1.拼接字符串
static char SEND_S[13] = {'A','T','+','C','I','P','S','E','N','D','=','1',','}; static char SEND_X[23] = {',','"','1','9','2','.','1','6','8','.','1','0','.','1','"',',','8','8','8','9',' ',' '}; static char COMMAND[99]; memset( COMMAND, 0, sizeof( COMMAND) ); strcat( COMMAND, SEND_S); strcat( COMMAND, SEND_X);
2.对比字符串
if( strstr(_udp_rece,"WIFI DISCONNECT") != 0 ) //wifi断开 { }
3.字符串转整型
int char_int( const char *cha ) //字符串转整型 { u8 data[8]={0,0,0,0,0,0,0,0}; int temp = 0,ret = 0; u8 num = 0,err = 0,i = 0,j=0; //位数 正负 while( *cha ) { if( ( *cha >= '0') && ( *cha <= '9' ) ) { data[num] = (*cha - '0'); num++; } if( *cha == '-' ) //负号 { err = 1; } cha++; } for( j = 0; j < num; j++ ) { temp = data[j]; for( i = num - j - 1; i>0 ; i-- ) { temp *= 10; } ret += temp; } if( err == 1 ) { ret = -ret; } return ret; }
4.整型转字符串
void itoa (int n,char *s) //整型转字符串 { char temp[10]; int i = 1,j = 0,sign = 0; memset( temp, 0 ,10 ); if( n < 0 )//记录符号 { n=-n;//使n成为正数 sign = -1; } do { temp[i++]=n%10+'0';//取下一个数字 } while ((n/=10)>0);//删除该数字 if(sign<0) { temp[i++]='-'; } temp[0]=' '; for(j=i-1;j>=0;j--)//生成的数字是逆序的，所以要逆序输出 { *s = temp[j]; s++; } }
5.取出指定的数据：
字符串数据为：mid:xxx,x:xxx,y:xxx,z:xxx,yaw:xxx,h:xxx中间数据位数不固定 static void req_tello(const char *req) { u8 step = 0,i=0; u16 j = 0; char *mid = "mid:"; char *yaw = ";yaw:"; char *h = ";h:"; char *temp; j = _rece_num; while(j--) { switch ( step ) { case 0: //取出mid数据 temp = strstr( req,mid); while( *temp != ':' ) { temp++; } while(1) { temp++; if( *temp == ';' ) //跳出 { i = 0; step = 1; break; } else { requ_tello[step][i] = *temp; i++; } } break; case 1: //取出x轴坐标数据 while( *temp != ':' ) { temp++; } while(1) { temp++; if( *temp == ';' ) //跳出 { i = 0; step = 2; break; } else { requ_tello[step][i] = *temp; i++; } } break; case 2: //取出y轴坐标数据 while( *temp != ':' ) { temp++; } while(1) { temp++; if( *temp == ';' ) //跳出 { i = 0; step = 3; break; } else { requ_tello[step][i] = *temp; i++; } } break; case 3: //取出z轴坐标数据 while( *temp != ':' ) { temp++; } while(1) { temp++; if( *temp == ';' ) //跳出 { i = 0; step = 4; break; } else { requ_tello[step][i] = *temp; i++; } } break; case 4: //取出航偏角数据 temp = strstr( temp,yaw); while( *temp != ':' ) { temp++; } while(1) { temp++; if( *temp == ';' ) //跳出 { i = 0; step = 5; break; } else { requ_tello[step][i] = *temp; i++; } } break; case 5: //取出高度数据 temp = strstr( temp,h); while( *temp != ':' ) { temp++; } while(1) { temp++; if( *temp == ';' ) //跳出 { i = 0; step = 6; break; } else { requ_tello[step][i] = *temp; i++; } } break; case 6: //将取出的字符串数据转换为整型 for( i=0; i<6; i++ ) { tello_data[i] = char_int( &requ_tello[i][0] ); } _send_data[0] = 0x6A; _send_data[1] = 0x6A; _send_data[2] = BYTE1( tello_data[0] ); _send_data[3] = BYTE0( tello_data[0] ); _send_data[4] = BYTE1( tello_data[1] ); _send_data[5] = BYTE0( tello_data[1] ); _send_data[6] = BYTE1( tello_data[2] ); _send_data[7] = BYTE0( tello_data[2] ); _send_data[8] = BYTE1( tello_data[3] ); _send_data[9] = BYTE0( tello_data[3] ); _send_data[10] = BYTE1( tello_data[4] ); _send_data[11] = BYTE0( tello_data[4] ); _send_data[12] = BYTE1( tello_data[5] ); _send_data[13] = BYTE0( tello_data[5] ); memset(requ_tello,0,sizeof(requ_tello)); _sendflag = 1; step = 7; break; } if( step == 7 ) { break; } } }
6.利用空闲中断接收不固定长度的数据
stm32f103系列： void USART1_Configuration(void) //串口1配置---M { DMA_InitTypeDef DMA_InitStructure; USART_InitTypeDef USART_InitStructure; GPIO_InitTypeDef GPIO_InitStructure; NVIC_InitTypeDef NVIC_InitStructure; // DMA_InitTypeDef DMA_InitStructure; RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE); DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&( USART1->DR); DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)_udp_rece; DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; DMA_InitStructure.DMA_BufferSize = RESUM; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; //HalfWord DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; DMA_InitStructure.DMA_Mode = DMA_Mode_Circular ; // DMA_Mode_Normal DMA_InitStructure.DMA_Priority = DMA_Priority_High; //DMA_Priority_Low DMA_Priority_Medium DMA_Priority_High DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; DMA_Init(DMA1_Channel5, &DMA_InitStructure); //NVIC 设置，使能中断 NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1); //选择中断分组1 NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn; //选择串口3中断 NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1; //抢占式中断优先级设置为1 NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //响应式中断优先级设置为1 NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //使能中断 NVIC_Init(&NVIC_InitStructure); USART_ITConfig(USART1, USART_IT_IDLE, ENABLE);//开启中断 //USART1 //TX GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_Init(GPIOA, &GPIO_InitStructure); //RX GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_Init(GPIOA, &GPIO_InitStructure); USART_OverSampling8Cmd(USART1, ENABLE); USART_InitStructure.USART_BaudRate = 115200; 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_Init(USART1, &USART_InitStructure); USART_DMACmd(USART1,USART_DMAReq_Rx,ENABLE); DMA_Cmd(DMA1_Channel5, ENABLE); USART_Cmd(USART1, ENABLE); USART1->SR; USART1->DR; }
void USART1_IRQHandler(void) { flagus1 = USART1->SR; if( USART_GetFlagStatus( USART1, USART_FLAG_IDLE ) == SET ) //发生空闲中断 { DMA_Cmd(DMA1_Channel5, DISABLE); //关闭DMA输出 _rece_num = RESUM - DMA1_Channel5 ->CNDTR; //获取读到的字节数 for( u8 i = 0; i < _rece_num; i++ ) { _rece_data[i] = _udp_rece[i]; } //处理数据 DMA1_Channel5->CNDTR = RESUM; //重新填充 DMA_Cmd(DMA1_Channel5, ENABLE); //开启DMA传输 USART_ClearITPendingBit( USART1, USART_IT_IDLE ); //清除中断 ｝ USART1->SR; USART1->DR; ｝