This is a simple project using the Orientation Sensor MPU6050.
This is a 6-axis device containing 3 accelerometers and 3 gyroscopes.
The driver is written directly in Annex script but it rely on the internal fusion algorithm to compute the 3 orientation angles (pitch, roll and yaw).
The files in attachment contains all the required files for this project.
Even if not drawn on the schematics, the code drives also an OLED display that can simply connected in parallel on the same I2C pins.
As the MPU6050 doesn't contains the magnetometers (it is only 6 axis), there will be a little drift on the yaw axis.
Wiring
The output window
The Code
CODE: mpu6050.bas
' MPU6050 Test program
' cicciocb 2018
' the values shown are in 'g' for the accelerometers
' in °/sec for the gyros and in °C for the temperature
' refer to datasheet : https://www.invensense.com/wp-content/uploads/2015/02/MPU-6000-Register-Map1.pdf
MPU6050SlaveAddress = &h68
AccelScaleFactor = 32768 / 2 ' 2G full scale -- sensitivity scale factor respective to full scale setting provided in datasheet
GyroScaleFactor = 32768 / 500' 500 °/sec full scale
MPU6050_REG_SMPLRT_DIV = &h19
MPU6050_REG_CONFIG = &h1A
MPU6050_REG_GYRO_CONFIG = &h1B
MPU6050_REG_ACCEL_CONFIG = &h1C
MPU6050_REG_FIFO_EN = &h23
MPU6050_REG_INT_ENABLE = &h38
MPU6050_REG_ACCEL_XOUT_H = &h3B
MPU6050_REG_SIGNAL_PATH_RESET = &h68
MPU6050_REG_USER_CTRL = &h6A
MPU6050_REG_PWR_MGMT_1 = &h6B
MPU6050_REG_PWR_MGMT_2 = &h6C
MPU6050_REG_WHO_AM_I = &h75
' parameters for the MPU6050
dim IMU_data(20)
AccelX = 0 : AccelY = 0 : AccelZ = 0
GyroX = 0: GyroY = 0: GyroZ = 0
Temperature = 0
' parameters for 6 DoF sensor fusion calculations
pitch = 0 : yaw = 0 : roll = 0
GyroMeasError = PI * (5.0 / 180.0) ' gyroscope measurement error in rads/s (start at 60 deg/s), then reduce after ~10 s to 3
beta = sqr(3.0 / 4.0) * GyroMeasError ' compute beta
GyroMeasDrift = PI * (2.0 / 180.0) ' gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
zeta = sqr(3.0 / 4.0) * GyroMeasDrift ' compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value
fusion.init
fusion.beta = beta
fusion.zeta = zeta
onUrlMessage message
'opens the html page
jscall "window.location = 'mpu6050_demo.html'"
i2c.setup 4,5
oled.init 1
oled.print 0,0, "DEMO MPU6050 SENSOR"
'check the presence of the MPU6050
ident = i2c.ReadRegByte(MPU6050SlaveAddress, MPU6050_REG_WHO_AM_I)
if ident <> MPU6050SlaveAddress then print "MPU6050 not found." : end
'initialise the module
MPU6050_Ini
for j = 1 to 100000
i2c.readregarray MPU6050SlaveAddress, MPU6050_REG_ACCEL_XOUT_H, 14, IMU_data() ' read all registers in one shot
'extract all the parameters from the buffer
extract_param AccelX, 0
extract_param AccelY, 2
extract_param AccelZ, 4
extract_param GyroX, 8
extract_param GyroY, 10
extract_param GyroZ, 12
extract_param Temperature, 6
'scale all the parameters in Engineering Unit
AccelX = AccelX/AccelScaleFactor
AccelY = AccelY/AccelScaleFactor
AccelZ = AccelZ/AccelScaleFactor
GyroX = GyroX/GyroScaleFactor
GyroY = GyroY/GyroScaleFactor
GyroZ = GyroZ/GyroScaleFactor
Temperature = Temperature/340 + 36.53
fusion.Madgwick AccelX, AccelY, AccelZ, (GyroX * Pi/180), (GyroY * Pi/180), -(GyroZ * Pi/180)
pitch = fusion.angle(1)
roll = -fusion.angle(2)
yaw = fusion.angle(3)
print
print str$(pitch, "%3.1f"), str$(roll, "%3.1f"), str$(yaw, "%3.1f")
oled.print 0, 20, "Pitch:"+ str$(pitch,"%4.2f")+ " ", 0
oled.print 0, 35, "Roll:"+ str$(roll,"%4.2f")+ " ", 0
oled.print 0, 50, "Yaw:"+ str$(yaw,"%4.2f")+ " ", 0
next j
end
message:
UrlMsgReturn str$(pitch) + "," + str$(roll) + "," + str$(yaw) + ",1"
return
'------------------------------------------------------------
'extract a parameter from the buffer at the given address
'correct the sign of the value using the Most significant bit
sub extract_param(ret, address)
ret = (IMU_data(address) <<8) + IMU_data(address+1)
if ret > 32768 then ret = ret - 65536
end sub
'configuration of the MPU6050
sub MPU6050_Ini
pause 150
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_PWR_MGMT_1, &h01 'PLL with X axis gyroscope reference
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_PWR_MGMT_2, &h00 ' no sensors standby
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_SMPLRT_DIV, 7 ' sample rate = 8Khz / (1 + 7) -> 1KHz
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_CONFIG, &h01 ' bandwith 5Hz (delay 19msec) Fs 1Kz
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_GYRO_CONFIG, &h08 'set +/-500 degree/second full scale
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_ACCEL_CONFIG, &h00 ' set +/- 2g full scale
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_FIFO_EN, &h00 ' fifo disabled
'enables the Data Ready interrupt, which occurs each
'time a write operation to all of the sensor registers has been completed.
'put a led on the pin INT to see the sample rate
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_INT_ENABLE, &h01
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_SIGNAL_PATH_RESET, &h07 ' reset sensors
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_USER_CTRL, &h00 ' do not reset sensor registers (put 1 if required)
'i2c.WriteRegByte MPU6050SlaveAddress, MPU9250_INT_PIN_CFG, &h02 ' enable bypass mode
end sub
' cicciocb 2018
' the values shown are in 'g' for the accelerometers
' in °/sec for the gyros and in °C for the temperature
' refer to datasheet : https://www.invensense.com/wp-content/uploads/2015/02/MPU-6000-Register-Map1.pdf
MPU6050SlaveAddress = &h68
AccelScaleFactor = 32768 / 2 ' 2G full scale -- sensitivity scale factor respective to full scale setting provided in datasheet
GyroScaleFactor = 32768 / 500' 500 °/sec full scale
MPU6050_REG_SMPLRT_DIV = &h19
MPU6050_REG_CONFIG = &h1A
MPU6050_REG_GYRO_CONFIG = &h1B
MPU6050_REG_ACCEL_CONFIG = &h1C
MPU6050_REG_FIFO_EN = &h23
MPU6050_REG_INT_ENABLE = &h38
MPU6050_REG_ACCEL_XOUT_H = &h3B
MPU6050_REG_SIGNAL_PATH_RESET = &h68
MPU6050_REG_USER_CTRL = &h6A
MPU6050_REG_PWR_MGMT_1 = &h6B
MPU6050_REG_PWR_MGMT_2 = &h6C
MPU6050_REG_WHO_AM_I = &h75
' parameters for the MPU6050
dim IMU_data(20)
AccelX = 0 : AccelY = 0 : AccelZ = 0
GyroX = 0: GyroY = 0: GyroZ = 0
Temperature = 0
' parameters for 6 DoF sensor fusion calculations
pitch = 0 : yaw = 0 : roll = 0
GyroMeasError = PI * (5.0 / 180.0) ' gyroscope measurement error in rads/s (start at 60 deg/s), then reduce after ~10 s to 3
beta = sqr(3.0 / 4.0) * GyroMeasError ' compute beta
GyroMeasDrift = PI * (2.0 / 180.0) ' gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
zeta = sqr(3.0 / 4.0) * GyroMeasDrift ' compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value
fusion.init
fusion.beta = beta
fusion.zeta = zeta
onUrlMessage message
'opens the html page
jscall "window.location = 'mpu6050_demo.html'"
i2c.setup 4,5
oled.init 1
oled.print 0,0, "DEMO MPU6050 SENSOR"
'check the presence of the MPU6050
ident = i2c.ReadRegByte(MPU6050SlaveAddress, MPU6050_REG_WHO_AM_I)
if ident <> MPU6050SlaveAddress then print "MPU6050 not found." : end
'initialise the module
MPU6050_Ini
for j = 1 to 100000
i2c.readregarray MPU6050SlaveAddress, MPU6050_REG_ACCEL_XOUT_H, 14, IMU_data() ' read all registers in one shot
'extract all the parameters from the buffer
extract_param AccelX, 0
extract_param AccelY, 2
extract_param AccelZ, 4
extract_param GyroX, 8
extract_param GyroY, 10
extract_param GyroZ, 12
extract_param Temperature, 6
'scale all the parameters in Engineering Unit
AccelX = AccelX/AccelScaleFactor
AccelY = AccelY/AccelScaleFactor
AccelZ = AccelZ/AccelScaleFactor
GyroX = GyroX/GyroScaleFactor
GyroY = GyroY/GyroScaleFactor
GyroZ = GyroZ/GyroScaleFactor
Temperature = Temperature/340 + 36.53
fusion.Madgwick AccelX, AccelY, AccelZ, (GyroX * Pi/180), (GyroY * Pi/180), -(GyroZ * Pi/180)
pitch = fusion.angle(1)
roll = -fusion.angle(2)
yaw = fusion.angle(3)
print str$(pitch, "%3.1f"), str$(roll, "%3.1f"), str$(yaw, "%3.1f")
oled.print 0, 20, "Pitch:"+ str$(pitch,"%4.2f")+ " ", 0
oled.print 0, 35, "Roll:"+ str$(roll,"%4.2f")+ " ", 0
oled.print 0, 50, "Yaw:"+ str$(yaw,"%4.2f")+ " ", 0
next j
end
message:
UrlMsgReturn str$(pitch) + "," + str$(roll) + "," + str$(yaw) + ",1"
return
'------------------------------------------------------------
'extract a parameter from the buffer at the given address
'correct the sign of the value using the Most significant bit
sub extract_param(ret, address)
ret = (IMU_data(address) <<8) + IMU_data(address+1)
if ret > 32768 then ret = ret - 65536
end sub
'configuration of the MPU6050
sub MPU6050_Ini
pause 150
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_PWR_MGMT_1, &h01 'PLL with X axis gyroscope reference
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_PWR_MGMT_2, &h00 ' no sensors standby
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_SMPLRT_DIV, 7 ' sample rate = 8Khz / (1 + 7) -> 1KHz
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_CONFIG, &h01 ' bandwith 5Hz (delay 19msec) Fs 1Kz
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_GYRO_CONFIG, &h08 'set +/-500 degree/second full scale
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_ACCEL_CONFIG, &h00 ' set +/- 2g full scale
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_FIFO_EN, &h00 ' fifo disabled
'enables the Data Ready interrupt, which occurs each
'time a write operation to all of the sensor registers has been completed.
'put a led on the pin INT to see the sample rate
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_INT_ENABLE, &h01
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_SIGNAL_PATH_RESET, &h07 ' reset sensors
i2c.WriteRegByte MPU6050SlaveAddress, MPU6050_REG_USER_CTRL, &h00 ' do not reset sensor registers (put 1 if required)
'i2c.WriteRegByte MPU6050SlaveAddress, MPU9250_INT_PIN_CFG, &h02 ' enable bypass mode
end sub
