pay_c Posted April 1, 2006 Report Share Posted April 1, 2006 Hi there!I guess that's some religious question, isn't it? ;DFor that reason I implemented a religious poll, too... ;)Following: I'm planning to do different projects, most of them require fairly high ADC rates and perhaps some complex programming. As I have little experience with the PIC ( ;D ;D ;D) I first thought I should stick to it, as the ADC rate is pretty high if maxed out (PIC16F appr. 50 kSamples/s possible, right?) and I won't have to learn THAT much more (still I'll be busy with that for a year, I think ;) ). On the other hand MANY DIY projects also use the AVR Mega Controllers as they are told to be easily programmable (Basic, Pascal, C, whatever) and the periphery is pretty inexpensive. Only the ADC rate is much lower (for highest 10 bit resolution appr. 15 kSamples/s). But as I only will need something around 7bit accuracy, I'm taking the advantage into account that I could make my programs within higher languages like C, so the programming effort would be brought down.Does ANYBODY have suggestions what the big differences are between PIC's and AVR's? What do you use besides MBHP-PIC's for your own projects and why?THNX in advance! Quote Link to comment Share on other sites More sharing options...
Wise Posted April 1, 2006 Report Share Posted April 1, 2006 Using ATMega8, 168, 32, 64 and 644 at work. Coding Basic with Bascom. Works for what we are doing (electonic control systems for pellet burners, electrical thermostates, oxygen sensor and that kind of stuf). Only problem now is long leadtimes on the atmega644 :( Quote Link to comment Share on other sites More sharing options...
TK. Posted April 1, 2006 Report Share Posted April 1, 2006 Today AVR should be the first choice, it has a modern architecture, and is easier to program.Unrelated to your question I would like to mention, why I still stick to the PICs: it wouldn't take much time to port MIOS and most of the applications to AVR, but the support effort would be much higher (supporting two different architectures is a mess), and benefit wouldn't be that high. The only candidate which could be used for the MBHP is ATMEGA644 (64k flash, 40 pin DIP), but it's hard to get (as Wise mentioned), and the datasheet says "not recommended for new designs". All newer devices with more than 32k flash are only available in a TQFP package - if I ever take the risk to provide a core module with SMD devices, I would prefer a much more advanced 16bit or 32bit microcontroller. Especially an option for fast accesses to external flash/SRAMs would be very appreciated for a more flexible graphical LCD handling.Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
stryd_one Posted April 1, 2006 Report Share Posted April 1, 2006 Not to mention that Microchip seem reluctant to fix certain silicone errors :\I would love to see a more advanced chip in a core module to replace the PIC18F... But I think that trying to support two different chips is definitely a bad idea. Maybe one day in the distant future the PIC18F will be superseded, but I think that for now it is doing OK - and if they ever do fix those silicone bugs, it will be much better. Quote Link to comment Share on other sites More sharing options...
Wise Posted April 1, 2006 Report Share Posted April 1, 2006 and the datasheet says "not recommended for new designs". Yiii ! Doesen't sound so good for us :-\ Know why ? Quote Link to comment Share on other sites More sharing options...
pay_c Posted April 1, 2006 Author Report Share Posted April 1, 2006 :o :-X :oNow I've really got to say that I'm most astouned about that for real! I could have sweared that at least *somebody* recommends to stick with PIC's, but that's some clear anouncement there. ... wow ...Hmmm, ok, so I'll check out the AVR's the next days. I think I'll stick to the ATMega 32 first, just because it has DIP packaging and for my first tries enough memory (I want to try to bring the whole map of a GLCD into the memory if possible. That's 1024 byte for a 128x64 GLCD - so the 2048 RAM should be enough). I also hope to bring up the ADC sampling frequency by downgrading the ADC to a 7-bit resolution. *Mathematically* I should come out @ appr. 100 kHz sampling frequency, which should *just* be enough hopefully. Let's see.More suggestions? Would love to see some "beginners" HP's or DIY stuff with the ATMega's to get a bit more of a clue.Perhaps I'll also get one of those famous "butterflies" to get an idea what the AVR's are capable of. Let's see. Quote Link to comment Share on other sites More sharing options...
moebius Posted April 1, 2006 Report Share Posted April 1, 2006 Ok,I say 'stay with the PICs' :D My only reasoning behind this: Microchip seems a bit more serious about supporting DIP packages than Atmel.Of course the future is SMD, but this is a major problem to some parties. I mean, Atmel gained it's reputation with Advanced 8051 derivates. When I was in the school we were using those - we did prototyping on 3rd party development boards. Whatever each person had as a project was supposed to be possible to "realize" in the real world. Logically (or being brand loyal) the school has moved to using AVRs, but what will the next step be when those are phased out?!?/rant offThese seems not to fit for your needs, but still: Former Scenix SX, Ubicom SX is still alive, now in the hands of the Parallax (the basic stamp fame) http://www.parallax.com/sx/chips.asp - PIC 16C5x compatible with speeds up to 75MHz (or even 80MHz overclocked ;))Moebius Quote Link to comment Share on other sites More sharing options...
pay_c Posted April 2, 2006 Author Report Share Posted April 2, 2006 Yeah, that's also some point. Ok, at least *some* chips will hopefully still be PLCC instead of TQFP (both AVR's and PIC's are offering PLCC-packaging stuff) so it still will be somewhat like DIY-compatible. I don't think that one day ALL will go to only-SMD stuff as the hobbyiest's market still has to be satisfied somehow (and I think they will!).I think I'll try AVR's as the DIY programming stuff is very cheap (appr. 5 Euros for a ISP module compatible to the AVR Studio software), there are LOTS of sample programs & projects out there (googled five minutes and found TONS of good stuff) and I already got some experience with C-programming AVR's (I went into robotics for a few months some time ago). *IF* it's bad anyhow I still can go back to PIC's - I will certainly not loose to much money and/or time.'I looked at those Parallax IC's you mentioned! Very interesting, only (for my stuff) the BIG drawback is that there's no ADC on there. Yes, you could put an external there, but that's again quite complicated I think. For "normal" apps the high speed is very interesting, hopefully they'll bring something out with some more stuff (RAM, ADC and so on).THNX to all! ;D Will let you know what's up (also planning a blog or somewhat like that for all that stuff). Quote Link to comment Share on other sites More sharing options...
Dave_Wheeler Posted April 2, 2006 Report Share Posted April 2, 2006 Hi Pay_c.I like both :) :). For me it depends very much on the use. Far all of my DIY targets I use PIC, yes they have their quirks but generally they do what it says on the label :) I also only code in asm. Some of this may be me being lazt as I have a good library that I have built up so 'most' things I want to do, I just grab some modules and bolt them together.At work I use all sorts of processors, It depends a lot on what is the best price at design time. I have used the baby 10 series PICs, AVR, AVR Mega, ARM core stuff and some other odd ball processors.I think what I am getting to is that it depends soooooooo much on the application. For example I have just completed an amateur TV 23cms repeater logic based on a single PIC, PIC chosen as easy for someone else to support. The ICD 2 is not a lot of money and makes debugging very easy, MPLAB is free. For some other processors the tools can be very expensive and you may still have limited debugging available. Of course if you write you code without any bugs and it always works first time then this will not matter :) :)Cheers,Dave Quote Link to comment Share on other sites More sharing options...
Wise Posted April 5, 2006 Report Share Posted April 5, 2006 The only candidate which could be used for the MBHP is ATMEGA644 (64k flash, 40 pin DIP), but it's hard to get (as Wise mentioned), and the datasheet says "not recommended for new designs". Have spoken to our Atmel sales representative and he sais that the M644 will be replaced by a m644p version, which will draw much less power. Therefore the note about new designs in the m644 datasheet. And Atmel has not released the datasheet for the p version on their website./wise Quote Link to comment Share on other sites More sharing options...
stryd_one Posted April 6, 2006 Report Share Posted April 6, 2006 I'd still rather a fixed silicone rev of the 4620 to a mega644.... Darn you, Microchip! FIX IT!!! :o[me=stryd_one]goes crazy [/me] Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.