树莓派串口读取陀螺仪ky9250(mpu9250)数据

9轴姿态角度传感器，其中ky9250陀螺仪由于自带卡尔曼动态滤波算法方便用户使用。ky9250陀螺仪基本可以在各个平台上进行数据的读取（如stm32\arduino\C#\Matlab\树莓\Unity3d\python\ROS\英飞凌\Nvidia jetson linux 等）

1、树莓派和ky9250的接线方式

树莓派和ky92509250的模块（VCC对3V3,RX对TX，TX对RX，GND对GND）

2、安装树莓ch340驱动（下载包中有）

3、上传电脑的示例代码文件到树莓派中

#include<stdio.h>
#include<stdlib.h>
#include<fcntl.h>
#include<unistd.h>
#include<assert.h>
#include<termios.h>
#include<string.h>
#include<sys/time.h>
#include<time.h>
#include<sys/types.h>
#include<errno.h>static int ret;
static int fd;#define BAUD 115200 //115200int uart_open(int fd,const char *pathname)
{fd = open(pathname, O_RDWR|O_NOCTTY); if (-1 == fd){ perror("Can't Open Serial Port"); return(-1); } elseprintf("open %s success!\n",pathname);if(isatty(STDIN_FILENO)==0) printf("standard input is not a terminal device\n"); else printf("isatty success!\n"); return fd; 
}int uart_set(int fd,int nSpeed, int nBits, char nEvent, int nStop)
{struct termios newtio,oldtio; if  ( tcgetattr( fd,&oldtio)  !=  0) {  perror("SetupSerial 1");printf("tcgetattr( fd,&oldtio) -> %d\n",tcgetattr( fd,&oldtio)); return -1; } bzero( &newtio, sizeof( newtio ) ); newtio.c_cflag  |=  CLOCAL | CREAD;  newtio.c_cflag &= ~CSIZE;  switch( nBits ) { case 7: newtio.c_cflag |= CS7; break; case 8: newtio.c_cflag |= CS8; break; } switch( nEvent ) { case 'o':case 'O': newtio.c_cflag |= PARENB; newtio.c_cflag |= PARODD; newtio.c_iflag |= (INPCK | ISTRIP); break; case 'e':case 'E': newtio.c_iflag |= (INPCK | ISTRIP); newtio.c_cflag |= PARENB; newtio.c_cflag &= ~PARODD; break;case 'n':case 'N': newtio.c_cflag &= ~PARENB; break;default:break;} /*设置波特率*/ switch( nSpeed ) { case 2400: cfsetispeed(&newtio, B2400); cfsetospeed(&newtio, B2400); break; case 4800: cfsetispeed(&newtio, B4800); cfsetospeed(&newtio, B4800); break; case 9600: cfsetispeed(&newtio, B9600); cfsetospeed(&newtio, B9600); break; case 115200: cfsetispeed(&newtio, B115200); cfsetospeed(&newtio, B115200); break; case 460800: cfsetispeed(&newtio, B460800); cfsetospeed(&newtio, B460800); break; default: cfsetispeed(&newtio, B9600); cfsetospeed(&newtio, B9600); break; } if( nStop == 1 ) newtio.c_cflag &=  ~CSTOPB; else if ( nStop == 2 ) newtio.c_cflag |=  CSTOPB; newtio.c_cc[VTIME]  = 0; newtio.c_cc[VMIN] = 0; tcflush(fd,TCIFLUSH); if((tcsetattr(fd,TCSANOW,&newtio))!=0) { perror("com set error"); return -1; } printf("set done!\n"); return 0; 
}int uart_close(int fd)
{assert(fd);close(fd);return 0;
}
int send_data(int  fd, char *send_buffer,int length)
{length=write(fd,send_buffer,length*sizeof(unsigned char));return length;
}
int recv_data(int fd, char* recv_buffer,int length)
{length=read(fd,recv_buffer,length);return length;
}float a[17];void ParseData(char chr)
{static char chrBuf[100];static unsigned char chrCnt=0;static char sData[100];unsigned char i;time_t now;chrBuf[chrCnt++]=chr;if (chrCnt<52) return;if (( (chrBuf[0]&0x50)!=0x50 )){printf("Error:%x %x\r\n",chrBuf[0],chrBuf[1]);memcpy(&chrBuf[0],&chrBuf[1],51);chrCnt--;return;}memcpy(&sData[0],&chrBuf[0],52);switch(chrBuf[0]){case 0x50:if ((sData[49] * 256.0 * 256.0 + sData[50] * 256.0 + sData[51] - 1000000) * 0.001==128)     //校验{a[0] = (sData[1] * 256.0 * 256.0 + sData[2] * 256.0 + sData[3] - 1000000) * 0.001;    //gx   开始解析串口数据a[1] = (sData[4] * 256.0 * 256.0 + sData[5] * 256.0 + sData[6] - 1000000) * 0.001;a[2] = (sData[7] * 256.0 * 256.0 + sData[8] * 256.0 + sData[9] - 1000000) * 0.001;a[3] = (sData[10] * 256.0 * 256.0 + sData[11] * 256.0 + sData[12] - 1000000) * 0.001;  //axa[4] = (sData[13] * 256.0 * 256.0 + sData[14] * 256.0 + sData[15] - 1000000) * 0.001;a[5] = (sData[16] * 256.0 * 256.0 + sData[17] * 256.0 + sData[18] - 1000000) * 0.001;a[6] = (sData[19] * 256.0 * 256.0 + sData[20] * 256.0 + sData[21] - 1000000) * 0.001; //mxa[7] = (sData[22] * 256.0 * 256.0 + sData[23] * 256.0 + sData[24] - 1000000) * 0.001;a[8] = (sData[25] * 256.0 * 256.0 + sData[26] * 256.0 + sData[27] - 1000000) * 0.001;a[9]  = (sData[28] * 256.0 * 256.0 + sData[29] * 256.0 + sData[30] - 1000000) * 0.001; //rolla[10] = (sData[31] * 256.0 * 256.0 + sData[32] * 256.0 + sData[33] - 1000000) * 0.001; //pitcha[11] = (sData[34] * 256.0 * 256.0 + sData[35] * 256.0 + sData[36] - 1000000) * 0.001;  //rawa[12] = (sData[37] * 256.0 * 256.0 + sData[38] * 256.0 + sData[39] - 1000000) * 0.001;   //q0a[13] = (sData[40] * 256.0 * 256.0 + sData[41] * 256.0 + sData[42] - 1000000) * 0.001;  //q1a[14] = (sData[43] * 256.0 * 256.0 + sData[44] * 256.0 + sData[45] - 1000000) * 0.001;  //q2a[15] = (sData[46] * 256.0 * 256.0 + sData[47] * 256.0 + sData[48] - 1000000) * 0.001;  //q3 }  time(&now);printf("\r\nT:%s a:%6.3f %6.3f %6.3f ",asctime(localtime(&now)),a[0],a[1],a[2]);  //输出加速度   可以自己照这行增加其他数据输出printf("\r\nT:%s a:%6.3f %6.3f %6.3f ",asctime(localtime(&now)),a[9],a[10],a[11]);  //输出欧拉角break;}		chrCnt=0;		
}int main(void)
{char r_buf[1024];bzero(r_buf,1024);fd = uart_open(fd,"/dev/ttyUSB0");/*串口号/dev/ttySn,USB口号/dev/ttyUSBn */ if(fd == -1){fprintf(stderr,"uart_open error\n");exit(EXIT_FAILURE);}if(uart_set(fd,BAUD,8,'N',1) == -1){fprintf(stderr,"uart set failed!\n");exit(EXIT_FAILURE);}FILE *fp;fp = fopen("Record.txt","w");while(1){ret = recv_data(fd,r_buf,44);if(ret == -1){fprintf(stderr,"uart read failed!\n");exit(EXIT_FAILURE);}for (int i=0;i<ret;i++) {fprintf(fp,"%2X ",r_buf[i]);ParseData(r_buf[i]);}usleep(1000);}ret = uart_close(fd);if(ret == -1){fprintf(stderr,"uart_close error\n");exit(EXIT_FAILURE);}exit(EXIT_SUCCESS);
}

4、即可在树莓中取得陀螺仪数据

终端中的Desktop文件夹即为桌面

编辑：gcc Uart901Demo.cpp -o Uart901Demo

运行：./ Uart901Demo