Simple library for MAG3110 magenetometer as built into Avnet Wi-Go module
Dependents: Wi-Go-MagnetometerTest EE202A_HW1_MH serialtoxively mbed_nanosec_timer ... more
Revision 7:0f45239e157a, committed 2014-05-09
- Comitter:
- SomeRandomBloke
- Date:
- Fri May 09 18:01:36 2014 +0000
- Parent:
- 6:f510561f6107
- Parent:
- 5:f3abe901c33a
- Child:
- 8:d13d9ccddff7
- Commit message:
- merged pull request fro calXY
Changed in this revision
--- a/MAG3110.cpp Tue Dec 31 17:16:37 2013 +0000 +++ b/MAG3110.cpp Fri May 09 18:01:36 2014 +0000 @@ -5,14 +5,16 @@ /****************************************************************************** * Constructors ******************************************************************************/ -MAG3110::MAG3110(PinName sda, PinName scl): _i2c(sda, scl), - _i2c_address(0x1D), _pc(NULL), _debug(false) +MAG3110::MAG3110(PinName sda, PinName scl): _i2c(sda, scl), + _i2c_address(0x1d), _pc(NULL), _debug(false) + { begin(); } -MAG3110::MAG3110(PinName sda, PinName scl, Serial *pc): _i2c(sda, scl), - _i2c_address(0x1D), _pc(pc), _debug(true) +MAG3110::MAG3110(PinName sda, PinName scl, Serial *pc): _i2c(sda, scl), + _i2c_address(0x1d), _pc(pc), _debug(true) + { begin(); } @@ -26,7 +28,7 @@ _i2c.write(_i2c_address, cmd, 2); cmd[0] = MAG_CTRL_REG1; - cmd[1] = MAG_3110_SAMPLE80+MAG_3110_OVERSAMPLE2+MAG_3110_ACTIVE; + cmd[1] = MAG_3110_ACTIVE; _i2c.write(_i2c_address, cmd, 2); // No adjustment initially @@ -40,27 +42,34 @@ char cmd[1]; cmd[0] = regAddr; - _i2c.write(_i2c_address, cmd, 1); - + if(_i2c.write(_i2c_address, cmd, 1)) { + printf("MAG3110 write error\r\n"); + _i2c.stop(); + _i2c.start(); + } cmd[0] = 0x00; _i2c.read(_i2c_address, cmd, 1); return (int)( cmd[0]); } - // read a register per, pass first reg value, reading 2 bytes increments register // Reads MSB first then LSB int MAG3110::readVal(char regAddr) { char cmd[2]; - + int16_t t; cmd[0] = regAddr; - _i2c.write(_i2c_address, cmd, 1); + if(_i2c.write(_i2c_address, cmd, 1)) { + printf("MAG3110 write error\r\n"); + _i2c.stop(); + _i2c.start(); + } cmd[0] = 0x00; cmd[1] = 0x00; _i2c.read(_i2c_address, cmd, 2); - return (int)( (cmd[1]|(cmd[0] << 8))); //concatenate the MSB and LSB + t = (cmd[0] * 256) + (unsigned short) cmd[1]; + return ((int) t); //concatenate the MSB and LSB } @@ -78,6 +87,24 @@ *zVal = readVal(MAG_OUT_Z_MSB); } +void MAG3110::ReadXYZ(float * mag) +{ + int x, y, z; + x = readVal(MAG_OUT_X_MSB); + y = readVal(MAG_OUT_Y_MSB); + z = readVal(MAG_OUT_Z_MSB); + mag[0] = (float) x / 10.0; + mag[1] = (float) y / 10.0; + mag[2] = (float) z / 10.0; + +} + +void MAG3110::ReadXYZraw(int16_t * mag_raw) +{ + mag_raw[0] = readVal(MAG_OUT_X_MSB); + mag_raw[1] = readVal(MAG_OUT_Y_MSB); + mag_raw[2] = readVal(MAG_OUT_Z_MSB); +} void MAG3110::setCalibration(int minX, int maxX, int minY, int maxY ) {
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MAG3110.cpp.orig Fri May 09 18:01:36 2014 +0000 @@ -0,0 +1,118 @@ + +#include "MAG3110.h" +#include "mbed.h" + +/****************************************************************************** + * Constructors + ******************************************************************************/ +MAG3110::MAG3110(PinName sda, PinName scl): _i2c(sda, scl), + _i2c_address(0x1D), _pc(NULL), _debug(false) +{ + begin(); +} + +MAG3110::MAG3110(PinName sda, PinName scl, Serial *pc): _i2c(sda, scl), + _i2c_address(0x1D), _pc(pc), _debug(true) +{ + begin(); +} + +void MAG3110::begin() +{ + char cmd[2]; + + cmd[0] = MAG_CTRL_REG2; + cmd[1] = 0x80; + _i2c.write(_i2c_address, cmd, 2); + + cmd[0] = MAG_CTRL_REG1; + cmd[1] = MAG_3110_SAMPLE80+MAG_3110_OVERSAMPLE2+MAG_3110_ACTIVE; + _i2c.write(_i2c_address, cmd, 2); + + // No adjustment initially + _avgX = 0; + _avgY = 0; +} + +// Read a single byte form 8 bit register, return as int +int MAG3110::readReg(char regAddr) +{ + char cmd[1]; + + cmd[0] = regAddr; + _i2c.write(_i2c_address, cmd, 1); + + cmd[0] = 0x00; + _i2c.read(_i2c_address, cmd, 1); + return (int)( cmd[0]); +} + + +// read a register per, pass first reg value, reading 2 bytes increments register +// Reads MSB first then LSB +int MAG3110::readVal(char regAddr) +{ + char cmd[2]; + + cmd[0] = regAddr; + _i2c.write(_i2c_address, cmd, 1); + + cmd[0] = 0x00; + cmd[1] = 0x00; + _i2c.read(_i2c_address, cmd, 2); + return (int)( (cmd[1]|(cmd[0] << 8))); //concatenate the MSB and LSB +} + + +float MAG3110::getHeading() +{ + int xVal = readVal(MAG_OUT_X_MSB); + int yVal = readVal(MAG_OUT_Y_MSB); + return (atan2((double)(yVal - _avgY),(double)(xVal - _avgX)))*180/PI; +} + +void MAG3110::getValues(int *xVal, int *yVal, int *zVal) +{ + *xVal = readVal(MAG_OUT_X_MSB); + *yVal = readVal(MAG_OUT_Y_MSB); + *zVal = readVal(MAG_OUT_Z_MSB); +} + + +void MAG3110::setCalibration(int minX, int maxX, int minY, int maxY ) +{ + _avgX=(maxX+minX)/2; + _avgY=(maxY+minY)/2; +} + + + +void MAG3110::calXY(PinName pin, int activeValue ) +{ + DigitalIn calPin(pin); + int tempXmax, tempXmin, tempYmax, tempYmin, newX, newY; + + + // Wait for Button Press and Release before beginning calibration + while(calPin != activeValue) {} + while(calPin == activeValue) {} + + + // Read initial values of magnetomoter - read it here to create a slight delay for calPin to settle + tempXmax = tempXmin = readVal(MAG_OUT_X_MSB); + tempYmax = tempYmin = readVal(MAG_OUT_Y_MSB); + + // Update min and max values until calPin asserted again + while(calPin != activeValue) { + newX = readVal(MAG_OUT_X_MSB); + newY = readVal(MAG_OUT_Y_MSB); + if (newX > tempXmax) tempXmax = newX; + if (newX < tempXmin) tempXmin = newX; + if (newY > tempYmax) tempYmax = newY; + if (newY < tempYmin) tempYmin = newY; + } + + setCalibration( tempXmin, tempXmax, tempYmin, tempYmax ); + +} +
--- a/MAG3110.h Tue Dec 31 17:16:37 2013 +0000 +++ b/MAG3110.h Fri May 09 18:01:36 2014 +0000 @@ -117,6 +117,19 @@ * @return heading in degrees */ float getHeading(); + + /** + * Perform a read on the X, Y and Z values, converted to microteslas. + * @paran mag Pointer to the 3 element array whare the results will be placed + */ + void ReadXYZ(float * mag); + + /** + * Perform a read on the raw X, Y and Z values. + * @paran mag Pointer to the 3 element array whare the results will be placed + */ + void ReadXYZraw(int16_t * mag_raw); + /** * Perform a read on the X, Y and Z values. * @param xVal Pointer to X value @@ -145,6 +158,7 @@ Serial *_pc; bool _debug; int _avgX, _avgY; + int x, y, z; }; #endif