前面简单讲解了WM8960语音芯片工作方式,WM8960做master,之前参数配置ADC/DAC采样速率的是44.1K,有点问题,现在改为16K,下面会解释为什么要改成16K。
WM8960参数配置如下:注意录音时关掉内部路径,否则会有杂音。
#ifdef ALOOPBACK //先关掉内部路径播放 0x2d,0x080, //Left Input Boost Mixer to Left Output Mixer 0x2e,0x080, //Right Input Boost Mixer to Right Output Mixer #endif
//WM8960 slave mode // MCLK = 24MHz, SYSCLK = 12.288MHz, // PLL mode is fractional, MCLK div 2 const u16 wm8960_reg_master[]= { 0x0f,0x000, 0x19,0x17e, 0x1a,0x1e1, 0x2f,0x03c, 0x34,0x038, 0x35,0x031, 0x36,0x026, 0x37,0x0e6, 0x04,0x0dd, //ADC/DAC 采样速率12.288/(3*256) = 16KHz 0x08,0x00c, 0x20,0x138, 0x21,0x138, 0x2b,0x000, 0x2c,0x000, 0x00,0x157, 0x01,0x157, 0x05,0x000, 0x06,0x000, 0x07,0x042, //bit6=1, Enable master mode; bit[1:0]=10,I2S Format;bit[3:2]=00,16 bits 0x18,0x004, 0x30,0x000, 0x02,0x163,//179,// //LOUT1 Volume 0x03,0x163,//0x179,//ROUT1 Volume #ifdef DLOOPBACK //不开LOOPBACK 0x09,0x001, #endif 0x22,0x100, //Enable Left DAC to Left Output Mixer 0x25,0x100, //Enable Right DAC to Right Output Mixer #ifdef ALOOPBACK //先关掉内部路径播放 0x2d,0x080, //Left Input Boost Mixer to Left Output Mixer 0x2e,0x080, //Right Input Boost Mixer to Right Output Mixer #endif };
调用I2C函数进行初始化:
uint8_t WM8960_Set_Play_Recorde_Reg(void) { uint8_t i = 0; uint8_t res = 0; res = WM8960_Write_Reg((uint8_t)wm8960_reg_master[0], wm8960_reg_master[1]); if(res != 0) { return res; } Delay_ms(10); for(i=2; i<(sizeof(wm8960_reg_master)/sizeof(u16)); i+=2) { res = WM8960_Write_Reg((uint8_t)wm8960_reg_master[i],wm8960_reg_master[i+1]); } return 0; }
I2C发送函数,使用的是IO模拟:
void W8960_IIC_Init(void) { RCC->AHB1ENR|=1<<1; //使能PORTB时钟 GPIO_Set(GPIOB,PIN6|PIN7,GPIO_MODE_OUT,GPIO_OTYPE_PP,GPIO_SPEED_50M,GPIO_PUPD_PU);//PB10/PB11设置 W8960_IIC_SCL=1; W8960_IIC_SDA=1; // GPIO_InitTypeDef GPIO_InitStructure; // RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE); /* 打开GPIO时钟 */ // GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7; // GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; // GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT; // GPIO_InitStructure.GPIO_OType = GPIO_OType_OD; /* 开漏输出 */ // GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; // GPIO_Init(GPIOB, &GPIO_InitStructure); W8960_IIC_Stop(); } //产生IIC起始信号 void W8960_IIC_Start(void) { W8960_SDA_OUT(); //sda线输出 W8960_IIC_SDA=1; W8960_IIC_SCL=1; Delay_us(8); W8960_IIC_SDA=0;//START:when CLK is high,DATA change form high to low Delay_us(8); W8960_IIC_SCL=0;//钳住I2C总线,准备发送或接收数据 } //产生IIC停止信号 void W8960_IIC_Stop(void) { W8960_SDA_OUT();//sda线输出 W8960_IIC_SCL=0; W8960_IIC_SDA=0;//STOP:when CLK is high DATA change form low to high Delay_us(4); W8960_IIC_SCL=1; Delay_us(4); W8960_IIC_SDA=1;//发送I2C总线结束信号 Delay_us(4); } //等待应答信号到来 //返回值:1,接收应答失败 // 0,接收应答成功 uint8_t W8960_IIC_Wait_Ack(void) { uint8_t ucErrTime=0; W8960_SDA_IN(); //SDA设置为输入 W8960_IIC_SDA=1;Delay_us(5); W8960_IIC_SCL=1;Delay_us(5); while(W8960_READ_SDA) { ucErrTime++; if(ucErrTime>250) { W8960_IIC_Stop(); return 1; } } W8960_IIC_SCL=0;//时钟输出0 return 0; } //产生ACK应答 void W8960_IIC_Ack(void) { W8960_IIC_SCL=0; W8960_SDA_OUT(); W8960_IIC_SDA=0; Delay_us(4); W8960_IIC_SCL=1; Delay_us(4); W8960_IIC_SCL=0; } //不产生ACK应答 void W8960_IIC_NAck(void) { W8960_IIC_SCL=0; W8960_SDA_OUT(); W8960_IIC_SDA=1; Delay_us(2); W8960_IIC_SCL=1; Delay_us(2); W8960_IIC_SCL=0; } //IIC发送一个字节 //返回从机有无应答 //1,有应答 //0,无应答 void W8960_IIC_Send_Byte(uint8_t txd) { uint8_t t; W8960_SDA_OUT(); W8960_IIC_SCL=0;//拉低时钟开始数据传输 Delay_us(1); //发送前7bit,SCL下跳后1us才输出新SDA for(t=0;t<7;t++) { W8960_IIC_SDA=(txd&0x80)>>7; txd<<=1; Delay_us(4); // W8960_IIC_SCL=1; Delay_us(5); W8960_IIC_SCL=0; Delay_us(1); } //发送最后1bit,SCL下跳后无任何延时,后直接进入waitAck (SDA变输入,防止短暂SDA互斥) W8960_IIC_SDA=(txd&0x80)>>7; Delay_us(5); // W8960_IIC_SCL=1; Delay_us(5); W8960_IIC_SCL=0; } void W8960_I2C_WriteByte(uint8_t DevAddr, uint8_t DataAddr, uint8_t DataToWrite) { W8960_IIC_Start(); //Master发送起始信号 W8960_IIC_Send_Byte(DevAddr); //Master发送从设备地址 W8960_IIC_Wait_Ack(); // if(I2C_Wait_ACK()) return I2C_TIMEOUT;//等待ACK超时错误 W8960_IIC_Send_Byte(DataAddr); //发送数据地址 W8960_IIC_Wait_Ack(); // if(I2C_Wait_ACK()) return I2C_TIMEOUT;//等待ACK超时错误 W8960_IIC_Send_Byte(DataToWrite); W8960_IIC_Wait_Ack(); Delay_us(10); W8960_IIC_Stop(); //发送停止信号 Delay_us(10); } void W8960_I2C_WriteBurst(uint8_t DevAddr, uint8_t DataAddr, uint8_t* pData, uint32_t Num) { uint32_t i = 0; W8960_IIC_Start(); //Master发送起始信号 W8960_IIC_Send_Byte(DevAddr); //Master发送从设备地址 W8960_IIC_Wait_Ack(); W8960_IIC_Send_Byte(DataAddr); //发送数据地址 W8960_IIC_Wait_Ack(); for(i = 0; i < Num; i++) { W8960_IIC_Send_Byte(*(pData+i)); //发送数据 W8960_IIC_Wait_Ack(); } W8960_IIC_Stop(); //发送停止信号 Delay_ms(1); } //读1个字节,ack=1时,发送ACK,ack=0,发送nACK uint8_t W8960_I2C_Read8bit(uint8_t ack) { unsigned char i,receive=0; W8960_SDA_IN();//SDA设置为输入 for(i=0;i<8;i++ ) { W8960_IIC_SCL=0; Delay_us(4); W8960_IIC_SCL=1; receive<<=1; if(W8960_READ_SDA)receive++; Delay_us(4); } if (!ack) W8960_IIC_NAck();//发送nACK else W8960_IIC_Ack(); //发送ACK return receive; } void W8960_I2C_ReadBurst(uint8_t DevAddr, uint16_t DataAddr, uint8_t* pData, uint32_t Num) { uint32_t i = 0; W8960_IIC_Start(); //Master发送起始信号 W8960_IIC_Send_Byte(DevAddr); //Master发送从设备地址 W8960_IIC_Wait_Ack(); // W8960_IIC_Send_Byte(DataAddr>>8); //发送数据地址 // W8960_IIC_Wait_Ack(); W8960_IIC_Send_Byte(DataAddr); //发送数据地址 W8960_IIC_Wait_Ack(); W8960_IIC_Stop(); Delay_us(10); W8960_IIC_Start(); //Master发送起始信号 W8960_IIC_Send_Byte(DevAddr+1); //Master发送从设备读地址 W8960_IIC_Wait_Ack(); for(i = 0; i < (Num-1); i++) { *(pData+i) = W8960_I2C_Read8bit(1); //读数据,ACK } *(pData+i) = W8960_I2C_Read8bit(0); //读数据,NACK W8960_IIC_Stop(); //发送停止信号 } uint8_t WM8960_Write_Reg(uint8_t reg, uint16_t dat) { uint8_t tmp_H; uint8_t tmp_L; tmp_H =(uint8_t) (reg<<1)|((uint8_t) ((dat>>8)&0x0001)); //取高字节 tmp_L =(uint8_t) (dat&0x00FF); //取低8字节 W8960_IIC_Start(); //Master发送起始信号 W8960_IIC_Send_Byte(WM8960_IIC_ADDR); //Master发送从设备地址 if(W8960_IIC_Wait_Ack()==1) {return 1;}; //等待超时返回1 failed W8960_IIC_Send_Byte(tmp_H); //发送数据 if(W8960_IIC_Wait_Ack()==1) {return 1;}; //等待超时返回1 failed W8960_IIC_Send_Byte(tmp_L); //发送数据 if(W8960_IIC_Wait_Ack()==1) {return 1;}; //等待超时返回1 failed W8960_IIC_Stop(); //发送停止信号 return 0; }
I2C发送函数,使用的是STM32库函数:
i2c.h
#ifndef __I2C_H #define __I2C_H #include "stm32f4xx.h" #define I2C_LIB 1 #define DCMI_TIMEOUT_MAX 10000 #define DEVICE_WRITE_ADDRESS 0x34 #define DEVICE_READ_ADDRESS 0x35 /* Configure I2C1 pins: PB6->scl and PB7->sda */ #define Open_I2Cx I2C1 #define Open_i2c_CLK RCC_APB1Periph_I2C1 #define Open_i2c_SDA_PIN GPIO_Pin_7 #define Open_i2c_SDA_GPIO_PORT GPIOB #define Open_i2c_SDA_GPIO_CLK RCC_AHB1Periph_GPIOB #define Open_i2c_SDA_SOURCE GPIO_PinSource7 #define Open_i2c_SDA_AF GPIO_AF_I2C1 #define Open_i2c_SCL_PIN GPIO_Pin_6 #define Open_i2c_SCL_GPIO_PORT GPIOB #define Open_i2c_SCL_GPIO_CLK RCC_AHB1Periph_GPIOB #define Open_i2c_SCL_SOURCE GPIO_PinSource6 #define Open_i2c_SCL_AF GPIO_AF_I2C1 #define I2C_SPEED 60000 //WM8960 I2C clk must 60KHz #define I2C_SLAVE_ADDRESS7 0xFE void I2C_GPIO_Config(void); uint8_t I2C_Write_Byte(uint8_t Reg, uint8_t Data); #endif
i2c.c
#include "i2c.h" #include "stm32f4xx_i2c.h" void I2C_GPIO_Config(void) { GPIO_InitTypeDef GPIO_InitStructure; I2C_InitTypeDef i2c_InitStructure; RCC_AHB1PeriphClockCmd(Open_i2c_SDA_GPIO_CLK | Open_i2c_SCL_GPIO_CLK,ENABLE); RCC_APB1PeriphClockCmd(Open_i2c_CLK,ENABLE); GPIO_PinAFConfig(Open_i2c_SDA_GPIO_PORT, Open_i2c_SDA_SOURCE, Open_i2c_SDA_AF); GPIO_PinAFConfig(Open_i2c_SCL_GPIO_PORT, Open_i2c_SCL_SOURCE, Open_i2c_SCL_AF); GPIO_InitStructure.GPIO_Pin = Open_i2c_SDA_PIN | Open_i2c_SCL_PIN; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_OType = GPIO_OType_OD; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; GPIO_Init(GPIOB, &GPIO_InitStructure); I2C_DeInit(Open_I2Cx); i2c_InitStructure.I2C_Mode = I2C_Mode_I2C; i2c_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2; i2c_InitStructure.I2C_OwnAddress1 = I2C_SLAVE_ADDRESS7; i2c_InitStructure.I2C_Ack = I2C_Ack_Enable; i2c_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; i2c_InitStructure.I2C_ClockSpeed = I2C_SPEED; I2C_Init(Open_I2Cx, &i2c_InitStructure); I2C_Cmd(Open_I2Cx, ENABLE); I2C_AcknowledgeConfig(Open_I2Cx, ENABLE); } uint8_t I2C_Write_Byte(uint8_t Reg, uint8_t Data) { uint32_t timeout = DCMI_TIMEOUT_MAX; /* Generate the Start Condition */ I2C_GenerateSTART(Open_I2Cx, ENABLE); /* Test on I2C2 EV5 and clear it */ timeout = DCMI_TIMEOUT_MAX; /* Initialize timeout value */ while(!I2C_CheckEvent(Open_I2Cx, I2C_EVENT_MASTER_MODE_SELECT)) { /* If the timeout delay is exeeded, exit with error code */ if ((timeout--) == 0) return 0xFF; } /*-----------------------------------------------------------------------------------*/ /* Send DCMI selcted device slave Address for write */ I2C_Send7bitAddress(Open_I2Cx, DEVICE_WRITE_ADDRESS, I2C_Direction_Transmitter); /* Test on I2C2 EV6 and clear it */ timeout = DCMI_TIMEOUT_MAX; /* Initialize timeout value */ while(!I2C_CheckEvent(Open_I2Cx, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)) { /* If the timeout delay is exeeded, exit with error code */ if ((timeout--) == 0) return 0xFF; } /*-----------------------------------------------------------------------------------*/ /* Send I2C2 location address LSB */ I2C_SendData(Open_I2Cx, (uint8_t)(Reg)); /* Test on I2C2 EV8 and clear it */ timeout = DCMI_TIMEOUT_MAX; /* Initialize timeout value */ while(!I2C_CheckEvent(Open_I2Cx, I2C_EVENT_MASTER_BYTE_TRANSMITTED)) { /* If the timeout delay is exeeded, exit with error code */ if ((timeout--) == 0) return 0xFF; } /*-----------------------------------------------------------------------------------*/ /* Send Data */ I2C_SendData(Open_I2Cx, Data); /* Test on I2C2 EV8 and clear it */ timeout = DCMI_TIMEOUT_MAX; /* Initialize timeout value */ while(!I2C_CheckEvent(Open_I2Cx, I2C_EVENT_MASTER_BYTE_TRANSMITTED)) { /* If the timeout delay is exeeded, exit with error code */ if ((timeout--) == 0) return 0xFF; } /*-----------------------------------------------------------------------------------*/ /* Send I2C2 STOP Condition */ I2C_GenerateSTOP(Open_I2Cx, ENABLE); /* If operation is OK, return 0 */ return 0; }
这里有个问题,I2C 时钟频率只能设置在60K,设置高点、低点,播放时就会有噪声,让人费解。
WM8960 I2C初始化函数 uint8_t WM8960_Set_Play_Recorde_Reg(void),注意这函数里有个数据格式转换,可以查看WM8960 I2C 传输格式,
地址寄存器有效为是7位[bit15 : bit9],数据有效为是9位[bit9 : bit0],但是发送的时候,是按照一个字节8bit发送的,先发地址寄存器7位 [bit15 : bit9]还得带上
数据位的最高bit8,构成[bit15:bit8]一个字节,所以数据得转换一下:
temp = sizeof(wm8960_reg_master)/sizeof(u16); for(i=0 ; i<temp; i+=2) { WM8960_Reg_Config[i] = ((uint8_t)(wm8960_reg_master[i]<<1)) | ((uint8_t)((wm8960_reg_master[i+1]>>8)& 0x01)); WM8960_Reg_Config[i+1] = (uint8_t)(wm8960_reg_master[i+1] & 0xff); }
#define REG_NUM 100 uint8_t WM8960_Reg_Config[REG_NUM] ={0}; void Data_Format_Convert(void) { uint8_t i = 0; uint8_t temp = 0; temp = sizeof(wm8960_reg_master)/sizeof(u16); for(i=0 ; i<temp; i+=2) { WM8960_Reg_Config[i] = ((uint8_t)(wm8960_reg_master[i]<<1)) | ((uint8_t)((wm8960_reg_master[i+1]>>8)& 0x01)); WM8960_Reg_Config[i+1] = (uint8_t)(wm8960_reg_master[i+1] & 0xff); } } uint8_t WM8960_Set_Play_Recorde_Reg(void) { uint8_t i = 0; uint8_t res = 0; #ifdef I2C_LIB Data_Format_Convert();//对WM890的数组寄存器数据进行转换 res = I2C_Write_Byte(WM8960_Reg_Config[0],WM8960_Reg_Config[1]); if(res != 0) return res; Delay_ms(10); for(i=2; i<(sizeof(wm8960_reg_master)/sizeof(u16)); i+=2) { res = I2C_Write_Byte(WM8960_Reg_Config[i],WM8960_Reg_Config[i+1]); } #else res = WM8960_Write_Reg((uint8_t)wm8960_reg_master[0], wm8960_reg_master[1]); if(res != 0) { return res; } Delay_ms(10); for(i=2; i<(sizeof(wm8960_reg_master)/sizeof(u16)); i+=2) { res = WM8960_Write_Reg((uint8_t)wm8960_reg_master[i],wm8960_reg_master[i+1]); } #endif return res; }
重点讲解下I2S的DMA方式及注意事项:
(1)、首先是I2S 管脚定义:
/** * I2S×ÜÏß´«ÊäÒôƵÊý¾Ý¿ÚÏß * WM8960_LRC -> PB12/I2S2_WS * WM8960_BCLK -> PB13/I2S2_CK * WM8960_ADCDAT -> PB14/I2S2ext_SD * WM8960_DACDAT -> PB15/I2S2_SD * WM8960_MCLK -> PC6/I2S2_MCK */ /* Enable GPIO clock */ void WM8960_I2S_GPIO_Config(void) { GPIO_InitTypeDef GPIO_InitStructure; RCC_AHB1PeriphClockCmd(WM8960_LRC_GPIO_CLK|WM8960_BCLK_GPIO_CLK| WM8960_ADCDAT_GPIO_CLK|WM8960_DACDAT_GPIO_CLK| WM8960_MCLK_GPIO_CLK, ENABLE); GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; GPIO_InitStructure.GPIO_Pin = WM8960_LRC_PIN; GPIO_Init(WM8960_LRC_PORT, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = WM8960_BCLK_PIN; GPIO_Init(WM8960_BCLK_PORT, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = WM8960_MCLK_PIN; GPIO_Init(WM8960_MCLK_PORT, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = WM8960_DACDAT_PIN; GPIO_Init(WM8960_DACDAT_PORT, &GPIO_InitStructure); GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; GPIO_InitStructure.GPIO_Pin = WM8960_ADCDAT_PIN; GPIO_Init(WM8960_ADCDAT_PORT, &GPIO_InitStructure); /* Connect pins to I2S peripheral */ GPIO_PinAFConfig(WM8960_LRC_PORT, WM8960_LRC_SOURCE, WM8960_LRC_AF); GPIO_PinAFConfig(WM8960_BCLK_PORT, WM8960_BCLK_SOURCE, WM8960_BCLK_AF); GPIO_PinAFConfig(WM8960_ADCDAT_PORT, WM8960_ADCDAT_SOURCE, WM8960_ADCDAT_AF); GPIO_PinAFConfig(WM8960_DACDAT_PORT, WM8960_DACDAT_SOURCE, WM8960_DACDAT_AF); GPIO_PinAFConfig(WM8960_MCLK_PORT, WM8960_MCLK_SOURCE, WM8960_MCLK_AF); }
(2)、配置I2S 发送,STM32做的从机,所以不需要配置MCLK,当然也不需要输出:
void WM8960_I2Sx_Mode_Config(const uint16_t _usStandard,const uint16_t _usWordLen,const uint32_t _usAudioFreq) { I2S_InitTypeDef I2S_InitStructure; #if 0 //STM32作为从机不需要配置时钟 uint32_t n = 0; FlagStatus status = RESET; /** * For I2S mode, make sure that either: * - I2S PLL is configured using the functions RCC_I2SCLKConfig(RCC_I2S2CLKSource_PLLI2S), * RCC_PLLI2SCmd(ENABLE) and RCC_GetFlagStatus(RCC_FLAG_PLLI2SRDY). */ RCC_I2SCLKConfig(RCC_I2S2CLKSource_PLLI2S); RCC_PLLI2SCmd(ENABLE); for (n = 0; n < 500; n++) { status = RCC_GetFlagStatus(RCC_FLAG_PLLI2SRDY); if (status == 1)break; } #endif /* 打开 I2S2 APB1 时钟 */ RCC_APB1PeriphClockCmd(WM8960_CLK, ENABLE); /* 复位 SPI2 外设到缺省状态 */ SPI_I2S_DeInit(WM8960_I2Sx_SPI); /* I2S2 外设配置 */ /* 配置I2S工作模式 */ I2S_InitStructure.I2S_Mode = I2S_Mode_SlaveTx;//I2S_Mode_MasterTx; /* 接口标准 */ I2S_InitStructure.I2S_Standard = _usStandard; /* 数据格式,16bit */ I2S_InitStructure.I2S_DataFormat = _usWordLen; /* 主时钟模式 */ I2S_InitStructure.I2S_MCLKOutput = I2S_MCLKOutput_Disable;//I2S_MCLKOutput_Enable; /* 音频采样频率 */ I2S_InitStructure.I2S_AudioFreq = _usAudioFreq; I2S_InitStructure.I2S_CPOL = I2S_CPOL_Low; I2S_Init(WM8960_I2Sx_SPI, &I2S_InitStructure); /* 使能 SPI2/I2S2 外设 */ I2S_Cmd(WM8960_I2Sx_SPI, ENABLE); SPI_I2S_DMACmd(WM8960_I2Sx_SPI,SPI_I2S_DMAReq_Tx,ENABLE);//SPI2 TX DMA请求使能. }
(3)、配置I2S接收模式,配置双缓冲模式
void WM8960_I2Sxext_Mode_Config(const uint16_t _usStandard, const uint16_t _usWordLen,const uint32_t _usAudioFreq) { I2S_InitTypeDef I2Sext_InitStructure; /* I2S2 外设配置 */ RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE); /* 复位 SPI2 外设到缺省状态 */ SPI_I2S_DeInit(I2S2ext); I2Sext_InitStructure.I2S_Mode = I2S_Mode_SlaveTx; /* 配置I2S工作模式 注意这里是SlaveTx 而不是Rx,容易误导*/ I2Sext_InitStructure.I2S_Standard = _usStandard; /* 接口标准 */ I2Sext_InitStructure.I2S_DataFormat = _usWordLen; /* 数据格式,16bit */ I2Sext_InitStructure.I2S_MCLKOutput = I2S_MCLKOutput_Disable; /* 主时钟模式 */ I2Sext_InitStructure.I2S_AudioFreq = _usAudioFreq; /* 音频采样频率 */ I2Sext_InitStructure.I2S_CPOL = I2S_CPOL_Low; I2S_Init(I2S2ext, &I2Sext_InitStructure); I2S_FullDuplexConfig(I2S2ext, &I2Sext_InitStructure); //可以进入函数中看到,当I2S_Mode == I2S_Mode_SlaveTx时,选择的是�tmp = I2S_Mode_SlaveRx; /* 使能 SPI2/I2S2 外设 */ I2S_Cmd(I2S2ext, ENABLE); SPI_I2S_DMACmd(I2S2ext,SPI_I2S_DMAReq_Rx,ENABLE);//SPI2 RX DMA请求使能. }
这里注意下I2S模式选的是I2S_Mode_SlaceTx,你可能会觉得这个地方配置错了。这地方我也是查询了好久才找到。坑爹玩意
I2Sext_InitStructure.I2S_Mode = I2S_Mode_SlaveTx; /* 配置I2S工作模式 注意这里是SlaveTx 而不是Rx,容易误导*/
其实不是,进到void I2S_FullDuplexConfig(SPI_TypeDef* I2Sxext, I2S_InitTypeDef* I2S_InitStruct) 这个函数里头,发现这代码是这样写的,最终是temp=I2S_Mode_SlaveRx;
/* Get the mode to be configured for the extended I2S */ if ((I2S_InitStruct->I2S_Mode == I2S_Mode_MasterTx) || (I2S_InitStruct->I2S_Mode == I2S_Mode_SlaveTx)) { tmp = I2S_Mode_SlaveRx; } else { if ((I2S_InitStruct->I2S_Mode == I2S_Mode_MasterRx) || (I2S_InitStruct->I2S_Mode == I2S_Mode_SlaveRx)) { tmp = I2S_Mode_SlaveTx; } }
(3)、配置DMA双缓冲发送和发送完产生的中断函数:
#define WM8960_I2Sx_DMA DMA1 #define WM8960_I2Sx_DMA_CLK RCC_AHB1Periph_DMA1 #define WM8960_I2Sx_TX_DMA_CHANNEL DMA_Channel_0 #define WM8960_I2Sx_TX_DMA_STREAM DMA1_Stream4 #define WM8960_I2Sx_TX_DMA_IT_TCIF DMA_IT_TCIF4 #define WM8960_I2Sx_TX_DMA_STREAM_IRQn DMA1_Stream4_IRQn #define WM8960_I2Sx_TX_DMA_STREAM_IRQFUN DMA1_Stream4_IRQHandler void WM8960_I2Sx_TX_DMA_Init(const uint16_t *buffer0,const uint16_t *buffer1,const uint32_t num) { NVIC_InitTypeDef NVIC_InitStructure; DMA_InitTypeDef DMA_InitStructure; RCC_AHB1PeriphClockCmd(WM8960_I2Sx_DMA_CLK,ENABLE);//DMA1时钟使能 DMA_DeInit(WM8960_I2Sx_TX_DMA_STREAM); while (DMA_GetCmdStatus(WM8960_I2Sx_TX_DMA_STREAM) != DISABLE){}//等待DMA1_Stream4可配置 DMA_ClearITPendingBit(WM8960_I2Sx_TX_DMA_STREAM,DMA_IT_FEIF4|DMA_IT_DMEIF4|DMA_IT_TEIF4|DMA_IT_HTIF4|DMA_IT_TCIF4);//清空DMA1_Stream4上所有中断标志 /* 配置 DMA Stream */ DMA_InitStructure.DMA_Channel = WM8960_I2Sx_TX_DMA_CHANNEL; //通道0 SPIx_TX通道 DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&WM8960_I2Sx_SPI->DR;//外设地址为:(u32)&SPI2->DR DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)buffer0;//DMA 存储器0地址 DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;//存储器到外设模式 DMA_InitStructure.DMA_BufferSize = num;//数据传输量 DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//外设非增量模式 DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;//存储器增量模式 DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;//外设数据长度:16位 DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;//存储器数据长度:16位 DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;// 使用循环模式 DMA_InitStructure.DMA_Priority = DMA_Priority_High;//高优先级 DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; //不使用FIFO模式 DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull; DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;//外设突发单次传输 DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//存储器突发单次传输 DMA_Init(WM8960_I2Sx_TX_DMA_STREAM, &DMA_InitStructure);//初始化DMA Stream DMA_DoubleBufferModeConfig(WM8960_I2Sx_TX_DMA_STREAM,(uint32_t)buffer0,DMA_Memory_0);//双缓冲模式配置 DMA_DoubleBufferModeConfig(WM8960_I2Sx_TX_DMA_STREAM,(uint32_t)buffer1,DMA_Memory_1);//双缓冲模式配置 DMA_DoubleBufferModeCmd(WM8960_I2Sx_TX_DMA_STREAM,ENABLE);//双缓冲模式开启 DMA_ITConfig(WM8960_I2Sx_TX_DMA_STREAM,DMA_IT_TC,ENABLE);//开启传输完成中断 DMA_Cmd(WM8960_I2Sx_TX_DMA_STREAM,DISABLE); NVIC_InitStructure.NVIC_IRQChannel = WM8960_I2Sx_TX_DMA_STREAM_IRQn; NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;//抢占优先级1 NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;//子优先级2 NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;//使能外部中断通道 NVIC_Init(&NVIC_InitStructure);//配置 } void WM8960_I2Sx_TX_DMA_STREAM_IRQFUN(void) { if(DMA_GetITStatus(WM8960_I2Sx_TX_DMA_STREAM,WM8960_I2Sx_TX_DMA_IT_TCIF)==SET)//DMA传输完成标志 { DMA_ClearITPendingBit(WM8960_I2Sx_TX_DMA_STREAM,WM8960_I2Sx_TX_DMA_IT_TCIF);//清DMA传输完成标准 if(WM8960_I2Sx_TX_DMA_STREAM->CR&(1<<19)) //当前使用Memory1数据 { bufflag=0; //可以将数据读取到缓冲区0 } else //当前使用Memory0数据 { bufflag=1; //可以将数据读取到缓冲区1 } Isread_tx ++; } }
(4)、配置DMA双缓冲接收和接收中断函数:
void WM8960_I2Sxext_RX_DMA_Init(const uint16_t *buffer0,const uint16_t *buffer1,const uint32_t num) { NVIC_InitTypeDef NVIC_InitStructure1; DMA_InitTypeDef DMA_InitStructure1; RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1,ENABLE);//DMA1时钟使能 DMA_DeInit(DMA1_Stream3); while (DMA_GetCmdStatus(DMA1_Stream3) != DISABLE){}//等待DMA1_Stream3可配置 DMA_ClearITPendingBit(DMA1_Stream3,DMA_IT_FEIF3|DMA_IT_DMEIF3|DMA_IT_TEIF3|DMA_IT_HTIF3|DMA_IT_TCIF3);//清空DMA1_Stream3上所有中断标志 /* 配置 DMA Stream */ DMA_InitStructure1.DMA_Channel = DMA_Channel_3; //通道0 SPIx_TX通道 DMA_InitStructure1.DMA_PeripheralBaseAddr = (uint32_t)&WM8960_I2Sx_ext->DR;//外设地址为:(u32)&SPI2->DR DMA_InitStructure1.DMA_Memory0BaseAddr = (uint32_t)buffer0;//DMA 存储器0地址 DMA_InitStructure1.DMA_DIR = DMA_DIR_PeripheralToMemory;//外设到存储器模式 DMA_InitStructure1.DMA_BufferSize = num;//数据传输量 DMA_InitStructure1.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//外设非增量模式 DMA_InitStructure1.DMA_MemoryInc = DMA_MemoryInc_Enable;//存储器增量模式 DMA_InitStructure1.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;//外设数据长度:16位 DMA_InitStructure1.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;//存储器数据长度:16位 DMA_InitStructure1.DMA_Mode = DMA_Mode_Circular;// 使用循环模式 DMA_InitStructure1.DMA_Priority = DMA_Priority_VeryHigh; DMA_InitStructure1.DMA_FIFOMode = DMA_FIFOMode_Disable; //不使用FIFO模式 DMA_InitStructure1.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull; DMA_InitStructure1.DMA_MemoryBurst = DMA_MemoryBurst_Single;//外设突发单次传输 DMA_InitStructure1.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//存储器突发单次传输 DMA_Init(DMA1_Stream3, &DMA_InitStructure1);//初始化DMA Stream DMA_DoubleBufferModeConfig(DMA1_Stream3,(uint32_t)buffer0,DMA_Memory_0);//双缓冲模式配置 DMA_DoubleBufferModeConfig(DMA1_Stream3,(uint32_t)buffer1,DMA_Memory_1);//双缓冲模式配置 DMA_DoubleBufferModeCmd(DMA1_Stream3,ENABLE);//双缓冲模式开启 DMA_ITConfig(DMA1_Stream3,DMA_IT_TC,ENABLE);//开启传输完成中断 DMA_Cmd(DMA1_Stream3,DISABLE); NVIC_InitStructure1.NVIC_IRQChannel = DMA1_Stream3_IRQn; NVIC_InitStructure1.NVIC_IRQChannelPreemptionPriority = 0;//抢占优先级0 NVIC_InitStructure1.NVIC_IRQChannelSubPriority = 0;//子优先级2 NVIC_InitStructure1.NVIC_IRQChannelCmd = ENABLE;//使能外部中断通道 NVIC_Init(&NVIC_InitStructure1);//配置 } void DMA1_Stream3_IRQHandler(void) { if(DMA_GetITStatus(DMA1_Stream3,DMA_IT_TCIF3)==SET) { DMA_ClearITPendingBit(DMA1_Stream3,DMA_IT_TCIF3); if(DMA1_Stream3->CR&(1<<19)) //当前使用Memory1数据 { bufflag=1; } else //当前使用Memory0数据 { bufflag=0; } Isread_rx++; // DMA传输完成标志 } }
(5)、主函数中调用测试语音录音和播放:
void WM8960_I2S_Play_Start(void) { DMA_Cmd(WM8960_I2Sx_TX_DMA_STREAM,ENABLE);//开启DMA TX传输,开始播放 } void WM8960_I2S_Play_Stop(void) { DMA_Cmd(WM8960_I2Sx_TX_DMA_STREAM,DISABLE);//关闭DMA TX传输,结束播放 } void WM8960_I2Sxext_Recorde_Start(void) { DMA_Cmd(WM8960_I2Sxext_RX_DMA_STREAM,ENABLE);//开启DMA RX传输,开始录音 } void WM8960_I2Sxext_Recorde_Stop(void) { DMA_Cmd(WM8960_I2Sxext_RX_DMA_STREAM,DISABLE);//关闭DMA RX传输,结束录音 }
extern u8 Isread_tx; extern u8 Isread_rx;
//注意两个数组别定义太大,定义太大STM空间不够,编译器会报错,这里一个数组存放了48630,两个数组48630*2 extern uint16_t adudio_buffer0[]; //可以事先定义好一个数组buffer0,先存放一点数据进去,不录音之前,也能播放一段声音出来 extern uint16_t adudio_buffer1[]; //可以事先定义好一个数组buffer1,先存放一点数据进去,不录音之前,也能播放一段声音出来 extern uint16_t ADUDIO_BUFFER_SIZE; //uint16_t ADUDIO_BUFFER_SIZE = sizeof(adudio_buffer0)/sizeof(uint16_t); #define DMA_Point_to_Memory0 0 #define DMA_Point_to_Memory1 1 void Audio_Set(void) { WM8960_I2S_GPIO_Config(); //I2S IO配置 if(WM8960_Set_Play_Recorde_Reg())//对WM8960进行初始化 { printf("WM8960 Init Fail!!! "); } else printf("WM8960 Init Success!!! "); WM8960_I2Sx_Mode_Config(I2S_Standard_Phillips,I2S_DataFormat_16b,I2S_AudioFreq_16k);//音频采样速率,这里配置16K,收发要保持一致 WM8960_I2Sx_TX_DMA_Init(adudio_buffer1,adudio_buffer0,ADUDIO_BUFFER_SIZE);//注意数量大小就是一个缓冲区的大小,而不是两个缓冲区大小之和,buffer1传给memory0,buffer0传给memory1 WM8960_I2Sxext_Mode_Config(I2S_Standard_Phillips,I2S_DataFormat_16b,I2S_AudioFreq_16k);//音频采样速率,这里配置16K,收发保持一致,否则播放出的音速就变了
//假如现在有一段录音“1234”,再同一时间内,44K采集到的数据比16K采集的数据多,加上STM数组空间有限,如果用44K采集的话,可能采集到“12”就填满了两个数组,录音播放的时候就只能听到前半截.
//如果用16K去采集数据,“1234”都能存到两个数组中,录音播放就会比较完整。这里的44K好比就是无损音乐,数据大;16K就相当于MP3格式的音乐,数据少。常规听起来感觉到不差异。
//这里就是要配置ADC/DAC采样速率16K的原因。
WM8960_I2Sxext_RX_DMA_Init(adudio_buffer1,adudio_buffer0,ADUDIO_BUFFER_SIZE); //配置I2S DMA双缓冲接收,buffer1传给memory0,buffer0传给memory1 } void Audio_Play_Recorde(void) { Audio_Set(); while(1) { //播放音乐 if(KEYL==0)//按下左按键,进行播放 { Delay_ms(1000); WM8960_I2S_Play_Start();//开启播放 } if(Isread_tx == 2) { WM8960_I2S_Play_Stop();//两个数组的数据播放完后,停止播放 Isread_tx = 0;//标志清0 printf("Play Complete!!! "); printf("Please Recorde!!! "); } if(KEYR==0)//按下右键将两个数组清0 { Delay_ms(1000); memset(adudio_buffer1,0,sizeof(uint16_t)*ADUDIO_BUFFER_SIZE); memset(adudio_buffer0,0,sizeof(uint16_t)*ADUDIO_BUFFER_SIZE); printf("Clear Buffer Complete!!! "); } //录音 if(KEYM==0)//按下左键,开启录音 { Delay_ms(1000); WM8960_I2Sxext_Recorde_Start();//开始录音 } if(Isread_rx == 2) { WM8960_I2Sxext_Recorde_Stop();//录满两个数组后,停止录音 Isread_rx = 0;//标志清0 printf("Recorde Complete!!! "); printf("Please Play!!! "); } // // if(bufflag==DMA_Point_to_Memory0) //说明Memory1中的数据可以拷贝 // { // rx_flag = 2; // memcpy(tx_buffer0,rx_buffer0,sizeof(u8)*BUFFER_SIZE); // } // if(bufflag==DMA_Point_to_Memory1)//说明Memory0中的数据可以拷贝 // { // rx_flag = 2; // memcpy(tx_buffer1,rx_buffer1,sizeof(u8)*BUFFER_SIZE); // } } }
总结:
(1)、为什么STM32配置主机,WM8960作为从机,能播放,但是接收不了数据,所以始终进不了中断函数,就无法录音?
答:播放时,是STM32将数据发给WM8960,是主动发送数据,会有时钟输出,而录音时,是STM32接收数据,
一直在那等待数据,示波器量MCLK 和Bitcllk没有时钟,虽然程序里配置使能MCLK时钟输出,但就是没有。
后来想到SPI接收数据的场景,在接收数据时,得让STM32发送任意字节,目的就是让时钟输出。接收不了数据的问题估计就是出在这里了。
static uint16_t SPIx_Receive_byte(void) { while(SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_TXE)==RESET); //检查缓冲区是否为空 SPI_I2S_SendData(SPI2,Dummy_Byte);//发送任意字节,就是为了时钟输出 while(SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_RXNE)==RESET); return SPI_I2S_ReceiveData(SPI2); }
我想STM32肯定可以做主机接收数据,只是现在没调试好,如果在接收时,是通过STM32发送数据产生时钟,那么WM8960会不会有杂音播放呢?
再一个采用的是DMA方式读取,看不到类似SPI那种接收读取的函数。又该如何配置呢? 这个问题可以好好研究。
(2)、在一个就是I2S 接收时的配置,虽然网上例子中,I2Sext_InitStructure.I2S_Mode = I2S_Mode_SlaveTx; 没有重点说明,
一开始按照网上的资料配置,不能录音,仔细检查代码,发现这个有疑问,明明是接收,怎么是配置为发送呢,让我窃喜,肯定是这个地方出错了,
于是改成了I2Sext_InitStructure.I2S_Mode = I2S_Mode_SlaveRx; 结果很失望,还是不能录音,于是单步调试进入I2S_FullDuplexConfig(I2S2ext, &I2Sext_InitStructure);
函数中,发现里面有这一段代码,原来如此,之前人家配置的I2S_Mode_SlaveTX是正确的。单步调试进入官方的库函数,仔细查看函数里面做了哪些,这种方法是非常有效。
if ((I2S_InitStruct->I2S_Mode == I2S_Mode_MasterTx) || (I2S_InitStruct->I2S_Mode == I2S_Mode_SlaveTx)) { tmp = I2S_Mode_SlaveRx; } else { if ((I2S_InitStruct->I2S_Mode == I2S_Mode_MasterRx) || (I2S_InitStruct->I2S_Mode == I2S_Mode_SlaveRx)) { tmp = I2S_Mode_SlaveTx; } }
还有个细节,在配置I2S接收工作模式时,I2S_Init要不要写?"因为看到了I2S_FullDuplexConfig(I2S2ext, &I2Sext_InitStructure);
也是将I2Sext_InitStructure变量传进去进行初始化,I2S_Init()是不是多余了,这个还真不是多余,得一定要配置,I2S_Init()是对I2S协议、
数据格式、主时钟、音频采样、工作模式和空闲时的时钟电平状态进行初始化,而I2S_FullDuplexConfig函数仅仅是将I2S2ext扩展口设置为全双工模式。
I2S_Init(I2S2ext, &I2Sext_InitStructure); I2S_FullDuplexConfig(I2S2ext, &I2Sext_InitStructure); //可以进入函数中看到,当I2S_Mode == I2S_Mode_SlaveTx时,选择的是�tmp = I2S_Mode_SlaveRx;
(3)、其实到现在我还有个疑问?I2S2ext扩展口设置全双工模式时使用,全双工的无非就是发送时,一根数据线在发送,另一根数据线在接收,看下引脚对应
* I2S总线传输音频数据口线
* WM8960_LRC -> PB12/I2S2_WS //映射到NSS引脚,即帧时钟,用于切换左右声道的数据,WS频率等于音频信号采样率(fs),
//STM32发送时是要产生一个时钟给WM8960,WM8960根据该时钟区分左右声道,接收时呢? 目前程序里面好像是不用关心,是真的吗?
* WM8960_BCLK -> PB13/I2S2_CK //串行时钟(映射到SPI_SCK引脚),即位时钟,是主模式下的串行时钟输出以及从模式下的串行时钟输入。
* WM8960_ADCDAT -> PB14/I2S2ext_SD//扩展串行数据线(MISO),用于全双工传输的数据接收
* WM8960_DACDAT -> PB15/I2S2_SD //串行数据线(映射MOSI),用于发送或接收两个时分复用的数据通道上的数据(仅半双工模式),如果是全双工模式,该信号仅用于发送数据
* WM8960_MCLK -> PC6/I2S2_MCK //附加时钟,给外设音频模块提供工作主时钟
目前程序里好像只用到了半双工,收发都不是同时。