help for audio codec using VHDL

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i am a begineer at using altera DE2 board and VHDL. i have to complete my project with in 10 days time but dont have any idea of where to start and how.. help .........

i need to build a duplex audio system that works similar to a phone but here CDMA must be considered.

first i would like to have some good advice on where to start and how .... on audio CODEC

any help would be more than appreciated

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I have attached a few pieces of my hardware description in VHDL. Note that is for the Wolfson WM8731 on the DE1 board. But the DE2 has the same chip so the attached hardware description should work with the appropriate pin assignment modifications.

Note that I could not upload clockBuffer.vhd because of the 5 file limit. BUT you should be able to easily create the clockBuffer using the MegaIP wizard. Also I do not claim my code is the best (especially the i2c part) but it does the job.

You should go through the code and understand how it works. Honestly, if you are a beginner with VHDL and DE2, it may be very difficult to finish this project in 10 days (unless you have previous hardware design experience).

Good luck.

Bart

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would you please upload it with the whole project .... that would be of great help... please zip all the project file and upload it........... that would be helpful... anyways than you for your update

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Hey,

My project will not help you because I don't have a DE2 board (yet). Anyway, I have attached the final .vhd file (clockBuffer). You should simply be able to create a new Quartus project, import pin assignments for the DE2 and modify the top-level accordingly.

Again IMO, if you have difficulty migrating my project from the DE1 to DE2 board, finishing a CDMA design in 10 days might be very difficult.

Bart

this is the pin table i just cant find the right pin for the names you have defined........ the board keeps playing sound irrespective of the program..... i dont know what to do ........ even if i get this done it would be great achievement leave alone the CDMA part.... i might use HDLC frame format instead but currently i need to manipulate the audio input. ...... and since the system is to be full duplex using nios is not the solution...... would you help me in pin assignment .............that would of great help

cheers

thanks again for replying

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i tried it with your program it just gives a silent output i couldnt get the mic in output using it can you suggest why is that happening???

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The comments at the beginning of my top-level says that my hardware does only Line-In to Line-Out loopback.

If you want to use the Mic, then you have to modify the i2c initialization routine. It is actually simple to do. Read the audio codec datasheet (it should be on your DE2 CD), specifically starting at page 46 where it describes the register map. Figure out the exact register you need to program for mic in.

Good luck.

Bart

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The code should be published at the Altera Wiki. It's much more instructive than the respective Terasic demonstration projects.

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Thanks for the tip. I am creating a website which will have reference designs from our school and was going to post a link to it on these forums. But, I will publish this code and others at Altera wiki as well (once I have cleaned them up a bit).

Have a great week.

Bart