Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
Jason Arkwright
12/18/10 07:43
Read: 1360 times
Chester
U.k.


 
#180195 - AVR update
Responding to: Erik Malund's previous message
Hi All,

Sorry I havent been around lately but I've been playing around with the ATMEGA644 PDIL40, first in line is the integral 10 bit adc, it's basically crap, in differential free running interrupt mode, it will only work with a Vref of >2V and the input mux suffers badly from channel to channel crosstalk, only in free run mode though, if the mcu invokes a conversion then no crosstalk occurs however this mode ties up the mcu which waits for the conversion to complete and then returns a result.The manufactures claim that the adc differential mode is not guaranteed on the PDIL40?, and the input gain opamp is restricted to 4kHz bandwidth.

Later, I hooked up the MCP3302, programmed in differential mode and works beautifully, gives +-4095 counts with a Vref of 1.5V Vref works down to 1V!

Here's the kicker, the AVR ATMEGA644 works happily with a 30MHz crystal giving a 30 mips throughput, the chip does not crash and is stable.
Inconjunction with the MCP3302 adc, it can sample at >50kHz(single channel), thats 13 bits, eh? more than enough for some DSP applications.

The other point I would wish to raise is the bit handling capabilities of the AVR instruction set are crap, for example, with the '51 you can send the carry flag directly to any port pin, you can't do this with AVR which makes assembler bit banging routines complicated.
However, from a maths point of view, the AVR reigns supreme over the '51.

Cheers for now
JA



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      

Back to Subject List