STM32F4xx 外部按键控制 DMA 传输数据到 USART1

#include "stm32f4xx.h"\n\n#define DATA_SIZE 1000\n\nuint8_t data[DATA_SIZE]; // 数据缓冲区\n\nvoid GPIO_Configuration(void);\nvoid DMA_Configuration(void);\nvoid USART_Configuration(void);\n\nint main(void)\n{\n\tGPIO_Configuration(); // 配置外部按键\n\tDMA_Configuration(); // 配置 DMA\n\tUSART_Configuration(); // 配置 USART1\n\t\n\twhile (1)\n\t{\n\t if (GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_0) == Bit_RESET) // 检测外部按键 KEY_UP 是否被按下\n\t {\n\t DMA_Cmd(DMA2_Stream7, ENABLE); // 使能 DMA 传输\n\t while (DMA_GetFlagStatus(DMA2_Stream7, DMA_FLAG_TCIF7) == RESET); // 等待 DMA 传输完成\n\t DMA_ClearFlag(DMA2_Stream7, DMA_FLAG_TCIF7); // 清除 DMA 传输完成标志\n\t \n\t GPIO_ToggleBits(GPIOD, GPIO_Pin_12); // 在每次传输完数据后，切换 LED 灯状态\n\t }\n\t}\n}\n\nvoid GPIO_Configuration(void)\n{\n GPIO_InitTypeDef GPIO_InitStructure;\n\t\n RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);\n\t\n GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;\n GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;\n GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;\n GPIO_Init(GPIOA, &GPIO_InitStructure);\n\t\n RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);\n\t\n GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;\n GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;\n GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;\n GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;\n GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;\n GPIO_Init(GPIOD, &GPIO_InitStructure);\n}\n\nvoid DMA_Configuration(void)\n{\n DMA_InitTypeDef DMA_InitStructure;\n\t\n RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);\n\t\n DMA_InitStructure.DMA_Channel = DMA_Channel_4;\n DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&USART1->DR;\n DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)data;\n DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;\n DMA_InitStructure.DMA_BufferSize = DATA_SIZE;\n DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;\n DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;\n DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;\n DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;\n DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;\n DMA_InitStructure.DMA_Priority = DMA_Priority_High;\n DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;\n DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;\n DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;\n DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;\n DMA_Init(DMA2_Stream7, &DMA_InitStructure);\n\t\n DMA_Cmd(DMA2_Stream7, DISABLE);\n\t\n NVIC_InitTypeDef NVIC_InitStructure;\n\t\n NVIC_InitStructure.NVIC_IRQChannel = DMA2_Stream7_IRQn;\n NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;\n NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;\n NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;\n NVIC_Init(&NVIC_InitStructure);\n\t\n DMA_ITConfig(DMA2_Stream7, DMA_IT_TC, ENABLE);\n}\n\nvoid USART_Configuration(void)\n{\n GPIO_InitTypeDef GPIO_InitStructure;\n USART_InitTypeDef USART_InitStructure;\n\t\n RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);\n RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);\n\t\n GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;\n GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;\n GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;\n GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;\n GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;\n GPIO_Init(GPIOB, &GPIO_InitStructure);\n\t\n GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_USART1);\n GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_USART1);\n\t\n USART_InitStructure.USART_BaudRate = 115200;\n USART_InitStructure.USART_WordLength = USART_WordLength_8b;\n USART_InitStructure.USART_StopBits = USART_StopBits_1;\n USART_InitStructure.USART_Parity = USART_Parity_No;\n USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;\n USART_InitStructure.USART_Mode = USART_Mode_Tx;\n USART_Init(USART1, &USART_InitStructure);\n\t\n USART_Cmd(USART1, ENABLE);\n\t\n USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE);\n}\n\nvoid DMA2_Stream7_IRQHandler(void)\n{\n if (DMA_GetITStatus(DMA2_Stream7, DMA_IT_TCIF7) != RESET)\n {\n DMA_ClearITPendingBit(DMA2_Stream7, DMA_IT_TCIF7);\n DMA_Cmd(DMA2_Stream7, DISABLE);\n }\n