EVAL-ADAU1467Z GPIO set up question (basics and confusions)
Ahoy. I'm having trouble generally parsing some parts of the documentation that refer to each other all over the place and aren't really that clear.
At any rate, since the sample rate for the graph block seems to be too slow to actually visually show things like zero-crossing detection with any accuracy, I want to output the result of the crossing detection circuit to a GPIO pin and monitor it with a CRO. I'm at a loss as to which pins I can actually use and where they're accessible on the board.
One of the documentation points says that MP12 is on Header J3, Pin 4 - J3 appears to only have 3 pins. So you see my confusion there.
And the documentation on the Multipurpose tab of the Hardware Configuration is either lacking or convoluted. I would appreciate some help setting up this basic MP output.
Cheers
~David
Bump.
Hello David,
In another post I did mention that the graphing function reads too slowly for things that happen on a sample by sample basis. So you have to use counters and timers and things like that to capture some of these events. Going out to a GPIO is also good as you mentioned.
I have a couple of programs I put together a few years ago that does some counting and zero cross counting etc. I will attach them here. Might give you some ideas.
6281.ADAU1452 Period Calculation using zero Cross.zip4810.ADAU1452 Sample period counter with reset and pulse counter.zip
Regarding the eval board. I think there have been some revisions so this might be some of the confusion. I did not design this one or maintain it. I do have this schematic which shows that MP12, which has the main function of LRCLK_IN2, is connected directly to the codec. There are no headers that it goes to but there is a test point. The only problem will be if the codec is set to be a master but I think it is set to be a slave so you should be able to use it if you like.
Here is the schematic I am using.
Dave T
Thanks for the schematic, I'll see how I go with it. I got derailed onto other projects but I'm back to this one now - will probably have more questions.
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