最近用stm32f407做一个sd卡mp3解码后，音频传输的项目，声卡芯片用的VM8978，采取的是SPI3的i2s，用的DMA是DMA1的stream5通道0.用的是主发送模式
在dma中断中我用一个led反转看是否进入中断，结果是，中断进入，但i2s 引脚为何没有输出，按道理说应该是有波形输出的啊 BCLk脚怎么一直是低电平了？
求各位大侠赐教！！
程序如下：
DMA_InitTypeDef DMA_InitStructure;
u32 AudioTotalSize = 0xffff;
u32 AudioRemSize = 0;
u16 *CurrentPos;
extern void AUDIO_TransferComplete(u32 pBuffer, uint32_t Size);
void AUDIO_Init(u32 AudioFreq)
{
Audio_I2S_Init(AudioFreq);
I2S_GPIO_Init();
Audio_DMA_Init();
}
void I2s_GPIO_DEinit(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
/* I2S3S_WS */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_15;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* I2S3_CK, I2S3_SD, I2S3ext_SD */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3 | GPIO_Pin_4 | GPIO_Pin_5;
GPIO_Init(GPIOB, &GPIO_InitStructure);
}
void I2S_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
I2s_GPIO_DEinit();
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, 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_UP;
/* Connect pins to I2S peripheral */
GPIO_PinAFConfig(GPIOA, GPIO_PinSource15, GPIO_AF_SPI3);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource3, GPIO_AF_SPI3);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource4, GPIO_AF_I2S3ext);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource5, GPIO_AF_SPI3);
/* I2S3S_WS */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_15;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* I2S3_CK, I2S3_SD, I2S3ext_SD */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3 | GPIO_Pin_4 | GPIO_Pin_5;
GPIO_Init(GPIOB, &GPIO_InitStructure);
}
void Audio_I2S_Init(uint32_t AudioFreq)
{
I2S_InitTypeDef I2S_InitStructure;
SPI_I2S_DeInit(SPI3);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI3, ENABLE);
SPI_I2S_DeInit(SPI3);
I2S_InitStructure.I2S_AudioFreq = AudioFreq;
I2S_InitStructure.I2S_Standard = I2S_Standard_Phillips;
I2S_InitStructure.I2S_DataFormat = I2S_DataFormat_16b;
I2S_InitStructure.I2S_CPOL = I2S_CPOL_Low;
I2S_InitStructure.I2S_Mode = I2S_Mode_MasterTx;
I2S_InitStructure.I2S_MCLKOutput = I2S_MCLKOutput_Disable;
I2S_Init(SPI3, &I2S_InitStructure);
}
//DMA传送配置
void Audio_DMA_Init(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);
DMA_Cmd(DMA1_Stream5, DISABLE);
DMA_DeInit(DMA1_Stream5);
DMA_InitStructure.DMA_Channel = DMA_Channel_0;
DMA_InitStructure.DMA_PeripheralBaseAddr = 0x4000380C;
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)0;//该项将在播放函数中进行配置
DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
DMA_InitStructure.DMA_BufferSize = (uint32_t)0xFFFE;//该项将在播放函数中进行配置
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA1_Stream5, &DMA_InitStructure);
DMA_ITConfig(DMA1_Stream5, DMA_IT_TC, ENABLE);//使能所选DMA的中断
//I2S DMA中断通道配置
NVIC_InitStructure.NVIC_IRQChannel = DMA1_Stream5_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;//抢占优先级(0 最高)
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;//子优先级(0 最高)
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
SPI_I2S_DMACmd(SPI3, SPI_I2S_DMAReq_Tx, ENABLE);//中断请求使能
}
//开始从特定大小（Size）的缓冲区（pBuffer）中播放音频流
uint32_t AUDIO_Play(u16* pBuffer, u32 Size)
{
AudioTotalSize=Size;
Audio_MAL_Play((u32)pBuffer,(u32)(DMA_MAX(Size/4)));//更新媒体层数据并播放
AudioRemSize=(Size/2)-DMA_MAX(AudioTotalSize);//更新剩余数据量
CurrentPos=pBuffer+DMA_MAX(AudioTotalSize);//更新当新数据指针
return 0;
}
//开始播放媒体中的音频流
void Audio_MAL_Play(u32 Addr, u32 Size)
{
DMA_InitStructure.DMA_Memory0BaseAddr=(uint32_t)Addr;//配置缓冲区地址和大小
DMA_InitStructure.DMA_BufferSize=(uint32_t)Size/2;
DMA_Init(DMA1_Stream5,&DMA_InitStructure);
DMA_Cmd(DMA1_Stream5,ENABLE);//I2S DMA使能
if ((SPI3->I2SCFGR & I2S_ENABLE_MASK)==0)I2S_Cmd(SPI3,ENABLE);//若I2S接口未使能，则使能
}
//I2S中断处理
void SPI3_IRQHandler(void)
{
if (SPI_I2S_GetFlagStatus(SPI3,SPI_I2S_FLAG_TXE)!=RESET)
{
SPI_I2S_SendData(SPI3, 0);//发送空字节到I2S
SPI_I2S_ClearFlag(SPI3,SPI_I2S_FLAG_TXE);
}
}
//DMA中断处理函数
void DMA1_Stream5_IRQHandler(void)
{
//传送完成中断
if (DMA_GetFlagStatus(DMA1_Stream5, DMA_FLAG_TCIF5)!=RESET)
{
if (AudioRemSize>0)//查看是否到达文件尾
{
printf("DMA1\r\n");
while (DMA_GetCmdStatus(DMA1_Stream5) != DISABLE) IWDG_ReloadCounter();//等待DMA disabled
DMA_ClearFlag(DMA1_Stream5, DMA_FLAG_TCIF5);//清传送完成中断标志
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t) CurrentPos;//重新配置缓冲区地址和大小
DMA_InitStructure.DMA_BufferSize = (uint32_t) (DMA_MAX(AudioRemSize));
DMA_Init(DMA1_Stream5, &DMA_InitStructure);
DMA_Cmd(DMA1_Stream5, ENABLE);
CurrentPos += DMA_MAX(AudioRemSize);//更新数据指针
AudioRemSize -= DMA_MAX(AudioRemSize);//更新剩余数据
DMA_Cmd(DMA1_Stream5, ENABLE);
}
else//已到达文件尾
{
DMA_Cmd(DMA1_Stream5, DISABLE);
DMA_ClearFlag(DMA1_Stream5, DMA_FLAG_TCIF5);
AUDIO_TransferComplete((uint32_t)CurrentPos, 0);
STM_EVAL_LEDToggle(2); //led反转 ，显示状态
// printf("DMA2\r\n");
}
// printf("DMA3\r\n");
}
}
[ 本帖最后由 xslyk 于 2013-7-1 09:12 编辑 ]
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