FM33lc026n使用空闲中断+DMA实现数据接收代码

以下是使用空闲中断+DMA实现数据接收的示例代码：

#include "fm33lc0xx_fl_dma.h"
#include "fm33lc0xx_fl_uart.h"
#include "fm33lc0xx_fl_rcc.h"
#include "fm33lc0xx_fl_exti.h"

#define UART_RX_BUF_SIZE 256

uint8_t rx_buf[UART_RX_BUF_SIZE];
volatile uint16_t rx_index = 0;
FL_DMA_InitTypeDef dma_init_struct;
FL_UART_InitTypeDef uart_init_struct;
FL_EXTI_InitTypeDef exti_init_struct;

void uart_rx_dma_init(void)
{
    /* 使能DMA和UART时钟 */
    FL_RCC_EnableGroup1BusClock(FL_RCC_GROUP1_BUSCLK_DMA);
    FL_RCC_EnableGroup1BusClock(FL_RCC_GROUP1_BUSCLK_UART);

    /* 配置UART */
    FL_UART_StructInit(&uart_init_struct);
    uart_init_struct.UART_BaudRate = 115200;
    uart_init_struct.UART_WordLength = FL_UART_DATAWIDTH_8B;
    uart_init_struct.UART_StopBits = FL_UART_STOPBITS_1;
    uart_init_struct.UART_Parity = FL_UART_PARITY_NONE;
    uart_init_struct.UART_HardwareFlowControl = FL_UART_FLOWCTRL_NONE;
    uart_init_struct.UART_Mode = FL_UART_MODE_RX;
    FL_UART_Init(UART, &uart_init_struct);

    /* 配置DMA */
    dma_init_struct.DMA_Channel = FL_DMA_CHANNEL_0;
    dma_init_struct.DMA_PeripheralBaseAddr = (uint32_t)&UART->RBR;
    dma_init_struct.DMA_MemoryBaseAddr = (uint32_t)rx_buf;
    dma_init_struct.DMA_DIR = FL_DMA_DIR_PERIPHERAL_TO_MEMORY;
    dma_init_struct.DMA_BufferSize = UART_RX_BUF_SIZE;
    dma_init_struct.DMA_PeripheralInc = FL_DMA_PERIPHERAL_INC_DISABLE;
    dma_init_struct.DMA_MemoryInc = FL_DMA_MEMORY_INC_ENABLE;
    dma_init_struct.DMA_PeripheralDataSize = FL_DMA_PDATAWIDTH_BYTE;
    dma_init_struct.DMA_MemoryDataSize = FL_DMA_MDATAWIDTH_BYTE;
    dma_init_struct.DMA_Mode = FL_DMA_MODE_CIRCULAR;
    dma_init_struct.DMA_Priority = FL_DMA_PRIORITY_HIGH;
    FL_DMA_Init(&dma_init_struct);

    /* 配置空闲中断 */
    exti_init_struct.EXTI_Line = FL_EXTI_LINE_UART_RI;
    exti_init_struct.EXTI_Trigger = FL_EXTI_TRIGGER_FALLING;
    exti_init_struct.EXTI_LineCmd = ENABLE;
    FL_EXTI_Init(&exti_init_struct);
    FL_EXTI_EnableIT_FL_EXTI_LINE_UART_RI();
    FL_IRQ_EnableIRQ_UART_RI();

    /* 启动DMA */
    FL_DMA_EnableChannel(FL_DMA_CHANNEL_0);
}

void UART_RI_IRQHandler(void)
{
    /* 清除中断标志 */
    FL_UART_ClearFlag_RXNE(UART);
    FL_EXTI_ClearFlag_FL_EXTI_LINE_UART_RI();

    /* 禁用DMA */
    FL_DMA_DisableChannel(FL_DMA_CHANNEL_0);

    /* 处理接收到的数据 */
    rx_index = UART_RX_BUF_SIZE - FL_DMA_GetCurrDataCounter(FL_DMA_CHANNEL_0);
    if (rx_index > 0) {
        // do something with rx_buf
    }

    /* 重新启动DMA */
    FL_DMA_EnableChannel(FL_DMA_CHANNEL_0);
}

在上面的代码中，首先需要初始化UART和DMA，并启动DMA传输。当接收到数据时，空闲中断会触发，此时需要禁用DMA，处理接收到的数据，并重新启动DMA传输。注意，空闲中断和DMA都要在初始化时启用并配置相应的参数。