design an embedded system with ac6905a bluetooth IC [closed]

You're trying to build an embedded system with a variety of peripherals. There is a general approach that might prove helpful, which I'll try to share a bit, but your question is really far too broad to get any meaningful answer.

First, break your design into modules. For example, you have a central processor, a bluetooth IC, and a microphone. You also need to pay attention to some of the peripherals on your microcontroller, which would be the A/D to capture the microphone, the memory where the data from the microphone is going, the bus that you're using to talk to the bluetooth unit, possibly your interrupt controller on the microcontroller. You also need to consider any user interfaces, like on/off buttons, indicator lives, a button to turn the microphone on.... You also need to think about any interface circuitry you might need, like analog amplification and conditioning of your mic signal.

Draw block diagrams of how all these modules will be interacting with each other. This will uncover some surprises, but is well worth doing.

Now that you've figured out how all these things go together, it's time to divide and conquer. Figure out how you can implement and test each aspect of your design ALONE, without any of the other parts. The idea is to get each part working alone, then put them together one piece at a time, testing at each stage. Where there is too much interconnectivity to separate, make sure that one part is as bulletproof as you can make it before incorporating it into a bigger system.

Next, you develop your sandbox. What pieces and tools do you need to play with things? Are there evaluation kits for the parts you need to use that might make design easier. If not, you might consider a more accessible part. Do you have a bluetooth receiver that will interface with the device you're trying to build. How much memory do you think you need? What development kit are you planning on using? What processor family are you comfortable with, and where are you likely to find help and support if you need it?

After doing all this, Now, you can make your purchases and build.

I should say the pre-first step should be figuring out if a solution exists already. There are obviously systems that you can buy that will take the output of a microphone and send it out over bluetooth audio. You should figure out if they meet your needs.

Obviously, if you modularize all this correctly, it isn't necessarily a serial process. You can do parts in parallel, or work one module to near completion, or begin your assembly before dealing with some of the aspects you don't think you have trouble with. Just DON'T be tempted to put off something in your critical path to success, thinking "I'll work that out later", unless you have solid experience that can support that decision.