diff --git a/app/inc/hardware.h b/app/inc/hardware.h index 1a7e2e0..c677362 100644 --- a/app/inc/hardware.h +++ b/app/inc/hardware.h @@ -1,8 +1,9 @@ #ifndef __HARDWARE_H #define __HARDWARE_H - +/*接收数组大小*/ #define MODBUS_RX_BUF_SIZE 256 +/*modbus通信波特率*/ #define MODBUS_USART_BAUDRATE 19200 diff --git a/app/src/hardware.c b/app/src/hardware.c index 54d3abe..f6d61a2 100644 --- a/app/src/hardware.c +++ b/app/src/hardware.c @@ -1,7 +1,9 @@ #include "stm32f4xx.h" #include "hardware.h" +/*接收数组*/ uint8_t ModbusRxBuf[MODBUS_RX_BUF_SIZE]; +/*接收数据长度*/ uint16_t ModbusRxLen = 0; void ModbusGpioInit(void) @@ -9,32 +11,37 @@ void ModbusGpioInit(void) GPIO_InitTypeDef GPIO_InitStructure; RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE); - + + /* PA9->USART1_TX，PA10->USART1_RX */ GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; - GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; + GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; /*推挽输出*/ GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; GPIO_Init(GPIOA, &GPIO_InitStructure); - + + /*复用初始化*/ GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_USART1); GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_USART1); } +/*硬件有自动收发转换芯片，软件实现modbus只需要当成普通的全双工串口使用即可*/ void ModbusUsartInit(void) { USART_InitTypeDef USART_InitStructure; RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE); - - USART_InitStructure.USART_BaudRate = MODBUS_USART_BAUDRATE; - 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_Rx | USART_Mode_Tx; + + USART_InitStructure.USART_BaudRate = MODBUS_USART_BAUDRATE; /*配置波特率*/ + USART_InitStructure.USART_WordLength = USART_WordLength_8b; /*数据帧长度8字节*/ + USART_InitStructure.USART_StopBits = USART_StopBits_1; /*1位停止位*/ + USART_InitStructure.USART_Parity = USART_Parity_No; /*无奇偶校验位，使用crc校验*/ + USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None; /*不使用硬件流控*/ + USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; /*发送接收全双工*/ USART_Init(USART1, &USART_InitStructure); + /*使能串口空闲中断（IDLE）*/ + /*当RX线路在接收过至少一个字节后，持续一个完整字符时间没有再收到数据，USART会置位IDLE标志并产生中断*/ USART_ITConfig(USART1, USART_IT_IDLE, ENABLE); USART_Cmd(USART1, ENABLE); } @@ -45,34 +52,35 @@ void ModbusDmaInit(void) RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE); - /* DMA2_Stream2 用于 USART1_RX */ - DMA_DeInit(DMA2_Stream2); - DMA_InitStructure.DMA_Channel = DMA_Channel_4; - DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART1->DR); - DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)ModbusRxBuf; - DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory; - DMA_InitStructure.DMA_BufferSize = MODBUS_RX_BUF_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_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; + /* DMA2_Stream2_Channel_4 用于 USART1_RX */ + DMA_DeInit(DMA2_Stream2); /*恢复默认状态*/ + DMA_InitStructure.DMA_Channel = DMA_Channel_4; /*配置通道4*/ + DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART1->DR); /*设置DMA外设端地址为USART1数据寄存器地址*/ + DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)ModbusRxBuf; /*设置DMA存储器目标地址为接收缓冲区首地址*/ + DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory; /*传输方向为外设->内存*/ + DMA_InitStructure.DMA_BufferSize = MODBUS_RX_BUF_SIZE; /*传输最大字节数*/ + DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; /*禁止外设地址递增*/ + DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; /*使能内存地址自增*/ + DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; /*设置外设数据宽度为1字节（8位）*/ + DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; /*设置内存数据宽度为1字节（8位）*/ + DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; /*modbus帧长度不固定，无法使用循环模式，配置为普通模式，每次传输完软件重新使能*/ + 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; /*禁止FIFO后无用*/ + DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; /*内存侧单次传输，每次搬运一个数据单位*/ + DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; /*外设侧单次传输，每次搬运一个数据单位*/ DMA_Init(DMA2_Stream2, &DMA_InitStructure); - /* DMA2_Stream7 用于 USART1_TX */ - DMA_DeInit(DMA2_Stream7); - DMA_InitStructure.DMA_Channel = DMA_Channel_4; - DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART1->DR); - DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; + /* DMA2_Stream7_Channel_4 用于 USART1_TX */ + /*USART1_TX的其他配置在USART中断中配置*/ + DMA_DeInit(DMA2_Stream7); + DMA_InitStructure.DMA_Channel = DMA_Channel_4; + DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART1->DR); /*设置DMA外设端地址为USART1数据寄存器地址*/ + DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; /*传输方向为内存->外设*/ DMA_Init(DMA2_Stream7, &DMA_InitStructure); /* 使能USART的DMA请求 */ - USART_DMACmd(USART1, USART_DMAReq_Rx | USART_DMAReq_Tx, ENABLE); + USART_DMACmd(USART1, USART_DMAReq_Rx | USART_DMAReq_Tx, ENABLE); /*使能USART1的RX、TX的DMA请求*/ DMA_Cmd(DMA2_Stream2, ENABLE); } @@ -80,9 +88,9 @@ void ModbusNvicInit(void) { NVIC_InitTypeDef NVIC_InitStructure; - NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn; - NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 5; - NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; + NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn; + NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 5; /*抢占优先级5*/ + NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; /*响应优先级0*/ NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; NVIC_Init(&NVIC_InitStructure); } @@ -90,6 +98,9 @@ void ModbusNvicInit(void) void MdobusHardwareInit(void) { + /*NVIC分组配置*/ + NVIC_PriorityGroupConfig(NVIC_PriorityGroup_4); /*4位抢占优先级，0位子优先级*/ + ModbusGpioInit(); ModbusUsartInit(); ModbusDmaInit();