audio Codec AK4556

spa23 · ‎2015-10-19

Posted on October 19, 2015 at 20:55

Hi uguys

I seemsto have a small problem, I'm trying to send and receive some audiodata to a external codec, the codec is an AK4556.

I usethe cubeMx to initialize the I2S.

When I look at the signals.

Everything looks fine except the data from the codec (SD EXT), I'm sending in a line signal audio to the analog in, and now I want the analog signal to be converted and send back to the STM32, that would be nice, but nothing happens the pin just stays low :(

So does any one haveexperience with thees type of code, so they can help me in the rightdirection, you help is highly appreciated Thank.

PS:when sending data to the codec, the analog out is “moving�?.

waclawek.jan · ‎2015-10-19

Posted on October 19, 2015 at 22:38

Set the data-receive (SDext) pin to GPIO input. Still no signal? Is the CODEC properly reset as per datasheet? Does the pin-selected mode match the mode (clocks mutual ratio) set in STM32? Is MCLK output properly (the waveform you posted shows intermittent MCLK but I understand it can be the sampling limitation of the LA you are using). Still no signal? Then check connections, recheck twice, measure directly from pin to pin, check if not connected to adjacent pins/tracks inadvertently. Check power lines and grounds. Cut track next to Tx pin of CODEC if needed. Still no signal? Can't the CODEC be damaged?

JW