STM32实现完整SBUS协议解析与编码

#include "sbus.h" #include "stdio.h" typedef struct SBUS { uint8_t head; uint8_t ch[22]; //16个通道编码 struct { bool ch17 :1; //通道17 bool ch18 :1; //通道18 bool framlost :1; bool failsafe :1; uint8_t :4; }flage; uint8_t endbyte; //尾字节 }SBUS; typedef SBUS CHIN; CHIN code = {.head = 0XFF, .endbyte = 0X66}; //接受侦 SBUS ocode = {.head = 0X0F, .endbyte = 0X40}; //发送帧 void SBUS_init(void)//初始化串口 DMA 定时器 { DMA_InitTypeDef DMA_InitStructure; GPIO_InitTypeDef GPIO_InitStructure; USART_InitTypeDef USART_InitStructure; NVIC_InitTypeDef NVIC_InitStructure; RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC,ENABLE); RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART6,ENABLE); RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2,ENABLE); GPIO_PinAFConfig(GPIOC,GPIO_PinSource7,GPIO_AF_USART6); GPIO_PinAFConfig(GPIOC,GPIO_PinSource6,GPIO_AF_USART6); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //推挽复用输出 GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //上拉 GPIO_Init(GPIOC,&GPIO_InitStructure); USART_InitStructure.USART_BaudRate = 100000;//100K USART_InitStructure.USART_WordLength = USART_WordLength_9b;//字长为9位数据格式 USART_InitStructure.USART_StopBits = USART_StopBits_2;//一个停止位 USART_InitStructure.USART_Parity = USART_Parity_Even;//偶校验位 USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//无硬件数据流控制 USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //收发模式 USART_Init(USART6, &USART_InitStructure); USART_Cmd(USART6, ENABLE); USART_ITConfig(USART6, USART_IT_IDLE, ENABLE); //开启总线空闲中断 NVIC_InitStructure.NVIC_IRQChannel = USART6_IRQn; NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;//抢占优先级3 NVIC_InitStructure.NVIC_IRQChannelSubPriority =3; //子优先级3 NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; NVIC_Init(&NVIC_InitStructure); //usart6_tx while (DMA_GetCmdStatus(DMA2_Stream6) != DISABLE){}//等待DMAs2可配置 DMA_InitStructure.DMA_Channel = DMA_Channel_5; //通道选择 DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)&USART6->DR;//DMA外设地址 DMA_InitStructure.DMA_Memory0BaseAddr = NULL;//DMA 存储器0地址 DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;//存储器到外设模式 DMA_InitStructure.DMA_BufferSize = 0;//数据传输量 DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//外设非增量模式 DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;//存储器增量模式 DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;//外设数据长度:8位 DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;//存储器数据长度:8位 DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;// 使用普通模式 DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;//中等优先级 DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full; DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;//存储器突发单次传输 DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//外设突发单次传输 DMA_Init(DMA2_Stream6, &DMA_InitStructure); DMA_Cmd(DMA2_Stream6, DISABLE); //usatr6_rx while (DMA_GetCmdStatus(DMA2_Stream1) != DISABLE){} DMA_InitStructure.DMA_Channel = DMA_Channel_5; //通道选择 DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)&USART6->DR;//DMA外设地址 DMA_InitStructure.DMA_Memory0BaseAddr = (u32)&code;//DMA 存储器0地址 DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;//外设到存储器模式 DMA_InitStructure.DMA_BufferSize = 25;//数据传输量 DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//外设非增量模式 DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;//存储器增量模式 DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;//外设数据长度:8位 DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;//存储器数据长度:8位 DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;// 使用普通模式 DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;//最高优先级 DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full; DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;//存储器突发单次传输 DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//外设突发单次传输 DMA_Init(DMA2_Stream1, &DMA_InitStructure); DMA_Cmd(DMA2_Stream1, DISABLE); USART_DMACmd(USART6,USART_DMAReq_Tx,ENABLE); USART_DMACmd(USART6,USART_DMAReq_Rx,ENABLE); DMA_ClearFlag(DMA2_Stream6,DMA_FLAG_TCIF6); TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure; RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM7,ENABLE); RCC_ClocksTypeDef RCCClockStruct; RCC_GetClocksFreq(&RCCClockStruct); TIM_TimeBaseInitStructure.TIM_ClockDivision=TIM_CKD_DIV1; TIM_TimeBaseInitStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数模式 TIM_TimeBaseInitStructure.TIM_Prescaler = (RCCClockStruct.PCLK1_Frequency / 10000) - 1; //定时器分频10Khz TIM_TimeBaseInitStructure.TIM_Period = (int)(SENDINTERVAL * 10) - 1; //7ms重载 TIM10 7m定时发送 TIM_TimeBaseInit(TIM7,&TIM_TimeBaseInitStructure); TIM_ITConfig(TIM7,TIM_IT_Update,ENABLE); //允许定时器更新中断 NVIC_InitStructure.NVIC_IRQChannel=TIM7_IRQn; NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=0x01; //抢占优先级1 NVIC_InitStructure.NVIC_IRQChannelSubPriority=0x03; //子优先级3 NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE; NVIC_Init(&NVIC_InitStructure); TIM_Cmd(TIM7,ENABLE); //使能定时器 } // //解调 CHS inchs; //code //返回 false 接收失败 true 成功 char loscnt = 0;//接收错误计数 static uint64_t rtimeover = 0;//接收定时器发送中断超计数 bool decode(void)//解码,只能由串口空闲中断调用 { #ifdef ENDBYTEIDENT static uint8_t endbyt = 0X04; static bool firstz = true; //表示接收到的是第一帧数据 loscnt = (loscnt >=120) ? 120: (loscnt + 1); if(firstz == false) //上一帧接收成功 { if(endbyt == code.endbyte && code.head == 0X0F) //尾字节正确，和头字节正确 endbyt = (code.endbyte == 0X34) ? (0X04): (code.endbyte + 0X10); else { firstz = true; inchs.flage.framlost = true;//使能信号丢失标志 return false; } } else //上一帧不成功或者头帧数据 { if(code.head == 0X0F) //头字节正确 { switch(code.endbyte) { case 0X04 : {endbyt = 0X14; break;} case 0X14 : {endbyt = 0X24; break;} case 0X24 : {endbyt = 0X34; break;} case 0X34 : {endbyt = 0X04; break;} default: { inchs.flage.failsafe |= (loscnt) > 10; //连续丢失次数大于5 则使能保护 inchs.flage.framlost = true;//使能信号丢失标志 return false; //尾字节错误 } } firstz = false; } else { inchs.flage.failsafe |= (loscnt) > 10; //连续丢失次数大于5 则使能保护 inchs.flage.framlost = true;//使能信号丢失标志 return false; } } #else if(code.head != 0X0F || code.endbyte == 0X66) //尾字节为66说明没有接收完成 { inchs.flage.failsafe |= (loscnt) > 10; //连续丢失次数大于5 则使能保护 inchs.flage.framlost = true;//使能信号丢失标志 return false; } #endif loscnt = 0; rtimeover = 0; float* _channels = inchs.ch; uint16_t buffer[22]; uint8_t* tmp =code.ch; taskENTER_CRITICAL(); for(int i = 0;i<22;i++) buffer[i] = tmp[i]; *_channels++ = (((buffer[0] |buffer[1]<<8) & 0x07FF)) / 511.5 - 1; *_channels++ = (((buffer[1]>>3 |buffer[2]<<5) & 0x07FF)) / 511.5 - 1; *_channels++ = (((buffer[2]>>6 |buffer[3]<<2 |buffer[4]<<10) & 0x07FF)) / 511.5 - 1; *_channels++ = (((buffer[4]>>1 |buffer[5]<<7) & 0x07FF)) / 511.5 - 1; *_channels++ = (((buffer[5]>>4 |buffer[6]<<4) & 0x07FF)) / 511.5 - 1; *