Audio codec shield with Intel Edison

[guest]

that code may not work, depending upon how youve defined the variables, it might lose the sign bit (which sounds like crackling). a good test is to create a signed 16b integer, and increment its value by 1 each time you write to the codec. the output should look like a saw tooth wave. if it does not, the shape it forms can tell you something about where the error is occuring (as longs as its not just noise). the frequency is really low at a +1 increment, so try +100 if youre not probing the DC coupled output (or just want to listen to it).

[youthreewire]

[guest]

sure, i can give it a try, but it might be a while. did you have any luck getting it working on your end?

also, how long a "nop" is, is hardware dependent. on some platforms it might make the SPI too fast.

[youthreewire]

Thanks. Please give it a try.

I am running the code on Arduino Due which is overclocked at 96 mhz. So as you rightly said nop will introduce different timing. You will be needing an oscilloscope that can measure in nano seconds (my scale was that one division on the scope was 200 nanoseconds long).I tried changing the values to match with the hardware spi that I got to work on the Due.

I will wait for the results from your end on the software SPI. You know better about timing.

Here is the link to the original software SPI .

[guest]

do you have a complete sketch i can test? im not sure what 'b' or msk[] are referring to.

[youthreewire]

I will give you the sketch and I think as you said I should test with an unsigned 8 bit integer.I will get back to you shortly.

[youthreewire]

[guest]

what failure mode do you see with this code?

a couple of things to note:

1. you can not send audio data over the serial comm, the audio data rate is too high
2. hardware spi is still being setup with codec.h, which is probably conflicting with direct port manipulation.

[youthreewire]

I know that the audio data cannot be sent over the serial port. Also I just made this sketch for you.I was using an ARDUINO Due and since you had atmega328 I just wrote this code up.Feel free to modify as you want it.

I also created a 6 MBPS transfer rate on the Due but still it had some delay.

[guest]