Samuel Lin / MPU9250

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Dependents:   Task_1_BallRidingbot_KeepingStationCatching_layingDown_1230

Fork of MPU9250_SPI by Mu kylong

Files at this revision

API Documentation at this revision

Revision 2:f274ea3bced9, committed 2014-06-21

Comitter:
kylongmu
Date:
Sat Jun 21 12:39:55 2014 +0000
Parent:
1:f738165e54f0
Child:
3:f4fa24cc247d
Commit message:
Modify read function.

Changed in this revision

MPU9250.cpp Show annotated file Show diff for this revision Revisions of this file
MPU9250.h Show annotated file Show diff for this revision Revisions of this file 
--- a/MPU9250.cpp	Sat Jun 21 11:55:36 2014 +0000
+++ b/MPU9250.cpp	Sat Jun 21 12:39:55 2014 +0000
@@ -17,7 +17,11 @@
     wait_us(50);
     return temp_val;
 }
-void mpu9250_spi::ReadRegs( unsigned int ReadAddr, unsigned int *ReadBuf, unsigned int Bytes )
+unsigned int  mpu9250_spi::ReadReg( uint8_t WriteAddr, uint8_t WriteData )
+{
+    return WriteReg(WriteAddr | READ_FLAG,WriteData);
+}
+void mpu9250_spi::ReadRegs( uint8_t ReadAddr, uint8_t *ReadBuf, unsigned int Bytes )
 {
     unsigned int  i = 0;
 
@@ -29,19 +33,6 @@
     wait_us(50);
 }
 
-/*
-void mpu9250_spi::ReadReg( u8 ReadAddr, u8 *ReadData )
-{
-    select();
-    response=spi.write(MPUREG_USER_CTRL);
-    response=spi.write(BIT_I2C_IF_DIS);
-    deselect();
-  IMU_CSM = 0;
-  SPI_WriteByte(SPIx, 0x80 | ReadAddr);
-  *ReadData = SPI_ReadByte(SPIx);
-  IMU_CSM = 1;
-}
-*/
 /*-----------------------------------------------------------------------------------------------
                                     INITIALIZATION
 usage: call this function at startup, giving the sample rate divider (raging from 0 to 255) and
@@ -196,29 +187,26 @@
 2 -> Z axis
 returns the value in Gs
 -----------------------------------------------------------------------------------------------*/
-float mpu9250_spi::read_acc(int axis){
-    uint8_t responseH,responseL;
+void mpu9250_spi::read_acc()
+{
+    uint8_t response[2];
     int16_t bit_data;
     float data;
-    select();
-    switch (axis){
-        case 0:
-        responseH=spi.write(MPUREG_ACCEL_XOUT_H | READ_FLAG);
-        break;
-        case 1:
-        responseH=spi.write(MPUREG_ACCEL_YOUT_H | READ_FLAG);
-        break;
-        case 2:
-        responseH=spi.write(MPUREG_ACCEL_ZOUT_H | READ_FLAG);
-        break;
-    }
-    responseH=spi.write(0x00);
-    responseL=spi.write(0x00);
-    bit_data=((int16_t)responseH<<8)|responseL;
+
+    ReadRegs(MPUREG_ACCEL_XOUT_H,response,2);
+    bit_data=((int16_t)response[0]<<8)|response[1];
     data=(float)bit_data;
-    data=data/acc_divider;
-    deselect();
-    return data;
+    accelerometer_data[0]=data/acc_divider;
+
+    ReadRegs(MPUREG_ACCEL_YOUT_H,response,2);
+    bit_data=((int16_t)response[0]<<8)|response[1];
+    data=(float)bit_data;
+    accelerometer_data[1]=data/acc_divider;
+
+    ReadRegs(MPUREG_ACCEL_ZOUT_H,response,2);
+    bit_data=((int16_t)response[0]<<8)|response[1];
+    data=(float)bit_data;
+    accelerometer_data[2]=data/acc_divider;
 }
 
 /*-----------------------------------------------------------------------------------------------
@@ -229,29 +217,26 @@
 2 -> Z axis
 returns the value in Degrees per second
 -----------------------------------------------------------------------------------------------*/
-float mpu9250_spi::read_rot(int axis){
-    uint8_t responseH,responseL;
+void mpu9250_spi::read_rot()
+{
+    uint8_t response[2];
     int16_t bit_data;
     float data;
-    select();
-    switch (axis){
-        case 0:
-        responseH=spi.write(MPUREG_GYRO_XOUT_H | READ_FLAG);
-        break;
-        case 1:
-        responseH=spi.write(MPUREG_GYRO_YOUT_H | READ_FLAG);
-        break;
-        case 2:
-        responseH=spi.write(MPUREG_GYRO_ZOUT_H | READ_FLAG);
-        break;
-    }
-    responseH=spi.write(0x00);
-    responseL=spi.write(0x00);
-    bit_data=((int16_t)responseH<<8)|responseL;
+
+    ReadRegs(MPUREG_GYRO_XOUT_H,response,2);
+    bit_data=((int16_t)response[0]<<8)|response[1];
     data=(float)bit_data;
-    data=data/gyro_divider;
-    deselect();
-    return data;
+    gyroscope_data[0]=data/gyro_divider;
+
+    ReadRegs(MPUREG_GYRO_YOUT_H,response,2);
+    bit_data=((int16_t)response[0]<<8)|response[1];
+    data=(float)bit_data;
+    gyroscope_data[1]=data/gyro_divider;
+
+    ReadRegs(MPUREG_GYRO_ZOUT_H,response,2);
+    bit_data=((int16_t)response[0]<<8)|response[1];
+    data=(float)bit_data;
+    gyroscope_data[2]=data/gyro_divider;
 }
 
 /*-----------------------------------------------------------------------------------------------
@@ -260,14 +245,12 @@
 returns the value in °C
 -----------------------------------------------------------------------------------------------*/
 float mpu9250_spi::read_temp(){
-    uint8_t responseH,responseL;
+    uint8_t response[2];
     int16_t bit_data;
     float data;
-    select();
-    responseH=spi.write(MPUREG_TEMP_OUT_H | READ_FLAG);
-    responseH=spi.write(0x00);
-    responseL=spi.write(0x00);
-    bit_data=((int16_t)responseH<<8)|responseL;
+    ReadRegs(MPUREG_TEMP_OUT_H,response,2);
+
+    bit_data=((int16_t)response[0]<<8)|response[1];
     data=(float)bit_data;
     data=(data/340)+36.53;
     deselect();
@@ -282,45 +265,23 @@
 2 -> Z axis
 returns Factory Trim value
 -----------------------------------------------------------------------------------------------*/
-int mpu9250_spi::calib_acc(int axis){
-    uint8_t responseH,responseL,calib_data;
+void mpu9250_spi::calib_acc()
+{
+    uint8_t response[4];
     int temp_scale;
     //READ CURRENT ACC SCALE
     temp_scale=WriteReg(MPUREG_ACCEL_CONFIG|READ_FLAG, 0x00);
     set_acc_scale(BITS_FS_8G);
-    //ENABLE SELF TEST
-    temp_scale=WriteReg(MPUREG_ACCEL_CONFIG, 0x80>>axis);
+    //ENABLE SELF TEST need modify
+    //temp_scale=WriteReg(MPUREG_ACCEL_CONFIG, 0x80>>axis);
 
-    select();
-    responseH=spi.write(MPUREG_SELF_TEST_X|READ_FLAG);
-    switch(axis){
-        case 0:
-            responseH=spi.write(0x00);
-            responseL=spi.write(0x00);
-            responseL=spi.write(0x00);
-            responseL=spi.write(0x00);
-            calib_data=((responseH&11100000)>>3)|((responseL&00110000)>>4);
-        break;
-        case 1:
-            responseH=spi.write(0x00);
-            responseH=spi.write(0x00);
-            responseL=spi.write(0x00);
-            responseL=spi.write(0x00);
-            calib_data=((responseH&11100000)>>3)|((responseL&00001100)>>2);
-        break;
-        case 2:
-            responseH=spi.write(0x00);
-            responseH=spi.write(0x00);
-            responseH=spi.write(0x00);
-            responseL=spi.write(0x00);
-            calib_data=((responseH&11100000)>>3)|((responseL&00000011));
-        break;
-    }
-    deselect();
-    wait(0.01);
+    ReadRegs(MPUREG_SELF_TEST_X,response,4);
+    calib_data[0]=((response[0]&11100000)>>3)|((response[3]&00110000)>>4);
+    calib_data[1]=((response[1]&11100000)>>3)|((response[3]&00001100)>>2);
+    calib_data[2]=((response[2]&11100000)>>3)|((response[3]&00000011));
+
     set_acc_scale(temp_scale);
-    return calib_data;
-} 
+}
 
 /*-----------------------------------------------------------------------------------------------
                                 SPI SELECT AND DESELECT

--- a/MPU9250.h	Sat Jun 21 11:55:36 2014 +0000
+++ b/MPU9250.h	Sat Jun 21 12:39:55 2014 +0000
@@ -49,14 +49,15 @@
   public:
     mpu9250_spi(SPI& _spi, PinName _cs);
     unsigned int WriteReg( uint8_t WriteAddr, uint8_t WriteData );
-    void ReadRegs( unsigned int ReadAddr, unsigned int *ReadBuf, unsigned int Bytes );
+    unsigned int ReadReg( uint8_t WriteAddr, uint8_t WriteData );
+    void ReadRegs( uint8_t ReadAddr, uint8_t *ReadBuf, unsigned int Bytes );
 
     bool init(int sample_rate_div,int low_pass_filter);
-    float read_acc(int axis);
-    float read_rot(int axis);
+    void read_acc();
+    void read_rot();
     unsigned int set_gyro_scale(int scale);
     unsigned int set_acc_scale(int scale);
-    int calib_acc(int axis);
+    void calib_acc();
     float read_temp();
     void select();
     void deselect();
@@ -65,6 +66,10 @@
     float acc_divider;
     float gyro_divider;
     
+    int calib_data[3];
+    float gyroscope_data[3];
+    float accelerometer_data[3];
+    
   private:
     PinName _CS_pin;
     PinName _SO_pin;