LSM9DS1.cpp

00001 /******************************************************************************
00002 SFE_LSM9DS1.cpp
00003 SFE_LSM9DS1 Library Source File
00004 Jim Lindblom @ SparkFun Electronics
00005 Original Creation Date: February 27, 2015
00006 https://github.com/sparkfun/LSM9DS1_Breakout
00007 
00008 This file implements all functions of the LSM9DS1 class. Functions here range
00009 from higher level stuff, like reading/writing LSM9DS1 registers to low-level,
00010 hardware reads and writes. Both SPI and I2C handler functions can be found
00011 towards the bottom of this file.
00012 
00013 Development environment specifics:
00014     IDE: Arduino 1.6
00015     Hardware Platform: Arduino Uno
00016     LSM9DS1 Breakout Version: 1.0
00017 
00018 This code is beerware; if you see me (or any other SparkFun employee) at the
00019 local, and you've found our code helpful, please buy us a round!
00020 
00021 Distributed as-is; no warranty is given.
00022 ******************************************************************************/
00023 
00024 #include "LSM9DS1.h"
00025 #include "LSM9DS1_Registers.h"
00026 #include "LSM9DS1_Types.h"
00027 //#include <Wire.h> // Wire library is used for I2C
00028 //#include <SPI.h>  // SPI library is used for...SPI.
00029 
00030 //#if defined(ARDUINO) && ARDUINO >= 100
00031 //  #include "Arduino.h"
00032 //#else
00033 //  #include "WProgram.h"
00034 //#endif
00035 
00036 #define LSM9DS1_COMMUNICATION_TIMEOUT 1000
00037 
00038 float magSensitivity[4] = {0.00014, 0.00029, 0.00043, 0.00058};
00039 
00040 LSM9DS1::LSM9DS1(PinName sda, PinName scl, uint8_t xgAddr, uint8_t mAddr)
00041     :i2c(sda, scl)
00042 {
00043     init(IMU_MODE_I2C, xgAddr, mAddr); // dont know about 0xD6 or 0x3B
00044 }
00045 /*
00046 LSM9DS1::LSM9DS1()
00047 {
00048     init(IMU_MODE_I2C, LSM9DS1_AG_ADDR(1), LSM9DS1_M_ADDR(1));
00049 }
00050 
00051 LSM9DS1::LSM9DS1(interface_mode interface, uint8_t xgAddr, uint8_t mAddr)
00052 {
00053     init(interface, xgAddr, mAddr);
00054 }
00055 */
00056 
00057 void LSM9DS1::init(interface_mode interface, uint8_t xgAddr, uint8_t mAddr)
00058 {
00059     settings.device.commInterface = interface;
00060     settings.device.agAddress = xgAddr;
00061     settings.device.mAddress = mAddr;
00062 
00063     settings.gyro.enabled = true;
00064     settings.gyro.enableX = true;
00065     settings.gyro.enableY = true;
00066     settings.gyro.enableZ = true;
00067     // gyro scale can be 245, 500, or 2000
00068     settings.gyro.scale = 245;
00069     // gyro sample rate: value between 1-6
00070     // 1 = 14.9    4 = 238
00071     // 2 = 59.5    5 = 476
00072     // 3 = 119     6 = 952
00073     settings.gyro.sampleRate = 6;
00074     // gyro cutoff frequency: value between 0-3
00075     // Actual value of cutoff frequency depends
00076     // on sample rate.
00077     settings.gyro.bandwidth = 0;
00078     settings.gyro.lowPowerEnable = false;
00079     settings.gyro.HPFEnable = false;
00080     // Gyro HPF cutoff frequency: value between 0-9
00081     // Actual value depends on sample rate. Only applies
00082     // if gyroHPFEnable is true.
00083     settings.gyro.HPFCutoff = 0;
00084     settings.gyro.flipX = false;
00085     settings.gyro.flipY = false;
00086     settings.gyro.flipZ = false;
00087     settings.gyro.orientation = 0;
00088     settings.gyro.latchInterrupt = true;
00089 
00090     settings.accel.enabled = true;
00091     settings.accel.enableX = true;
00092     settings.accel.enableY = true;
00093     settings.accel.enableZ = true;
00094     // accel scale can be 2, 4, 8, or 16
00095     settings.accel.scale = 2;
00096     // accel sample rate can be 1-6
00097     // 1 = 10 Hz    4 = 238 Hz
00098     // 2 = 50 Hz    5 = 476 Hz
00099     // 3 = 119 Hz   6 = 952 Hz
00100     settings.accel.sampleRate = 6;
00101     // Accel cutoff freqeuncy can be any value between -1 - 3. 
00102     // -1 = bandwidth determined by sample rate
00103     // 0 = 408 Hz   2 = 105 Hz
00104     // 1 = 211 Hz   3 = 50 Hz
00105     settings.accel.bandwidth = -1;
00106     settings.accel.highResEnable = false;
00107     // accelHighResBandwidth can be any value between 0-3
00108     // LP cutoff is set to a factor of sample rate
00109     // 0 = ODR/50    2 = ODR/9
00110     // 1 = ODR/100   3 = ODR/400
00111     settings.accel.highResBandwidth = 0;
00112 
00113     settings.mag.enabled = true;
00114     // mag scale can be 4, 8, 12, or 16
00115     settings.mag.scale = 4;
00116     // mag data rate can be 0-7
00117     // 0 = 0.625 Hz  4 = 10 Hz
00118     // 1 = 1.25 Hz   5 = 20 Hz
00119     // 2 = 2.5 Hz    6 = 40 Hz
00120     // 3 = 5 Hz      7 = 80 Hz
00121     settings.mag.sampleRate = 7;
00122     settings.mag.tempCompensationEnable = false;
00123     // magPerformance can be any value between 0-3
00124     // 0 = Low power mode      2 = high performance
00125     // 1 = medium performance  3 = ultra-high performance
00126     settings.mag.XYPerformance = 3;
00127     settings.mag.ZPerformance = 3;
00128     settings.mag.lowPowerEnable = false;
00129     // magOperatingMode can be 0-2
00130     // 0 = continuous conversion
00131     // 1 = single-conversion
00132     // 2 = power down
00133     settings.mag.operatingMode = 0;
00134 
00135     settings.temp.enabled = true;
00136     for (int i=0; i<3; i++)
00137     {
00138         gBias[i] = 0;
00139         aBias[i] = 0;
00140         mBias[i] = 0;
00141         gBiasRaw[i] = 0;
00142         aBiasRaw[i] = 0;
00143         mBiasRaw[i] = 0;
00144     }
00145     _autoCalc = false;
00146 }
00147 
00148 
00149 uint16_t LSM9DS1::begin()
00150 {
00151     //! Todo: don't use _xgAddress or _mAddress, duplicating memory
00152     _xgAddress = settings.device.agAddress;
00153     _mAddress = settings.device.mAddress;
00154     
00155     constrainScales();
00156     // Once we have the scale values, we can calculate the resolution
00157     // of each sensor. That's what these functions are for. One for each sensor
00158     calcgRes(); // Calculate DPS / ADC tick, stored in gRes variable
00159     calcmRes(); // Calculate Gs / ADC tick, stored in mRes variable
00160     calcaRes(); // Calculate g / ADC tick, stored in aRes variable
00161     
00162     // Now, initialize our hardware interface.
00163     if (settings.device.commInterface == IMU_MODE_I2C)  // If we're using I2C
00164         initI2C();  // Initialize I2C
00165     else if (settings.device.commInterface == IMU_MODE_SPI)     // else, if we're using SPI
00166         initSPI();  // Initialize SPI
00167         
00168     // To verify communication, we can read from the WHO_AM_I register of
00169     // each device. Store those in a variable so we can return them.
00170     uint8_t mTest = mReadByte(WHO_AM_I_M);      // Read the gyro WHO_AM_I
00171     uint8_t xgTest = xgReadByte(WHO_AM_I_XG);   // Read the accel/mag WHO_AM_I
00172     uint16_t whoAmICombined = (xgTest << 8) | mTest;
00173     
00174     if (whoAmICombined != ((WHO_AM_I_AG_RSP << 8) | WHO_AM_I_M_RSP))
00175         return 0;
00176     
00177     // Gyro initialization stuff:
00178     initGyro(); // This will "turn on" the gyro. Setting up interrupts, etc.
00179     
00180     // Accelerometer initialization stuff:
00181     initAccel(); // "Turn on" all axes of the accel. Set up interrupts, etc.
00182     
00183     // Magnetometer initialization stuff:
00184     initMag(); // "Turn on" all axes of the mag. Set up interrupts, etc.
00185 
00186     // Once everything is initialized, return the WHO_AM_I registers we read:
00187     return whoAmICombined;
00188 }
00189 
00190 void LSM9DS1::initGyro()
00191 {
00192     uint8_t tempRegValue = 0;
00193     
00194     // CTRL_REG1_G (Default value: 0x00)
00195     // [ODR_G2][ODR_G1][ODR_G0][FS_G1][FS_G0][0][BW_G1][BW_G0]
00196     // ODR_G[2:0] - Output data rate selection
00197     // FS_G[1:0] - Gyroscope full-scale selection
00198     // BW_G[1:0] - Gyroscope bandwidth selection
00199     
00200     // To disable gyro, set sample rate bits to 0. We'll only set sample
00201     // rate if the gyro is enabled.
00202     if (settings.gyro.enabled)
00203     {
00204         tempRegValue = (settings.gyro.sampleRate & 0x07) << 5;
00205     }
00206     switch (settings.gyro.scale)
00207     {
00208         case 500:
00209             tempRegValue |= (0x1 << 3);
00210             break;
00211         case 2000:
00212             tempRegValue |= (0x3 << 3);
00213             break;
00214         // Otherwise we'll set it to 245 dps (0x0 << 4)
00215     }
00216     tempRegValue |= (settings.gyro.bandwidth & 0x3);
00217     xgWriteByte(CTRL_REG1_G, tempRegValue);
00218     
00219     // CTRL_REG2_G (Default value: 0x00)
00220     // [0][0][0][0][INT_SEL1][INT_SEL0][OUT_SEL1][OUT_SEL0]
00221     // INT_SEL[1:0] - INT selection configuration
00222     // OUT_SEL[1:0] - Out selection configuration
00223     xgWriteByte(CTRL_REG2_G, 0x00); 
00224     
00225     // CTRL_REG3_G (Default value: 0x00)
00226     // [LP_mode][HP_EN][0][0][HPCF3_G][HPCF2_G][HPCF1_G][HPCF0_G]
00227     // LP_mode - Low-power mode enable (0: disabled, 1: enabled)
00228     // HP_EN - HPF enable (0:disabled, 1: enabled)
00229     // HPCF_G[3:0] - HPF cutoff frequency
00230     tempRegValue = settings.gyro.lowPowerEnable ? (1<<7) : 0;
00231     if (settings.gyro.HPFEnable)
00232     {
00233         tempRegValue |= (1<<6) | (settings.gyro.HPFCutoff & 0x0F);
00234     }
00235     xgWriteByte(CTRL_REG3_G, tempRegValue);
00236     
00237     // CTRL_REG4 (Default value: 0x38)
00238     // [0][0][Zen_G][Yen_G][Xen_G][0][LIR_XL1][4D_XL1]
00239     // Zen_G - Z-axis output enable (0:disable, 1:enable)
00240     // Yen_G - Y-axis output enable (0:disable, 1:enable)
00241     // Xen_G - X-axis output enable (0:disable, 1:enable)
00242     // LIR_XL1 - Latched interrupt (0:not latched, 1:latched)
00243     // 4D_XL1 - 4D option on interrupt (0:6D used, 1:4D used)
00244     tempRegValue = 0;
00245     if (settings.gyro.enableZ) tempRegValue |= (1<<5);
00246     if (settings.gyro.enableY) tempRegValue |= (1<<4);
00247     if (settings.gyro.enableX) tempRegValue |= (1<<3);
00248     if (settings.gyro.latchInterrupt) tempRegValue |= (1<<1);
00249     xgWriteByte(CTRL_REG4, tempRegValue);
00250     
00251     // ORIENT_CFG_G (Default value: 0x00)
00252     // [0][0][SignX_G][SignY_G][SignZ_G][Orient_2][Orient_1][Orient_0]
00253     // SignX_G - Pitch axis (X) angular rate sign (0: positive, 1: negative)
00254     // Orient [2:0] - Directional user orientation selection
00255     tempRegValue = 0;
00256     if (settings.gyro.flipX) tempRegValue |= (1<<5);
00257     if (settings.gyro.flipY) tempRegValue |= (1<<4);
00258     if (settings.gyro.flipZ) tempRegValue |= (1<<3);
00259     xgWriteByte(ORIENT_CFG_G, tempRegValue);
00260 }
00261 
00262 void LSM9DS1::initAccel()
00263 {
00264     uint8_t tempRegValue = 0;
00265     
00266     //  CTRL_REG5_XL (0x1F) (Default value: 0x38)
00267     //  [DEC_1][DEC_0][Zen_XL][Yen_XL][Zen_XL][0][0][0]
00268     //  DEC[0:1] - Decimation of accel data on OUT REG and FIFO.
00269     //      00: None, 01: 2 samples, 10: 4 samples 11: 8 samples
00270     //  Zen_XL - Z-axis output enabled
00271     //  Yen_XL - Y-axis output enabled
00272     //  Xen_XL - X-axis output enabled
00273     if (settings.accel.enableZ) tempRegValue |= (1<<5);
00274     if (settings.accel.enableY) tempRegValue |= (1<<4);
00275     if (settings.accel.enableX) tempRegValue |= (1<<3);
00276     
00277     xgWriteByte(CTRL_REG5_XL, tempRegValue);
00278     
00279     // CTRL_REG6_XL (0x20) (Default value: 0x00)
00280     // [ODR_XL2][ODR_XL1][ODR_XL0][FS1_XL][FS0_XL][BW_SCAL_ODR][BW_XL1][BW_XL0]
00281     // ODR_XL[2:0] - Output data rate & power mode selection
00282     // FS_XL[1:0] - Full-scale selection
00283     // BW_SCAL_ODR - Bandwidth selection
00284     // BW_XL[1:0] - Anti-aliasing filter bandwidth selection
00285     tempRegValue = 0;
00286     // To disable the accel, set the sampleRate bits to 0.
00287     if (settings.accel.enabled)
00288     {
00289         tempRegValue |= (settings.accel.sampleRate & 0x07) << 5;
00290     }
00291     switch (settings.accel.scale)
00292     {
00293         case 4:
00294             tempRegValue |= (0x2 << 3);
00295             break;
00296         case 8:
00297             tempRegValue |= (0x3 << 3);
00298             break;
00299         case 16:
00300             tempRegValue |= (0x1 << 3);
00301             break;
00302         // Otherwise it'll be set to 2g (0x0 << 3)
00303     }
00304     if (settings.accel.bandwidth >= 0)
00305     {
00306         tempRegValue |= (1<<2); // Set BW_SCAL_ODR
00307         tempRegValue |= (settings.accel.bandwidth & 0x03);
00308     }
00309     xgWriteByte(CTRL_REG6_XL, tempRegValue);
00310     
00311     // CTRL_REG7_XL (0x21) (Default value: 0x00)
00312     // [HR][DCF1][DCF0][0][0][FDS][0][HPIS1]
00313     // HR - High resolution mode (0: disable, 1: enable)
00314     // DCF[1:0] - Digital filter cutoff frequency
00315     // FDS - Filtered data selection
00316     // HPIS1 - HPF enabled for interrupt function
00317     tempRegValue = 0;
00318     if (settings.accel.highResEnable)
00319     {
00320         tempRegValue |= (1<<7); // Set HR bit
00321         tempRegValue |= (settings.accel.highResBandwidth & 0x3) << 5;
00322     }
00323     xgWriteByte(CTRL_REG7_XL, tempRegValue);
00324 }
00325 
00326 // This is a function that uses the FIFO to accumulate sample of accelerometer and gyro data, average
00327 // them, scales them to  gs and deg/s, respectively, and then passes the biases to the main sketch
00328 // for subtraction from all subsequent data. There are no gyro and accelerometer bias registers to store
00329 // the data as there are in the ADXL345, a precursor to the LSM9DS0, or the MPU-9150, so we have to
00330 // subtract the biases ourselves. This results in a more accurate measurement in general and can
00331 // remove errors due to imprecise or varying initial placement. Calibration of sensor data in this manner
00332 // is good practice.
00333 void LSM9DS1::calibrate(bool autoCalc)
00334 {  
00335     uint8_t samples = 0;
00336     int ii;
00337     int32_t aBiasRawTemp[3] = {0, 0, 0};
00338     int32_t gBiasRawTemp[3] = {0, 0, 0};
00339     
00340     // Turn on FIFO and set threshold to 32 samples
00341     enableFIFO(true);
00342     setFIFO(FIFO_THS, 0x1F);
00343     while (samples < 0x1F)
00344     {
00345         samples = (xgReadByte(FIFO_SRC) & 0x3F); // Read number of stored samples
00346     }
00347     for(ii = 0; ii < samples ; ii++) 
00348     {   // Read the gyro data stored in the FIFO
00349         readGyro();
00350         gBiasRawTemp[0] += gx;
00351         gBiasRawTemp[1] += gy;
00352         gBiasRawTemp[2] += gz;
00353         readAccel();
00354         aBiasRawTemp[0] += ax;
00355         aBiasRawTemp[1] += ay;
00356         aBiasRawTemp[2] += az - (int16_t)(1.f/aRes); // Assumes sensor facing up!
00357     }  
00358     for (ii = 0; ii < 3; ii++)
00359     {
00360         gBiasRaw[ii] = gBiasRawTemp[ii] / samples;
00361         gBias[ii] = calcGyro(gBiasRaw[ii]);
00362         aBiasRaw[ii] = aBiasRawTemp[ii] / samples;
00363         aBias[ii] = calcAccel(aBiasRaw[ii]);
00364     }
00365     
00366     enableFIFO(false);
00367     setFIFO(FIFO_OFF, 0x00);
00368     
00369     if (autoCalc) _autoCalc = true;
00370 }
00371 
00372 void LSM9DS1::calibrateMag(bool loadIn)
00373 {
00374     int i, j;
00375     int16_t magMin[3] = {0, 0, 0};
00376     int16_t magMax[3] = {0, 0, 0}; // The road warrior
00377     
00378     for (i=0; i<128; i++)
00379     {
00380         while (!magAvailable())
00381             ;
00382         readMag();
00383         int16_t magTemp[3] = {0, 0, 0};
00384         magTemp[0] = mx;        
00385         magTemp[1] = my;
00386         magTemp[2] = mz;
00387         for (j = 0; j < 3; j++)
00388         {
00389             if (magTemp[j] > magMax[j]) magMax[j] = magTemp[j];
00390             if (magTemp[j] < magMin[j]) magMin[j] = magTemp[j];
00391         }
00392     }
00393     for (j = 0; j < 3; j++)
00394     {
00395         mBiasRaw[j] = (magMax[j] + magMin[j]) / 2;
00396         mBias[j] = calcMag(mBiasRaw[j]);
00397         if (loadIn)
00398             magOffset(j, mBiasRaw[j]);
00399     }
00400     
00401 }
00402 void LSM9DS1::magOffset(uint8_t axis, int16_t offset)
00403 {
00404     if (axis > 2)
00405         return;
00406     uint8_t msb, lsb;
00407     msb = (offset & 0xFF00) >> 8;
00408     lsb = offset & 0x00FF;
00409     mWriteByte(OFFSET_X_REG_L_M + (2 * axis), lsb);
00410     mWriteByte(OFFSET_X_REG_H_M + (2 * axis), msb);
00411 }
00412 
00413 void LSM9DS1::initMag()
00414 {
00415     uint8_t tempRegValue = 0;
00416     
00417     // CTRL_REG1_M (Default value: 0x10)
00418     // [TEMP_COMP][OM1][OM0][DO2][DO1][DO0][0][ST]
00419     // TEMP_COMP - Temperature compensation
00420     // OM[1:0] - X & Y axes op mode selection
00421     //  00:low-power, 01:medium performance
00422     //  10: high performance, 11:ultra-high performance
00423     // DO[2:0] - Output data rate selection
00424     // ST - Self-test enable
00425     if (settings.mag.tempCompensationEnable) tempRegValue |= (1<<7);
00426     tempRegValue |= (settings.mag.XYPerformance & 0x3) << 5;
00427     tempRegValue |= (settings.mag.sampleRate & 0x7) << 2;
00428     mWriteByte(CTRL_REG1_M, tempRegValue);
00429     
00430     // CTRL_REG2_M (Default value 0x00)
00431     // [0][FS1][FS0][0][REBOOT][SOFT_RST][0][0]
00432     // FS[1:0] - Full-scale configuration
00433     // REBOOT - Reboot memory content (0:normal, 1:reboot)
00434     // SOFT_RST - Reset config and user registers (0:default, 1:reset)
00435     tempRegValue = 0;
00436     switch (settings.mag.scale)
00437     {
00438     case 8:
00439         tempRegValue |= (0x1 << 5);
00440         break;
00441     case 12:
00442         tempRegValue |= (0x2 << 5);
00443         break;
00444     case 16:
00445         tempRegValue |= (0x3 << 5);
00446         break;
00447     // Otherwise we'll default to 4 gauss (00)
00448     }
00449     mWriteByte(CTRL_REG2_M, tempRegValue); // +/-4Gauss
00450     
00451     // CTRL_REG3_M (Default value: 0x03)
00452     // [I2C_DISABLE][0][LP][0][0][SIM][MD1][MD0]
00453     // I2C_DISABLE - Disable I2C interace (0:enable, 1:disable)
00454     // LP - Low-power mode cofiguration (1:enable)
00455     // SIM - SPI mode selection (0:write-only, 1:read/write enable)
00456     // MD[1:0] - Operating mode
00457     //  00:continuous conversion, 01:single-conversion,
00458     //  10,11: Power-down
00459     tempRegValue = 0;
00460     if (settings.mag.lowPowerEnable) tempRegValue |= (1<<5);
00461     tempRegValue |= (settings.mag.operatingMode & 0x3);
00462     mWriteByte(CTRL_REG3_M, tempRegValue); // Continuous conversion mode
00463     
00464     // CTRL_REG4_M (Default value: 0x00)
00465     // [0][0][0][0][OMZ1][OMZ0][BLE][0]
00466     // OMZ[1:0] - Z-axis operative mode selection
00467     //  00:low-power mode, 01:medium performance
00468     //  10:high performance, 10:ultra-high performance
00469     // BLE - Big/little endian data
00470     tempRegValue = 0;
00471     tempRegValue = (settings.mag.ZPerformance & 0x3) << 2;
00472     mWriteByte(CTRL_REG4_M, tempRegValue);
00473     
00474     // CTRL_REG5_M (Default value: 0x00)
00475     // [0][BDU][0][0][0][0][0][0]
00476     // BDU - Block data update for magnetic data
00477     //  0:continuous, 1:not updated until MSB/LSB are read
00478     tempRegValue = 0;
00479     mWriteByte(CTRL_REG5_M, tempRegValue);
00480 }
00481 
00482 uint8_t LSM9DS1::accelAvailable()
00483 {
00484     uint8_t status = xgReadByte(STATUS_REG_1);
00485     
00486     return (status & (1<<0));
00487 }
00488 
00489 uint8_t LSM9DS1::gyroAvailable()
00490 {
00491     uint8_t status = xgReadByte(STATUS_REG_1);
00492     
00493     return ((status & (1<<1)) >> 1);
00494 }
00495 
00496 uint8_t LSM9DS1::tempAvailable()
00497 {
00498     uint8_t status = xgReadByte(STATUS_REG_1);
00499     
00500     return ((status & (1<<2)) >> 2);
00501 }
00502 
00503 uint8_t LSM9DS1::magAvailable(lsm9ds1_axis axis)
00504 {
00505     uint8_t status;
00506     status = mReadByte(STATUS_REG_M);
00507     
00508     return ((status & (1<<axis)) >> axis);
00509 }
00510 
00511 void LSM9DS1::readAccel()
00512 {
00513     uint8_t temp[6]; // We'll read six bytes from the accelerometer into temp   
00514     xgReadBytes(OUT_X_L_XL, temp, 6); // Read 6 bytes, beginning at OUT_X_L_XL
00515     ax = (temp[1] << 8) | temp[0]; // Store x-axis values into ax
00516     ay = (temp[3] << 8) | temp[2]; // Store y-axis values into ay
00517     az = (temp[5] << 8) | temp[4]; // Store z-axis values into az
00518     if (_autoCalc)
00519     {
00520         ax -= aBiasRaw[X_AXIS];
00521         ay -= aBiasRaw[Y_AXIS];
00522         az -= aBiasRaw[Z_AXIS];
00523     }
00524 }
00525 
00526 int16_t LSM9DS1::readAccel(lsm9ds1_axis axis)
00527 {
00528     uint8_t temp[2];
00529     int16_t value;
00530     xgReadBytes(OUT_X_L_XL + (2 * axis), temp, 2);
00531     value = (temp[1] << 8) | temp[0];
00532     
00533     if (_autoCalc)
00534         value -= aBiasRaw[axis];
00535     
00536     return value;
00537 }
00538 
00539 void LSM9DS1::readMag()
00540 {
00541     uint8_t temp[6]; // We'll read six bytes from the mag into temp 
00542     mReadBytes(OUT_X_L_M, temp, 6); // Read 6 bytes, beginning at OUT_X_L_M
00543     mx = (temp[1] << 8) | temp[0]; // Store x-axis values into mx
00544     my = (temp[3] << 8) | temp[2]; // Store y-axis values into my
00545     mz = (temp[5] << 8) | temp[4]; // Store z-axis values into mz
00546 }
00547 
00548 int16_t LSM9DS1::readMag(lsm9ds1_axis axis)
00549 {
00550     uint8_t temp[2];
00551     mReadBytes(OUT_X_L_M + (2 * axis), temp, 2);
00552     return (temp[1] << 8) | temp[0];
00553 }
00554 
00555 void LSM9DS1::readTemp()
00556 {
00557     uint8_t temp[2]; // We'll read two bytes from the temperature sensor into temp  
00558     xgReadBytes(OUT_TEMP_L, temp, 2); // Read 2 bytes, beginning at OUT_TEMP_L
00559     temperature = ((int16_t)temp[1] << 8) | temp[0];
00560 }
00561 
00562 void LSM9DS1::readGyro()
00563 {
00564     uint8_t temp[6]; // We'll read six bytes from the gyro into temp
00565     xgReadBytes(OUT_X_L_G, temp, 6); // Read 6 bytes, beginning at OUT_X_L_G
00566     gx = (temp[1] << 8) | temp[0]; // Store x-axis values into gx
00567     gy = (temp[3] << 8) | temp[2]; // Store y-axis values into gy
00568     gz = (temp[5] << 8) | temp[4]; // Store z-axis values into gz
00569     if (_autoCalc)
00570     {
00571         gx -= gBiasRaw[X_AXIS];
00572         gy -= gBiasRaw[Y_AXIS];
00573         gz -= gBiasRaw[Z_AXIS];
00574     }
00575 }
00576 
00577 int16_t LSM9DS1::readGyro(lsm9ds1_axis axis)
00578 {
00579     uint8_t temp[2];
00580     int16_t value;
00581     
00582     xgReadBytes(OUT_X_L_G + (2 * axis), temp, 2);
00583     
00584     value = (temp[1] << 8) | temp[0];
00585     
00586     if (_autoCalc)
00587         value -= gBiasRaw[axis];
00588     
00589     return value;
00590 }
00591 
00592 float LSM9DS1::calcGyro(int16_t gyro)
00593 {
00594     // Return the gyro raw reading times our pre-calculated DPS / (ADC tick):
00595     return gRes * gyro; 
00596 }
00597 
00598 float LSM9DS1::calcAccel(int16_t accel)
00599 {
00600     // Return the accel raw reading times our pre-calculated g's / (ADC tick):
00601     return aRes * accel;
00602 }
00603 
00604 float LSM9DS1::calcMag(int16_t mag)
00605 {
00606     // Return the mag raw reading times our pre-calculated Gs / (ADC tick):
00607     return mRes * mag;
00608 }
00609 
00610 void LSM9DS1::setGyroScale(uint16_t gScl)
00611 {
00612     // Read current value of CTRL_REG1_G:
00613     uint8_t ctrl1RegValue = xgReadByte(CTRL_REG1_G);
00614     // Mask out scale bits (3 & 4):
00615     ctrl1RegValue &= 0xE7;
00616     switch (gScl)
00617     {
00618         case 500:
00619             ctrl1RegValue |= (0x1 << 3);
00620             settings.gyro.scale = 500;
00621             break;
00622         case 2000:
00623             ctrl1RegValue |= (0x3 << 3);
00624             settings.gyro.scale = 2000;
00625             break;
00626         default: // Otherwise we'll set it to 245 dps (0x0 << 4)
00627             settings.gyro.scale = 245;
00628             break;
00629     }
00630     xgWriteByte(CTRL_REG1_G, ctrl1RegValue);
00631     
00632     calcgRes(); 
00633 }
00634 
00635 void LSM9DS1::setAccelScale(uint8_t aScl)
00636 {
00637     // We need to preserve the other bytes in CTRL_REG6_XL. So, first read it:
00638     uint8_t tempRegValue = xgReadByte(CTRL_REG6_XL);
00639     // Mask out accel scale bits:
00640     tempRegValue &= 0xE7;
00641     
00642     switch (aScl)
00643     {
00644         case 4:
00645             tempRegValue |= (0x2 << 3);
00646             settings.accel.scale = 4;
00647             break;
00648         case 8:
00649             tempRegValue |= (0x3 << 3);
00650             settings.accel.scale = 8;
00651             break;
00652         case 16:
00653             tempRegValue |= (0x1 << 3);
00654             settings.accel.scale = 16;
00655             break;
00656         default: // Otherwise it'll be set to 2g (0x0 << 3)
00657             settings.accel.scale = 2;
00658             break;
00659     }
00660     xgWriteByte(CTRL_REG6_XL, tempRegValue);
00661     
00662     // Then calculate a new aRes, which relies on aScale being set correctly:
00663     calcaRes();
00664 }
00665 
00666 void LSM9DS1::setMagScale(uint8_t mScl)
00667 {
00668     // We need to preserve the other bytes in CTRL_REG6_XM. So, first read it:
00669     uint8_t temp = mReadByte(CTRL_REG2_M);
00670     // Then mask out the mag scale bits:
00671     temp &= 0xFF^(0x3 << 5);
00672     
00673     switch (mScl)
00674     {
00675     case 8:
00676         temp |= (0x1 << 5);
00677         settings.mag.scale = 8;
00678         break;
00679     case 12:
00680         temp |= (0x2 << 5);
00681         settings.mag.scale = 12;
00682         break;
00683     case 16:
00684         temp |= (0x3 << 5);
00685         settings.mag.scale = 16;
00686         break;
00687     default: // Otherwise we'll default to 4 gauss (00)
00688         settings.mag.scale = 4;
00689         break;
00690     }   
00691     
00692     // And write the new register value back into CTRL_REG6_XM:
00693     mWriteByte(CTRL_REG2_M, temp);
00694     
00695     // We've updated the sensor, but we also need to update our class variables
00696     // First update mScale:
00697     //mScale = mScl;
00698     // Then calculate a new mRes, which relies on mScale being set correctly:
00699     calcmRes();
00700 }
00701 
00702 void LSM9DS1::setGyroODR(uint8_t gRate)
00703 {
00704     // Only do this if gRate is not 0 (which would disable the gyro)
00705     if ((gRate & 0x07) != 0)
00706     {
00707         // We need to preserve the other bytes in CTRL_REG1_G. So, first read it:
00708         uint8_t temp = xgReadByte(CTRL_REG1_G);
00709         // Then mask out the gyro ODR bits:
00710         temp &= 0xFF^(0x7 << 5);
00711         temp |= (gRate & 0x07) << 5;
00712         // Update our settings struct
00713         settings.gyro.sampleRate = gRate & 0x07;
00714         // And write the new register value back into CTRL_REG1_G:
00715         xgWriteByte(CTRL_REG1_G, temp);
00716     }
00717 }
00718 
00719 void LSM9DS1::setAccelODR(uint8_t aRate)
00720 {
00721     // Only do this if aRate is not 0 (which would disable the accel)
00722     if ((aRate & 0x07) != 0)
00723     {
00724         // We need to preserve the other bytes in CTRL_REG1_XM. So, first read it:
00725         uint8_t temp = xgReadByte(CTRL_REG6_XL);
00726         // Then mask out the accel ODR bits:
00727         temp &= 0x1F;
00728         // Then shift in our new ODR bits:
00729         temp |= ((aRate & 0x07) << 5);
00730         settings.accel.sampleRate = aRate & 0x07;
00731         // And write the new register value back into CTRL_REG1_XM:
00732         xgWriteByte(CTRL_REG6_XL, temp);
00733     }
00734 }
00735 
00736 void LSM9DS1::setMagODR(uint8_t mRate)
00737 {
00738     // We need to preserve the other bytes in CTRL_REG5_XM. So, first read it:
00739     uint8_t temp = mReadByte(CTRL_REG1_M);
00740     // Then mask out the mag ODR bits:
00741     temp &= 0xFF^(0x7 << 2);
00742     // Then shift in our new ODR bits:
00743     temp |= ((mRate & 0x07) << 2);
00744     settings.mag.sampleRate = mRate & 0x07;
00745     // And write the new register value back into CTRL_REG5_XM:
00746     mWriteByte(CTRL_REG1_M, temp);
00747 }
00748 
00749 void LSM9DS1::calcgRes()
00750 {
00751     gRes = ((float) settings.gyro.scale) / 32768.0f;
00752 }
00753 
00754 void LSM9DS1::calcaRes()
00755 {
00756     aRes = ((float) settings.accel.scale) / 32768.0f;
00757 }
00758 
00759 void LSM9DS1::calcmRes()
00760 {
00761     //mRes = ((float) settings.mag.scale) / 32768.0;
00762     switch (settings.mag.scale)
00763     {
00764     case 4:
00765         mRes = magSensitivity[0];
00766         break;
00767     case 8:
00768         mRes = magSensitivity[1];
00769         break;
00770     case 12:
00771         mRes = magSensitivity[2];
00772         break;
00773     case 16:
00774         mRes = magSensitivity[3];
00775         break;
00776     }
00777     
00778 }
00779 
00780 void LSM9DS1::configInt(interrupt_select interrupt, uint8_t generator,
00781                          h_lactive activeLow, pp_od pushPull)
00782 {
00783     // Write to INT1_CTRL or INT2_CTRL. [interupt] should already be one of
00784     // those two values.
00785     // [generator] should be an OR'd list of values from the interrupt_generators enum
00786     xgWriteByte(interrupt, generator);
00787     
00788     // Configure CTRL_REG8
00789     uint8_t temp;
00790     temp = xgReadByte(CTRL_REG8);
00791     
00792     if (activeLow) temp |= (1<<5);
00793     else temp &= ~(1<<5);
00794     
00795     if (pushPull) temp &= ~(1<<4);
00796     else temp |= (1<<4);
00797     
00798     xgWriteByte(CTRL_REG8, temp);
00799 }
00800 
00801 void LSM9DS1::configInactivity(uint8_t duration, uint8_t threshold, bool sleepOn)
00802 {
00803     uint8_t temp = 0;
00804     
00805     temp = threshold & 0x7F;
00806     if (sleepOn) temp |= (1<<7);
00807     xgWriteByte(ACT_THS, temp);
00808     
00809     xgWriteByte(ACT_DUR, duration);
00810 }
00811 
00812 uint8_t LSM9DS1::getInactivity()
00813 {
00814     uint8_t temp = xgReadByte(STATUS_REG_0);
00815     temp &= (0x10);
00816     return temp;
00817 }
00818 
00819 void LSM9DS1::configAccelInt(uint8_t generator, bool andInterrupts)
00820 {
00821     // Use variables from accel_interrupt_generator, OR'd together to create
00822     // the [generator]value.
00823     uint8_t temp = generator;
00824     if (andInterrupts) temp |= 0x80;
00825     xgWriteByte(INT_GEN_CFG_XL, temp);
00826 }
00827 
00828 void LSM9DS1::configAccelThs(uint8_t threshold, lsm9ds1_axis axis, uint8_t duration, bool wait)
00829 {
00830     // Write threshold value to INT_GEN_THS_?_XL.
00831     // axis will be 0, 1, or 2 (x, y, z respectively)
00832     xgWriteByte(INT_GEN_THS_X_XL + axis, threshold);
00833     
00834     // Write duration and wait to INT_GEN_DUR_XL
00835     uint8_t temp;
00836     temp = (duration & 0x7F);
00837     if (wait) temp |= 0x80;
00838     xgWriteByte(INT_GEN_DUR_XL, temp);
00839 }
00840 
00841 uint8_t LSM9DS1::getAccelIntSrc()
00842 {
00843     uint8_t intSrc = xgReadByte(INT_GEN_SRC_XL);
00844     
00845     // Check if the IA_XL (interrupt active) bit is set
00846     if (intSrc & (1<<6))
00847     {
00848         return (intSrc & 0x3F);
00849     }
00850     
00851     return 0;
00852 }
00853 
00854 void LSM9DS1::configGyroInt(uint8_t generator, bool aoi, bool latch)
00855 {
00856     // Use variables from accel_interrupt_generator, OR'd together to create
00857     // the [generator]value.
00858     uint8_t temp = generator;
00859     if (aoi) temp |= 0x80;
00860     if (latch) temp |= 0x40;
00861     xgWriteByte(INT_GEN_CFG_G, temp);
00862 }
00863 
00864 void LSM9DS1::configGyroThs(int16_t threshold, lsm9ds1_axis axis, uint8_t duration, bool wait)
00865 {
00866     uint8_t buffer[2];
00867     buffer[0] = (threshold & 0x7F00) >> 8;
00868     buffer[1] = (threshold & 0x00FF);
00869     // Write threshold value to INT_GEN_THS_?H_G and  INT_GEN_THS_?L_G.
00870     // axis will be 0, 1, or 2 (x, y, z respectively)
00871     xgWriteByte(INT_GEN_THS_XH_G + (axis * 2), buffer[0]);
00872     xgWriteByte(INT_GEN_THS_XH_G + 1 + (axis * 2), buffer[1]);
00873     
00874     // Write duration and wait to INT_GEN_DUR_XL
00875     uint8_t temp;
00876     temp = (duration & 0x7F);
00877     if (wait) temp |= 0x80;
00878     xgWriteByte(INT_GEN_DUR_G, temp);
00879 }
00880 
00881 uint8_t LSM9DS1::getGyroIntSrc()
00882 {
00883     uint8_t intSrc = xgReadByte(INT_GEN_SRC_G);
00884     
00885     // Check if the IA_G (interrupt active) bit is set
00886     if (intSrc & (1<<6))
00887     {
00888         return (intSrc & 0x3F);
00889     }
00890     
00891     return 0;
00892 }
00893 
00894 void LSM9DS1::configMagInt(uint8_t generator, h_lactive activeLow, bool latch)
00895 {
00896     // Mask out non-generator bits (0-4)
00897     uint8_t config = (generator & 0xE0);    
00898     // IEA bit is 0 for active-low, 1 for active-high.
00899     if (activeLow == INT_ACTIVE_HIGH) config |= (1<<2);
00900     // IEL bit is 0 for latched, 1 for not-latched
00901     if (!latch) config |= (1<<1);
00902     // As long as we have at least 1 generator, enable the interrupt
00903     if (generator != 0) config |= (1<<0);
00904     
00905     mWriteByte(INT_CFG_M, config);
00906 }
00907 
00908 void LSM9DS1::configMagThs(uint16_t threshold)
00909 {
00910     // Write high eight bits of [threshold] to INT_THS_H_M
00911     mWriteByte(INT_THS_H_M, uint8_t((threshold & 0x7F00) >> 8));
00912     // Write low eight bits of [threshold] to INT_THS_L_M
00913     mWriteByte(INT_THS_L_M, uint8_t(threshold & 0x00FF));
00914 }
00915 
00916 uint8_t LSM9DS1::getMagIntSrc()
00917 {
00918     uint8_t intSrc = mReadByte(INT_SRC_M);
00919     
00920     // Check if the INT (interrupt active) bit is set
00921     if (intSrc & (1<<0))
00922     {
00923         return (intSrc & 0xFE);
00924     }
00925     
00926     return 0;
00927 }
00928 
00929 void LSM9DS1::sleepGyro(bool enable)
00930 {
00931     uint8_t temp = xgReadByte(CTRL_REG9);
00932     if (enable) temp |= (1<<6);
00933     else temp &= ~(1<<6);
00934     xgWriteByte(CTRL_REG9, temp);
00935 }
00936 
00937 void LSM9DS1::enableFIFO(bool enable)
00938 {
00939     uint8_t temp = xgReadByte(CTRL_REG9);
00940     if (enable) temp |= (1<<1);
00941     else temp &= ~(1<<1);
00942     xgWriteByte(CTRL_REG9, temp);
00943 }
00944 
00945 void LSM9DS1::setFIFO(fifoMode_type fifoMode, uint8_t fifoThs)
00946 {
00947     // Limit threshold - 0x1F (31) is the maximum. If more than that was asked
00948     // limit it to the maximum.
00949     uint8_t threshold = fifoThs <= 0x1F ? fifoThs : 0x1F;
00950     xgWriteByte(FIFO_CTRL, ((fifoMode & 0x7) << 5) | (threshold & 0x1F));
00951 }
00952 
00953 uint8_t LSM9DS1::getFIFOSamples()
00954 {
00955     return (xgReadByte(FIFO_SRC) & 0x3F);
00956 }
00957 
00958 void LSM9DS1::constrainScales()
00959 {
00960     if ((settings.gyro.scale != 245) && (settings.gyro.scale != 500) && 
00961         (settings.gyro.scale != 2000))
00962     {
00963         settings.gyro.scale = 245;
00964     }
00965         
00966     if ((settings.accel.scale != 2) && (settings.accel.scale != 4) &&
00967         (settings.accel.scale != 8) && (settings.accel.scale != 16))
00968     {
00969         settings.accel.scale = 2;
00970     }
00971         
00972     if ((settings.mag.scale != 4) && (settings.mag.scale != 8) &&
00973         (settings.mag.scale != 12) && (settings.mag.scale != 16))
00974     {
00975         settings.mag.scale = 4;
00976     }
00977 }
00978 
00979 void LSM9DS1::xgWriteByte(uint8_t subAddress, uint8_t data)
00980 {
00981     // Whether we're using I2C or SPI, write a byte using the
00982     // gyro-specific I2C address or SPI CS pin.
00983     if (settings.device.commInterface == IMU_MODE_I2C) {
00984         I2CwriteByte(_xgAddress, subAddress, data);
00985     } else if (settings.device.commInterface == IMU_MODE_SPI) {
00986         SPIwriteByte(_xgAddress, subAddress, data);
00987     }
00988 }
00989 
00990 void LSM9DS1::mWriteByte(uint8_t subAddress, uint8_t data)
00991 {
00992     // Whether we're using I2C or SPI, write a byte using the
00993     // accelerometer-specific I2C address or SPI CS pin.
00994     if (settings.device.commInterface == IMU_MODE_I2C)
00995         return I2CwriteByte(_mAddress, subAddress, data);
00996     else if (settings.device.commInterface == IMU_MODE_SPI)
00997         return SPIwriteByte(_mAddress, subAddress, data);
00998 }
00999 
01000 uint8_t LSM9DS1::xgReadByte(uint8_t subAddress)
01001 {
01002     // Whether we're using I2C or SPI, read a byte using the
01003     // gyro-specific I2C address or SPI CS pin.
01004     if (settings.device.commInterface == IMU_MODE_I2C)
01005         return I2CreadByte(_xgAddress, subAddress);
01006     else if (settings.device.commInterface == IMU_MODE_SPI)
01007         return SPIreadByte(_xgAddress, subAddress);
01008     else
01009         return 0;
01010 }
01011 
01012 void LSM9DS1::xgReadBytes(uint8_t subAddress, uint8_t * dest, uint8_t count)
01013 {
01014     // Whether we're using I2C or SPI, read multiple bytes using the
01015     // gyro-specific I2C address or SPI CS pin.
01016     if (settings.device.commInterface == IMU_MODE_I2C) {
01017         I2CreadBytes(_xgAddress, subAddress, dest, count);
01018     } else if (settings.device.commInterface == IMU_MODE_SPI) {
01019         SPIreadBytes(_xgAddress, subAddress, dest, count);
01020     }
01021 }
01022 
01023 uint8_t LSM9DS1::mReadByte(uint8_t subAddress)
01024 {
01025     // Whether we're using I2C or SPI, read a byte using the
01026     // accelerometer-specific I2C address or SPI CS pin.
01027     if (settings.device.commInterface == IMU_MODE_I2C)
01028         return I2CreadByte(_mAddress, subAddress);
01029     else if (settings.device.commInterface == IMU_MODE_SPI)
01030         return SPIreadByte(_mAddress, subAddress);
01031     else
01032         return 0;
01033 }
01034 
01035 void LSM9DS1::mReadBytes(uint8_t subAddress, uint8_t * dest, uint8_t count)
01036 {
01037     // Whether we're using I2C or SPI, read multiple bytes using the
01038     // accelerometer-specific I2C address or SPI CS pin.
01039     if (settings.device.commInterface == IMU_MODE_I2C)
01040         I2CreadBytes(_mAddress, subAddress, dest, count);
01041     else if (settings.device.commInterface == IMU_MODE_SPI)
01042         SPIreadBytes(_mAddress, subAddress, dest, count);
01043 }
01044 
01045 void LSM9DS1::initSPI()
01046 {
01047     /* 
01048     pinMode(_xgAddress, OUTPUT);
01049     digitalWrite(_xgAddress, HIGH);
01050     pinMode(_mAddress, OUTPUT);
01051     digitalWrite(_mAddress, HIGH);
01052     
01053     SPI.begin();
01054     // Maximum SPI frequency is 10MHz, could divide by 2 here:
01055     SPI.setClockDivider(SPI_CLOCK_DIV2);
01056     // Data is read and written MSb first.
01057     SPI.setBitOrder(MSBFIRST);
01058     // Data is captured on rising edge of clock (CPHA = 0)
01059     // Base value of the clock is HIGH (CPOL = 1)
01060     SPI.setDataMode(SPI_MODE0);
01061     */
01062 }
01063 
01064 void LSM9DS1::SPIwriteByte(uint8_t csPin, uint8_t subAddress, uint8_t data)
01065 {
01066     /*
01067     digitalWrite(csPin, LOW); // Initiate communication
01068     
01069     // If write, bit 0 (MSB) should be 0
01070     // If single write, bit 1 should be 0
01071     SPI.transfer(subAddress & 0x3F); // Send Address
01072     SPI.transfer(data); // Send data
01073     
01074     digitalWrite(csPin, HIGH); // Close communication
01075     */
01076 }
01077 
01078 uint8_t LSM9DS1::SPIreadByte(uint8_t csPin, uint8_t subAddress)
01079 {
01080     uint8_t temp = 0;
01081     // Use the multiple read function to read 1 byte. 
01082     // Value is returned to `temp`.
01083     SPIreadBytes(csPin, subAddress, &temp, 1);
01084     return temp;
01085 }
01086 
01087 void LSM9DS1::SPIreadBytes(uint8_t csPin, uint8_t subAddress,
01088                             uint8_t * dest, uint8_t count)
01089 {
01090     // To indicate a read, set bit 0 (msb) of first byte to 1
01091     uint8_t rAddress = 0x80 | (subAddress & 0x3F);
01092     // Mag SPI port is different. If we're reading multiple bytes, 
01093     // set bit 1 to 1. The remaining six bytes are the address to be read
01094     if ((csPin == _mAddress) && count > 1)
01095         rAddress |= 0x40;
01096     
01097     /* 
01098     digitalWrite(csPin, LOW); // Initiate communication
01099     SPI.transfer(rAddress);
01100     for (int i=0; i<count; i++)
01101     {
01102         dest[i] = SPI.transfer(0x00); // Read into destination array
01103     }
01104     digitalWrite(csPin, HIGH); // Close communication
01105     */
01106 }
01107 
01108 void LSM9DS1::initI2C()
01109 {
01110     /* 
01111     Wire.begin();   // Initialize I2C library
01112     */
01113     
01114     //already initialized in constructor!
01115 }
01116 
01117 // Wire.h read and write protocols
01118 void LSM9DS1::I2CwriteByte(uint8_t address, uint8_t subAddress, uint8_t data)
01119 {
01120     /* 
01121     Wire.beginTransmission(address);  // Initialize the Tx buffer
01122     Wire.write(subAddress);           // Put slave register address in Tx buffer
01123     Wire.write(data);                 // Put data in Tx buffer
01124     Wire.endTransmission();           // Send the Tx buffer
01125     */
01126     char temp_data[2] = {subAddress, data};
01127     i2c.write(address, temp_data, 2);
01128 }
01129 
01130 uint8_t LSM9DS1::I2CreadByte(uint8_t address, uint8_t subAddress)
01131 {
01132     /* 
01133     int timeout = LSM9DS1_COMMUNICATION_TIMEOUT;
01134     uint8_t data; // `data` will store the register data    
01135     
01136     Wire.beginTransmission(address);         // Initialize the Tx buffer
01137     Wire.write(subAddress);                  // Put slave register address in Tx buffer
01138     Wire.endTransmission(true);             // Send the Tx buffer, but send a restart to keep connection alive
01139     Wire.requestFrom(address, (uint8_t) 1);  // Read one byte from slave register address 
01140     while ((Wire.available() < 1) && (timeout-- > 0))
01141         delay(1);
01142     
01143     if (timeout <= 0)
01144         return 255; //! Bad! 255 will be misinterpreted as a good value.
01145     
01146     data = Wire.read();                      // Fill Rx buffer with result
01147     return data;                             // Return data read from slave register
01148     */
01149     char data;
01150     char temp[1] = {subAddress};
01151     
01152     i2c.write(address, temp, 1);
01153     //i2c.write(address & 0xFE);
01154     temp[0] = 0x00;
01155     i2c.write(address, temp, 1);
01156     //i2c.write( address | 0x01);
01157     i2c.read(address, &data, 1);
01158     return data;
01159 }
01160 
01161 uint8_t LSM9DS1::I2CreadBytes(uint8_t address, uint8_t subAddress, uint8_t * dest, uint8_t count)
01162 {  
01163     /* 
01164     int timeout = LSM9DS1_COMMUNICATION_TIMEOUT;
01165     Wire.beginTransmission(address);   // Initialize the Tx buffer
01166     // Next send the register to be read. OR with 0x80 to indicate multi-read.
01167     Wire.write(subAddress | 0x80);     // Put slave register address in Tx buffer
01168 
01169     Wire.endTransmission(true);             // Send the Tx buffer, but send a restart to keep connection alive
01170     uint8_t i = 0;
01171     Wire.requestFrom(address, count);  // Read bytes from slave register address 
01172     while ((Wire.available() < count) && (timeout-- > 0))
01173         delay(1);
01174     if (timeout <= 0)
01175         return -1;
01176     
01177     for (int i=0; i<count;)
01178     {
01179         if (Wire.available())
01180         {
01181             dest[i++] = Wire.read();
01182         }
01183     }
01184     return count;
01185     */
01186     char temp = (char)subAddress;
01187     i2c.write(address, &temp, 1);
01188     i2c.read(address, (char*)dest, count);
01189 
01190     return count;
01191 }