I need to select the 8-bit microcontroller for Audio player. If I select one of the controllers, in which pins have to select for the Audio.
madhu.b 
Selection of Microcontroller
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madhu.b 
clawson 
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madhu.b I am talking about audio signal. The audio input signal which is coming from mike and in order to select the microcontroller and write the c programme for to get the audio output on the speakers.
bobgardner The mic signal needs to be amplified so that the peak to peak amplitude is about 5V. It also needs to be biased at 2.5V. An opamp preamp can do this job. The AVR a/d converter can take readings fast enough for speech quality, but not fast enough for hi quality music. If you use a mega1284 AVR with 16K of ram, you can only catch about 2 seconds of speech! To play it back, you can use a pwm output into an RC lowpass filter, but then you need an amplifier like an LM386 to drive an 8 ohm speaker.
jgmdesign 
Dumb question time......
Why do you need a micro controller to do this?:
Quote:
The audio input signal which is coming from mike and in order to select the microcontroller and write the c programme for to get the audio output on the speakers
You do not ned a micro to get audio from a mic to the speakers. Connect the mike to an amplifiers input and the speaker(s) to it's output(s)
TaDa, no c programming required.
clawson
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madhu.b
Are you talking about digitization so the audio can be recorded digitally? If so what sample rate are you hoping for? (which is kind of what I was asking in the first place!).
stevech we have a goal/skill ratio problem here.
valusoft 
?/0 = infinity
MBedder madhu.b wrote:
There is a plenty of IC's already preprogrammed for this functionality. People usually call them "audio amplifiers", thougth I can't guarantee they have been programmed in C.
I am talking about audio signal. The audio input signal which is coming from mike and in order to select the microcontroller and write the c programme for to get the audio output on the speakers.
krazatchu 
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?/0 = infinity
+1 Internets to you dear sir...
bobgardner Put your flame suits on ye naysayers. You are about to be taken to the woodshed Yet Again by Eric The Terrible. What part of Play Nice dont you guys understand?
leon_heller 
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One can do fun things with a DSP, like capturing samples and playing them backwards.
Xantor hcum pleh t'nseod sseleulc gnieb PO
ka7ehk
I think that there is a serious mismatch between what microcontrollers are good at, and what this project attempts to do.
IMHO, what madhu needs is just an old fashioned "audio amplifier". Why?
1. Anything that a micro can output will need an amplifier, anyway, to drive a speaker.
2. The OP has not given any desired features that could really benefit from conversion to digital and back to analog, again. Such features MIGHT include recording, frequency emphasis, and such. But, all that was given was microphone in and loudspeaker out. In this simple case, there is nothing that benefits from digital conversion.
Jim
bobgardner Nevertheless, up to now, the big bottleneck to using an AVR as an audio gizmo has been lack of ram. The RuggedCircuits 512K ram card for the mega arduino just about ends this problem.
leon_heller
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Why bother with that when 16-bit dsPICs with plenty of RAM and a lot more performance are available. Here is an old design of mine intended for amateur radio applications:
http://webspace.webring.com/peop...
I'm updating it with the newer 40 MIPS dsPIC33FJ128GP802 device - cheaper, smaller, and with a lot more RAM. It actually has a 12-bit ADC and a dual-channel 16-bit DAC, but I'm using a codec with it. It's available in 28-pin SDIP, which makes prototyping easy.
krazatchu Why bother with that when 32-bit ARMs with plenty of RAM and a lot more performance are available.
Oh, wait, isn't this the AVR forum?
leon_heller
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It's General Electronics!
dsPICs are easier to use than ARMs for this type of application, and will work out cheaper.
Here is a little single-sided board suitable for making at home that I've just designed:
http://www.leonheller.com/dsPIC/...
http://www.leonheller.com/dsPIC/...
Daughter boards with codecs, or microphone and speaker interfaces, can be plugged in to it.
Last Edited: Sun. Mar 4, 2012 - 07:33 PM
bobgardner Except Atmel doesnt make dspics, and you are just about to hit the ice that's Real Thin.
leon_heller
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Can you come up with an easier and cheaper way to do audio processing?
bobgardner Xmegas have 12 bit differential a/ds that run at pro sample rates and have dma, and they are made by Atmel, that for some reason still hasn't revoked your username for shilling for their competition. Knock it off and/or Get Lost.
krazatchu In addition to the Xmega, I'm looking forward to getting my hands on the new Arduino DUE. It rocks an ATMEL SAM3U, an ARM Cortex M3 clocking in at 96MHz...
I actually have an audio project in the pipeline for it.
Last Edited: Sun. Mar 4, 2012 - 08:53 PM
leon_heller
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The Xmega lacks DSP capability, and doesn't have a 16-bit DAC. It also lacks a codec I/F.
bobgardner You are just crusin for a brusin aren't you? Ever been to Yosemite with a big bag of marshmellows? Try it.
clawson
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On this occasion I have to side with Leon - he's not promoting a competitor product that's in direct competition to the Atmel product line. AFAIK Atmel don't produce small DSP micros and you would want to use a DSP for a DSP-centric job.
leon_heller
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They are unique devices. The only other small audio DSPs I know of are those from Wavefront:
http://www.wavefrontsemi.com/ind...
and they are rather difficult to use (I couldn't get them to work, anyway). There is a warning about not using them for new designs, perhaps they have stopped making them. They have never been all that popular.