STM32---DMA(USART)的演示

//设置NVIC优先级分组为Group2：0-3抢占式优先级，0-3的响应式优先级
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
//串口接收中断打开
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}

/*******************************************************************************
* Name : USART1_Configuration
* Deion : NUSART1设置
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void USART1_Configuration(void)
{
USART_InitTypeDef USART_InitStructure;

USART_InitStructure.USART_BaudRate = 9600;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_Parity = USART_Parity_No;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStructure.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
USART_Init(USART1, &USART_InitStructure);

USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);

USART_Cmd(USART1, ENABLE);
}

void DMA_Configuration(void)
{
DMA_InitTypeDef DMA_InitStructure;
//DMA设置：
//设置DMA源：内存地址&串口数据寄存器地址
//方向：内存-->外设
//每次传输位：8bit
//传输大小DMA_BufferSize=SENDBUFF_SIZE
//地址自增模式：外设地址不增，内存地址自增1
//DMA模式：一次传输，非循环
//优先级：中
DMA_DeInit(DMA1_Channel4);
DMA_InitStructure.DMA_PeripheralBaseAddr = USART1_DR_Base;
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)SendBuff;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
DMA_InitStructure.DMA_BufferSize = SENDBUFF_SIZE;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel4, &DMA_InitStructure);
}