The I2S module provides a standardized
serial interface to transfer audio samples between the CC13x2x7 and
CC26x2x7
device platform and the external audio devices (such as a codec, DAC, or ADC).
The I2S module can also receive pulse density modulation (PDM) signals from devices (such as digital microphones) followed by conversion to pulse code modulation (PCM) in software.
The I2S module has the following features:
- Audio clock signals are internally generated by the PRCM module or externally by another device.
- One or two data pins, which can be configured independently as input or output
- I2S, left-justified (LJF), and right-justified (RJF) serial interface formats that support up to two audio channels per data pin
- DSP serial interface format that supports up to eight audio channels per data pin
- Up to 24-bit sample word length, with truncation or zero-padding if not matching:
- Serial interface: 8 to 24 bits per sample word, most significant bit (MSB) transferred first
- Memory: 16 or 24 bits per sample word, stored in little-endian byte order
- DMA with double-buffered pointers
- Error detection for DMA and audio clock signal integrity
- A Samplestamp generator that allows maintaining
of constant audio latency when audio samples are
produced by the I2S module on one CC13x2x7 or CC26x2x7 device and consumed by the
I2S module on another CC13x2x7 or CC26x2x7 device.