Posted on April 25, 2014 at 14:13My recollection of I2S is that it comes from the CD player chipsets and DACs, where left/right channels were shifted as a continuous stream 16-bit left/right channel and the WS indicating which channel was being sent, and providing synchronization.
It has been subsequently bastardized into other formats (to avoid patent/licensing issues and litigation), including apparently mono PCM streams, bit direction, stuffing in random bits, and being of random bit lengths and coding schemes. These would be PCM formats, that some codecs can generate or source, but are technically serial sound formats, not I2S. Controllers offering I2S, may also be configurable in other ways.
Pretty sure the STM32 will work with CD/DVD audio codecs and dacs, but it's definitely not sufficiently flexible for Telco audio formats, or codecs that invent their own standards.
