BMI055编程

BMI055与其他imu不同的地方是他的加速度硬件单元和陀螺仪硬件单元是分开独立的（两个不同的CHIPID），他们使用两个不同的片选，地址空间重叠。

一般的imu如 mpu6050,mpu6500,mpu9250,imu160等等都是加速度硬件单元和陀螺仪硬件单元一体，一个片选，地址不重叠。
所以BMI055的编程稍微复杂点，需要两个spi，如果共用GPIO的话那就至少需要一个IO口模拟的spi（1硬件1模拟或者2个模拟）。
代码如下：

#include "imu.h"void IMU_init(void){       u8 imu_data[12] = {0};    u16 imu_dat[6] = {0};    my_spi_io_init();    IMU_config(RANGE_2G,RANGE_2000);    while(1){//for test      IMU_Read(imu_data);      //acc      imu_dat[0] = (u16)imu_data[1]<<4 | imu_data[0]>>4;      imu_dat[1] = (u16)imu_data[3]<<4 | imu_data[2]>>4;      imu_dat[2] = (u16)imu_data[5]<<4 | imu_data[4]>>4;      //gyr      imu_dat[3] = imu_data[7]<<8  | imu_data[6];      imu_dat[4] = imu_data[9]<<8  | imu_data[8];      imu_dat[5] = imu_data[11]<<8 | imu_data[10];      asm("nop");    }}void IMU_Read(u8 *buf){    u8 i = 0;    u8 addr = 0x00;     addr |= 0x80;//read    //read acc data    SPI_CS_ACC = 0;    addr |= ACC_X_LSB_REG;    My_SPI_ReadWriteByte(addr);    for(i=0;i<6;i++){        *(buf+i) = My_SPI_ReadWriteByte(0);             asm("nop");    }    SPI_CS_ACC = 1;    //read gyr data    SPI_CS_GYR = 0;    addr |= GYR_X_LSB_REG;    My_SPI_ReadWriteByte(addr);    for(i=6; i<12; i++){        *(buf+i) = My_SPI_ReadWriteByte(0);             asm("nop");    }    SPI_CS_GYR = 1;}//   for(i=0;i<6;i++){//        SPI_CS_ACC=0;//        addr |= (ACC_X_LSB_REG+i);//        RW_SPI(addr);//        acc[i] = RW_SPI(0);       //        SPI_CS_ACC=1;//    } u8 My_SPI_ReadWriteByte(u8 val){    u8 i;    for(i=0;i<8;i++){         SPI_CLK = 0;        asm("nop"); asm("nop"); asm("nop");        //write        if(val & 0x80)                                            SPI_DO = 1;        else            SPI_DO = 0;        val <<= 1;        SPI_CLK = 1;        asm("nop"); asm("nop"); asm("nop");        //read        if(SPI_DI)            val |= 1;                                           }    SPI_CLK = 0;        return val;}u8  IMU_config(u8 acc_range,u8 gyr_range){    u8 res = 0;    u8 reg = 0x00;//REG_CHIPID     reg |= 0x80;//read        //Check ACC CHIP_ID    SPI_CS_ACC=0;    My_SPI_ReadWriteByte(reg);              res = My_SPI_ReadWriteByte(0);          SPI_CS_ACC=1;    if(res != ACC_CHIP_ID){        res = 1;    }    //Check GYR CHIP_ID    SPI_CS_GYR=0;    My_SPI_ReadWriteByte(reg);              res = My_SPI_ReadWriteByte(0);          SPI_CS_GYR=1;    if(res != GYR_CHIP_ID){        res = 2;    }       //Config ACC RANGE    SPI_CS_ACC=0;    My_SPI_ReadWriteByte(IMU_CONFIG_REG);//write                My_SPI_ReadWriteByte(acc_range);    SPI_CS_ACC=1;    SPI_CS_ACC=0;    My_SPI_ReadWriteByte(reg | IMU_CONFIG_REG);             res = My_SPI_ReadWriteByte(0);//read reg     if(res != acc_range){//Write failed.        res = 3;    }    SPI_CS_ACC=1;       //Config GYR RANGE    SPI_CS_GYR=0;    My_SPI_ReadWriteByte(IMU_CONFIG_REG);//write                My_SPI_ReadWriteByte(gyr_range);    SPI_CS_GYR=1;    SPI_CS_GYR=0;    My_SPI_ReadWriteByte(reg | IMU_CONFIG_REG);             res = My_SPI_ReadWriteByte(0);//read reg     if(res != gyr_range){//Write failed.        res = 4;    }else{        res = 0;//ok    }    SPI_CS_GYR=1;     return res;}  void my_spi_io_init(void){    GPIO_InitTypeDef GPIO_InitStructure;            RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB, ENABLE );//PORTB奀笘妏夔     GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_13 |  GPIO_Pin_15;//sck,miso    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;    GPIO_Init(GPIOB, &GPIO_InitStructure);        GPIO_SetBits(GPIOB, GPIO_Pin_13 |  GPIO_Pin_15);      GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_14 ;    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;   //MOSI  input    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;    GPIO_Init(GPIOB, &GPIO_InitStructure);    //PA4: CS_ACC    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;    GPIO_Init(GPIOA, &GPIO_InitStructure);    GPIO_SetBits(GPIOA,GPIO_Pin_4);    //PB12: CS_GYR    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;    GPIO_Init(GPIOB, &GPIO_InitStructure);    GPIO_SetBits(GPIOB,GPIO_Pin_12);    }