if you want      Richard Erlacher      12/22/10 20:42      
            no such thing as "Best"      Andy Neil      12/18/10 11:38      
               '51 weaknesses outweigh the AVR      Jason Arkwright      12/18/10 16:02      
                  similiar      JecksonS Ben      12/18/10 21:07      
                  Quite so      Andy Neil      12/19/10 08:59      
                     3, 4, 5        Michael Karas      12/20/10 08:25      
                        Horses for courses      Andy Neil      02/14/11 01:22      
                  Have you considered using a DSP?      Richard Erlacher      05/11/11 16:55      
   I'll be off too, but not to AVR      Oliver Sedlacek      02/14/11 03:31      
      A Guess      Michael Karas      05/04/11 18:54      
         Low volume      Oliver Sedlacek      05/05/11 06:25      

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