Kinetis MicrocontrollersのトピックRe: HD Audio bus using I2S/SAI?

HD Audio bus using I2S/SAI?

bowerymarc — Wed, 10 Jul 2013 22:54:07 GMT

Has anyone worked out whether its possible, and have examples or source code etc. for interfacing an HD Audio type of Codec to a kinetis using the I2S/SAI port?

Example codecs: CODECs | WM8860 | Wolfson Microelectronics and CS4207 : Low Power 4-In/6-Out HD Audio Codec with Headphone Amp

Some great features on these kinds of parts for portable apps.

Thanks!
Marc

Re: HD Audio bus using I2S/SAI?

Paul_Tian — Thu, 11 Jul 2013 02:53:43 GMT

Hi, Marc

Standing on Kinetis point, there is only I2S interface between Codec and Kinetis. So you can refference this applicaton note for your application. In this applicaiton note, you can find it uses four FIFOs and Ping-Pong mode. http://cache.freescale.com/files/microcontrollers/doc/app_note/AN4520.pdf?fsrch=1&WT_TYPE=Application Notes&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation&sr=1

Hope my reply can help you.

Best Regards

Paul

Re: HD Audio bus using I2S/SAI?

bowerymarc — Thu, 11 Jul 2013 03:01:05 GMT

HI Paul,

Actually no, that's no help. I've seen that app note, and it doesn't address this. The I2S bus on the Kinetis is SAI, can be configured for many different formats aside from strictly I2S. So my question still remains, whether it's possible to configure this port to be compatible with HD Audio Codecs to the extent of basic functions like getting audio in and out, for example with the codecs linked above.

Best,

Marc

Re: HD Audio bus using I2S/SAI?

bowerymarc — Thu, 11 Jul 2013 05:09:33 GMT

well I read chapters 5 and 6 of the HD Audio spec (http://www.intel.com/content/dam/www/public/us/en/documents/product-specifications/high-definition-audio-specification.p…)

and it looks like it won't work, mainly due to the audio output being clocked on alternating edges of the bit clock, and the bit clock running at 24MHz, max for the Kinetis (otherwise, maybe could have run the SAI at double speed...)

Note for Freescale: consider adding HD Audio mode ability to the SAI peripheral!