[SOLVED] AVR & pic & ARM difference ?

[h.galeh]

I see, there are many kinds of microcontrollers used nowadays
PIC , AVR , ARM , FPGA,DSP,CPLD,...
as a newcommer ,really whats the difference between these micro's?
I think ARM is a more complete micro but why do we use PIC or AVR
please guide me through appliance of each one

 

[yura717]

I think to answer your question it will takes hours .... if you just start learning microcontrollers than learn first PICs

 

[yongee]

There're 2 sites that will answer your question: Google.com and Wikipedia.org

I'd say just pick AVR or PIC and start learning...

 

[h.galeh]

Re: AVR & pic & ARM difference ?

I think to answer your question it will takes hours .... if you just start learning microcontrollers than learn first PICs

I mean where do we use AVR while PIC is unable to function . in other words whats the profession of each chip ?

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[FoxyRick]

There are too many overlapping criteria in many cases to give you a simple answer.

The simpler PIC and AVR chips are quite similar in capabilities and often the choice is simply personal preference. Both are designed with more I/O control capabilities than actual processing power. PIC32 are newer though and have a 32 bit MIPS core that is much more capable if you need faster processing. dsPIC has additional DSP logic in the core. Small PICs and AVRs are simple to develop for and are cheap.

ARM is a 32-bit RISC core and is generally used where you need far more processing capability than the simpler PIC and AVR chips can manage. For instance, running a small graphics-based tablet or a broadband modem/router. The downsides include being more complicated to develop for and more expensive.

DSPs are MCU's with additional, mathematical logic built in the core to allow much faster processing of linear/digitised signals. With such devices it is possible to make real-time digital filters and perform such things as FFT. While all of this could be done in software on standard MCU's, that is usually too slow to be useful.

CPLDs and FPGAs are not MCUs. They are programmable/configurable logic. Think of them as a few tens, up to millions, of programmable logic cells, with latches, gates and sometimes memory that can have all of the interconnections made and re-made by a design. CPLDs are smaller and used to replace a lot of logic chips on a board. FPGAs go up to HUGE (and huge cost!) and are big enough to design a whole microprocessor inside to interact with the rest of the logic. They are amazing!

 

[h.galeh]

There are too many overlapping criteria in many cases to give you a simple answer.

The simpler PIC and AVR chips are quite similar in capabilities and often the choice is simply personal preference. Both are designed with more I/O control capabilities than actual processing power. PIC32 are newer though and have a 32 bit MIPS core that is much more capable if you need faster processing. dsPIC has additional DSP logic in the core. Small PICs and AVRs are simple to develop for and are cheap.

ARM is a 32-bit RISC core and is generally used where you need far more processing capability than the simpler PIC and AVR chips can manage. For instance, running a small graphics-based tablet or a broadband modem/router. The downside is that they are more complicated to develop for and are more expensive.

DSPs are MCU's with additional, mathematical logic built in the core to allow much faster processing of linear/digitised signals. With such devices it is possible to make real-time digital filters and perform such things as FFT. While all of this could be done in software on standard MCU's, that is usually too slow to be useful.

CPLDs and FPGAs are not MCUs. They are programmable/configurable logic. Think of them as a few tens, up to millions, of programmable logic cells, with latches, gates and sometimes memory that can have all of the interconnections made and re-made by a design. CPLDs are smaller and used to replace a lot of logic chips on a board. FPGAs go up to HUGE (and huge cost!) and are big enough to design a whole microprocessor inside to interact with the rest of the logic. They are amazing!

thank you
I want to make a device which use adc to convert input audio signals
then I want to process each input frequencies of voice in digital vision . for example I want to remove low frequencies and just pass high frequencies
which one of the above devices is more perfect
I want to program voice due to its frequencies

 

[FoxyRick]

OK, so you want to do DSP. Depending on your exact requirements, you could use a standard MCU running at a fast clock speed, or a basic DSP chip, or something much faster. I'm going to have a guess (and it really is just a guess) that you could probably do what you want with a dsPIC. There are many code libraries and examples for it.

What sample rate, what bit depth, how many channels, how many filters (or even fft) do you need? Really, you have to decide on exactly what you need to do, work out the basics of the processing (filter topology, clock cycles to perform the transformation at your required rate, etc), then from that you can estimate the hardware requirements.

Possibly the best approach for you is to search the web for a similar project to your own.

 

[h.galeh]

Re: AVR & pic & ARM difference ?

what sample rate do you think is required to digitalize a clear voice?

 

[etmabreu]

Re: AVR & pic & ARM difference ?

what sample rate do you think is required to digitalize a clear voice?

Telephone systems are usually limited to 3kHz passband, 8kHz sampling rate, 8 bit quantification. Reasonable, recognizable, but not hi-fi.
A traditional CD player will have at least 16kHz passband, 44.1kHz sampling rate and 16 bit quantification.

 

[yura717]

what sample rate do you think is required to digitalize a clear voice?

If you want to work with DSP.... than first step you should learn mathematics and Matlab.

 

[jeffrey samuel]

First hit hard on some books my pal

the most basic of sampling questions is the rate it is given by Nyquist rate of sampling which is greater than twice that of the maximum frequency of the signal to be sampled . this will remove alaising as well as give a little head room frequency for the signal sampled

 

[h.galeh]

First hit hard on some books my pal

the most basic of sampling questions is the rate it is given by Nyquist rate of sampling which is greater than twice that of the maximum frequency of the signal to be sampled . this will remove alaising as well as give a little head room frequency for the signal sampled

what about its "bit"s

 

[FoxyRick]

h.galeh, seriously, you need to do some proper reading of how DSP works. It's not rocket science, but there are many things you need to know and understand, in order to understand properly any serious advice we can give you.

 

[jeffrey samuel]

that depends on the need you are fullfilling my pal hit some books hard