SAI_cfg_t Struct Reference

Complete configuration structure for the SAI driver. More...

#include <sai.h>

Public Attributes
uint32_t	txClkFreq {12288000}
uint32_t	rxClkFreq {12288000}
rxTxSync_t	rxTxSync {RXTX_ASYNC}
I2S_Type *	sai
SAI_rxtx_cfg_t	rx
SAI_rxtx_cfg_t	tx

Detailed Description

Complete configuration structure for the SAI driver.

This structure encapsulates all configuration parameters for both the transmit and receive channels of the SAI peripheral, along with shared parameters like clock frequencies and synchronization mode.

Clock Configuration

Clock frequencies determine the sample rate:

• Sample Rate = Clock Frequency / (bits per word x words per frame)
• Common audio rates: 8kHz, 16kHz, 44.1kHz, 48kHz, 96kHz

Example for 48kHz stereo 24-bit:

• Clock = 48000 x 24 x 2 = 2,304,000 Hz

Usage

For most applications, use one of the predefined configurations:

• SAI_I2S_SLAVE_24_TXRX_RK: I2S slave, 24-bit, full duplex, RX clock
• SAI_LJUST_SLAVE_16_TXRX_TK: Left-justified slave, 16-bit, TX clock

Or customize from a base configuration:

SAI_cfg_t myConfig = SAI_I2S_SLAVE_24_TXRX_RK;
myConfig.txClkFreq = 3072000;  // Adjust clock for 16kHz sample rate
myConfig.rx.enable = false;     // Transmit only

Member Data Documentation

rx

SAI_rxtx_cfg_t SAI_cfg_t::rx

Receive channel configuration

rxClkFreq

uint32_t SAI_cfg_t::rxClkFreq {12288000}

Receive bit clock frequency in Hz. Default: 12.288 MHz

rxTxSync

rxTxSync_t SAI_cfg_t::rxTxSync {RXTX_ASYNC}

Synchronization mode between RX and TX channels

sai

I2S_Type* SAI_cfg_t::sai

Pointer to the SAI hardware instance (SAI1, SAI2, or SAI3)

tx

SAI_rxtx_cfg_t SAI_cfg_t::tx

Transmit channel configuration

txClkFreq

uint32_t SAI_cfg_t::txClkFreq {12288000}

Transmit bit clock frequency in Hz. Must match the actual clock rate for proper operation. Default: 12.288 MHz (512 x 48kHz for 24-bit stereo)

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The documentation for this struct was generated from the following file:

• sai.h