Allows for reading accelerometer, gyroscope, and magnetometer data from an LSM9DS0 IMU device
Dependents: uVGA_4180 uLCD_4180_mini ECE4781_Project
Diff: main.cpp
- Revision:
- 0:1b975a6ae539
- Child:
- 3:7ede465deae1
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/main.cpp Tue Oct 21 18:11:45 2014 +0000 @@ -0,0 +1,157 @@ +#include "LSM9DS0.h" +#include "mbed.h" + +// SDO_XM and SDO_G are both grounded, so our addresses are: +#define LSM9DS0_XM 0x1E // Would be 0x1E if SDO_XM is LOW +#define LSM9DS0_G 0x6A // Would be 0x6A if SDO_G is LOW + +// Create an instance of the LSM9DS0 library called `dof` the +// parameters for this constructor are: +// pins,[gyro I2C address],[xm I2C add.] +LSM9DS0 dof(p28, p27, LSM9DS0_G, LSM9DS0_XM); +DigitalIn DReady(p23); + +Serial pc(USBTX, USBRX); // tx, rx + +bool printMag = true; +bool printAccel = true; +bool printGyro = true; +bool printHead = true; + +void setup() +{ + pc.baud(115200); // Start serial at 115200 bps + // Use the begin() function to initialize the LSM9DS0 library. + // You can either call it with no parameters (the easy way): + uint16_t status = dof.begin(); + + // Or call it with declarations for sensor scales and data rates: + //uint16_t status = dof.begin(dof.G_SCALE_2000DPS, + // dof.A_SCALE_6G, dof.M_SCALE_2GS); + + // begin() returns a 16-bit value which includes both the gyro + // and accelerometers WHO_AM_I response. You can check this to + // make sure communication was successful. + pc.printf("LSM9DS0 WHO_AM_I's returned: 0x"); + pc.printf("%x\n",status); + pc.printf("Should be 0x49D4\n"); + pc.printf("\n"); +} + +void printGyro() { + dof.readGyro(); + + pc.printf("G: "); + + pc.printf("%2f",dof.calcGyro(dof.gx)); + pc.printf(", "); + pc.printf("%2f",dof.calcGyro(dof.gy)); + pc.printf(", "); + pc.printf("%2f\n",dof.calcGyro(dof.gz)); +} + +void printAccel() { + dof.readAccel(); + + pc.printf("A: "); + + pc.printf("%2f",dof.calcAccel(dof.ax)); + pc.printf(", "); + pc.printf("%2f",dof.calcAccel(dof.ay)); + pc.printf(", "); + pc.printf("%2f\n",dof.calcAccel(dof.az)); + +} + +void printMag() { + dof.readMag(); + + pc.printf("M: "); + + pc.printf("%2f",dof.calcMag(dof.mx)); + pc.printf(", "); + pc.printf("%2f",dof.calcMag(dof.my)); + pc.printf(", "); + pc.printf("%2f\n",dof.calcMag(dof.mz)); +} + +// Here's a fun function to calculate your heading, using Earth's +// magnetic field. +// It only works if the sensor is flat (z-axis normal to Earth). +// Additionally, you may need to add or subtract a declination +// angle to get the heading normalized to your location. +// See: http://www.ngdc.noaa.gov/geomag/declination.shtml +void printHeading(float hx, float hy) +{ + float heading; + + if (hy > 0) heading = 90 - (atan(hx / hy) * (180 / 3.14)); + else if (hy < 0) heading = - (atan(hx / hy) * (180 / 3.14)); + else // hy = 0 + { + if (hx < 0) heading = 180; + else heading = 0; + } + + pc.printf("Heading: "); + pc.printf("%2f\n",heading); +} + +// Another fun function that does calculations based on the +// acclerometer data. This function will print your LSM9DS0's +// orientation -- it's roll and pitch angles. +void printOrientation(float x, float y, float z) +{ + float pitch, roll; + + pitch = atan2(x, sqrt(y * y) + (z * z)); + roll = atan2(y, sqrt(x * x) + (z * z)); + pitch *= 180.0 / 3.14; + roll *= 180.0 / 3.14; + + pc.printf("Pitch, Roll: "); + pc.printf("%2f",pitch); + pc.printf(", "); + pc.printf("%2f\n",roll); +} + +void readData() { + // To read from the device, you must first call the + // readMag(), readAccel(), and readGyro() functions. + // When this exits, it'll update the appropriate + // variables ([mx, my, mz], [ax, ay, az], [gx, gy, gz]) + // with the most current data. + + dof.readMag(); + dof.readAccel(); + dof.readGyro(); +} + +void loop() { + // Loop until the Data Ready signal goes high + while (!Dready) {} + + readData(); + + if (printGyro) printGyro(); // Print "G: gx, gy, gz" + if (printAccel) printAccel(); // Print "A: ax, ay, az" + if (printMag) printMag(); // Print "M: mx, my, mz" + + // Print the heading and orientation for fun! + if (printHead) printHeading((float) dof.mx, (float) dof.my); + //printOrientation(dof.calcAccel(dof.ax), dof.calcAccel(dof.ay), + // dof.calcAccel(dof.az)); + pc.printf("\n"); + + wait(2); +} + + +int main() +{ + setup(); + while (true) + { + loop(); + } +}