PIC vs AVR vs ARM
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From: Isaac Bosompem on 4 Oct 2006 16:58 Ulf Samuelsson wrote: > > > * snip * > > I did also read the tutorial but I didn't read through all of it. > > Eclipse is damn terrible, consumes a large amount of memory (seriously, > > on my system it consumes almost as much physical memory as that FEAR > > game) and is very slow. > > I attended an Eclipse Seminar, and 1GB RAM is minimum > and many need 2 GB to run properly. 1GB minimum?! haha, not even my games( circa late 2005 games too!) need that much RAM! Well that is the amount of RAM I have in my system. -Isaac
From: Ulf Samuelsson on 4 Oct 2006 18:20 > Disclaimer: I don't work for Atmel or Arm, just unbiased opinions. > <Troll> Disclaimer, I work for Atmel and have unbiased opinions :-) </Troll> -- Best Regards, Ulf Samuelsson This is intended to be my personal opinion which may, or may not be shared by my employer Atmel Nordic AB
From: rickman on 5 Oct 2006 08:38 Ulf Samuelsson wrote: > "rickman" <gnuarm(a)gmail.com> skrev i meddelandet > news:1159903397.463883.11040(a)k70g2000cwa.googlegroups.com... > > We have used AVR MCUs in many of our products and were very happy with > > them. On a new project I decided to take a look at the ARM MCUs to see > > if we could branch out from some of the limitations of the AVR. We did > > a very exhaustive comparison between the various ARM processors and the > > ATmega128 and found that the ARM chips were generally lower power, > > lower cost and fit in a smaller footprint on the board. We also were > > able to use a much smaller crystal. > > When power is an issue, you typically have to spend as much > time as possible in sleep mode, and the Picopower AVR > will be at least an order of magnitude better than the AT91SAM7 here. And whether this is significant depends on the application. The AVR could be ten orders of magnatude better than the ARM in sleep mode, but if the active mode power is 90% of your power budget, the sleep mode will not have much of an impact on total power. As I said, depending on your application this may be important. If you are designing a data logger where it is asleep for two weeks and then is triggered to record something for a few seconds, sleep mode power may be important. But this is a very small percentage of applications. > Also, when running from an R/C oscillator you can turn on/off almost > instantly, > while the AT91SAM7 probably have to start the PLL which will take ~16 ms. > One drawback of Picopower is that the startup time from sleep > is increased from a few clock cycles to about 70 us. > This is the time it takes to activate the brownout detector which is > disabled in deep sleep. > (Don't worry, the part is protected from Brown-Out by the Power On Reset in > deep sleep) And the R/C oscillator is only useful in a small percentage of applications where you don't need any more timing precision than what is required to run a UART, and just barely that! > I think the PicoPower AVR is therefore hard to beat when you really need low > power. Yep, in the small percentage of apps where you need the unique features of an 8 bit MCU tailored to low power when it is not running, then it can do a good job. But most MCU apps run the MCU a fair percentage of the time if not 100%. In those apps the power is dominated by the active current and the ARM can beat the AVR there.
From: Vladimir Vassilevsky on 5 Oct 2006 09:53 rickman wrote: > > As I said, depending on your application this may be important. > My experience is that it does not really matter which core to select. All brands offer approximately same performance for the similar price. What does matter when selecting the MCU is if it has the peripherals needed by the application. ARMs are mainly the CPUs rather then the MCUs. AVR peripherals are only fair. PIC peripherals are great, albeit the PIC core is disgusting. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
From: Everett M. Greene on 4 Oct 2006 22:39
"Ulf Samuelsson" <ulf(a)a-t-m-e-l.com> writes: [snip] > > I did also read the tutorial but I didn't read through all of it. > > Eclipse is damn terrible, consumes a large amount of memory (seriously, > > on my system it consumes almost as much physical memory as that FEAR > > game) and is very slow. > > I attended an Eclipse Seminar, and 1GB RAM is minimum > and many need 2 GB to run properly. Good gawd, Gertie! What were the implementors using for brains (presuming they had any)? The bloated size and user testimonial above indicates that the implementors have the intelligent level of a rock. |