Tyler Weaver / ITG3200

Modified getOffset for calibrating Thermal Drift coefficients.

Dependents:   9Dof_unit_testing

Fork of ITG3200 by James Watanabe

Modified to make getOffset() function easier to use.

ITG3200.cpp@13:e886466d7d67, 2012-11-06 (annotated)

Committer:
tylerjw
Date:
Tue Nov 06 17:35:14 2012 +0000
Revision:
13:e886466d7d67
Parent:
12:d624e9c6dae7
Child:
14:e4bf80188ba7
int changed to int16_t

Who changed what in which revision?

UserRevisionLine numberNew contents of line
gltest26 1:9bef044f45ad 1 /**
gltest26 4:155c44407af5 2 * @file ITG3200.cpp
tylerjw 11:9a354f34d8e3 3 * @author Tyler Weaver
gltest26 1:9bef044f45ad 4 *
gltest26 1:9bef044f45ad 5 * @section LICENSE
gltest26 1:9bef044f45ad 6 *
gltest26 1:9bef044f45ad 7 * Copyright (c) 2010 ARM Limited
gltest26 1:9bef044f45ad 8 *
gltest26 1:9bef044f45ad 9 * Permission is hereby granted, free of charge, to any person obtaining a copy
gltest26 1:9bef044f45ad 10 * of this software and associated documentation files (the "Software"), to deal
gltest26 1:9bef044f45ad 11 * in the Software without restriction, including without limitation the rights
gltest26 1:9bef044f45ad 12 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
gltest26 1:9bef044f45ad 13 * copies of the Software, and to permit persons to whom the Software is
gltest26 1:9bef044f45ad 14 * furnished to do so, subject to the following conditions:
gltest26 1:9bef044f45ad 15 *
gltest26 1:9bef044f45ad 16 * The above copyright notice and this permission notice shall be included in
gltest26 1:9bef044f45ad 17 * all copies or substantial portions of the Software.
gltest26 1:9bef044f45ad 18 *
gltest26 1:9bef044f45ad 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
gltest26 1:9bef044f45ad 20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
gltest26 1:9bef044f45ad 21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
gltest26 1:9bef044f45ad 22 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
gltest26 1:9bef044f45ad 23 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
gltest26 1:9bef044f45ad 24 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
gltest26 1:9bef044f45ad 25 * THE SOFTWARE.
gltest26 1:9bef044f45ad 26 *
gltest26 1:9bef044f45ad 27 * @section DESCRIPTION
gltest26 1:9bef044f45ad 28 *
tylerjw 11:9a354f34d8e3 29 * Modified version of Aaron Berk's library.
gltest26 1:9bef044f45ad 30 * ITG-3200 triple axis, digital interface, gyroscope.
gltest26 1:9bef044f45ad 31 *
gltest26 1:9bef044f45ad 32 * Datasheet:
gltest26 1:9bef044f45ad 33 *
gltest26 1:9bef044f45ad 34 * http://invensense.com/mems/gyro/documents/PS-ITG-3200-00-01.4.pdf
gltest26 1:9bef044f45ad 35 */
gltest26 1:9bef044f45ad 36
gltest26 1:9bef044f45ad 37 #include "ITG3200.h"
gltest26 8:ac0365ab3cef 38 #include <new>
gltest26 1:9bef044f45ad 39
tylerjw 11:9a354f34d8e3 40 ITG3200::ITG3200(PinName sda, PinName scl, bool fastmode) : calibSamples(0), i2c_(*reinterpret_cast<I2C*>(i2cRaw))
tylerjw 11:9a354f34d8e3 41 {
gltest26 8:ac0365ab3cef 42 // Placement new to avoid additional heap memory allocation.
gltest26 8:ac0365ab3cef 43 new(i2cRaw) I2C(sda, scl);
gltest26 1:9bef044f45ad 44
gltest26 3:eea9733ca427 45 offset[0] = offset[1] = offset[2] = 0;
gltest26 3:eea9733ca427 46
tylerjw 11:9a354f34d8e3 47 if(fastmode) {
gltest26 7:43b936a53b64 48 //400kHz, fast mode.
gltest26 7:43b936a53b64 49 i2c_.frequency(400000);
tylerjw 11:9a354f34d8e3 50 } else
gltest26 7:43b936a53b64 51 i2c_.frequency(100000);
tylerjw 11:9a354f34d8e3 52 }
tylerjw 11:9a354f34d8e3 53
tylerjw 11:9a354f34d8e3 54 ITG3200::~ITG3200()
tylerjw 11:9a354f34d8e3 55 {
gltest26 8:ac0365ab3cef 56 // If the I2C object is initialized in the buffer in this object, call destructor of it.
gltest26 8:ac0365ab3cef 57 if(&i2c_ == reinterpret_cast<I2C*>(&i2cRaw))
gltest26 8:ac0365ab3cef 58 reinterpret_cast<I2C*>(&i2cRaw)->~I2C();
gltest26 8:ac0365ab3cef 59 }
gltest26 8:ac0365ab3cef 60
tylerjw 11:9a354f34d8e3 61 void ITG3200::init()
tylerjw 11:9a354f34d8e3 62 {
gltest26 1:9bef044f45ad 63 //Set FS_SEL to 0x03 for proper operation.
gltest26 1:9bef044f45ad 64 //See datasheet for details.
gltest26 1:9bef044f45ad 65 char tx[2];
gltest26 1:9bef044f45ad 66 tx[0] = DLPF_FS_REG;
gltest26 1:9bef044f45ad 67 //FS_SEL bits sit in bits 4 and 3 of DLPF_FS register.
gltest26 1:9bef044f45ad 68 tx[1] = 0x03 << 3;
tylerjw 11:9a354f34d8e3 69
gltest26 1:9bef044f45ad 70 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
tylerjw 12:d624e9c6dae7 71
tylerjw 12:d624e9c6dae7 72 const float offset[3] = {99.5, -45.0, -29.7}; // taken from itg3200.xls curve fit test
tylerjw 12:d624e9c6dae7 73 const float slope[3] = {-1.05, 0.95, 0.47};
gltest26 1:9bef044f45ad 74
tylerjw 12:d624e9c6dae7 75 setCalibrationCurve(offset, slope);
tylerjw 12:d624e9c6dae7 76 setLpBandwidth(LPFBW_5HZ); // lowest rate low-pass filter
gltest26 1:9bef044f45ad 77 }
gltest26 1:9bef044f45ad 78
tylerjw 11:9a354f34d8e3 79 void ITG3200::setCalibrationCurve(const float offset[3], const float slope[3])
tylerjw 11:9a354f34d8e3 80 {
tylerjw 11:9a354f34d8e3 81 if(offset) {
gltest26 9:05396b551a9a 82 for(int i = 0; i < 3; i++)
gltest26 9:05396b551a9a 83 this->foffset[i] = offset[i];
gltest26 9:05396b551a9a 84 }
tylerjw 11:9a354f34d8e3 85 if(slope) {
gltest26 9:05396b551a9a 86 for(int i = 0; i < 3; i++)
gltest26 9:05396b551a9a 87 this->slope[i] = slope[i];
gltest26 9:05396b551a9a 88 }
gltest26 9:05396b551a9a 89 }
gltest26 9:05396b551a9a 90
tylerjw 11:9a354f34d8e3 91 char ITG3200::getWhoAmI(void)
tylerjw 11:9a354f34d8e3 92 {
gltest26 1:9bef044f45ad 93
gltest26 1:9bef044f45ad 94 //WhoAmI Register address.
gltest26 1:9bef044f45ad 95 char tx = WHO_AM_I_REG;
gltest26 1:9bef044f45ad 96 char rx;
gltest26 1:9bef044f45ad 97
tylerjw 11:9a354f34d8e3 98 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
gltest26 1:9bef044f45ad 99
gltest26 1:9bef044f45ad 100 i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
gltest26 1:9bef044f45ad 101
gltest26 1:9bef044f45ad 102 return rx;
gltest26 1:9bef044f45ad 103
gltest26 1:9bef044f45ad 104 }
gltest26 1:9bef044f45ad 105
tylerjw 11:9a354f34d8e3 106 void ITG3200::setWhoAmI(char address)
tylerjw 11:9a354f34d8e3 107 {
tylerjw 11:9a354f34d8e3 108
tylerjw 11:9a354f34d8e3 109 char tx[2];
tylerjw 11:9a354f34d8e3 110 tx[0] = WHO_AM_I_REG;
tylerjw 11:9a354f34d8e3 111 tx[1] = address;
tylerjw 11:9a354f34d8e3 112
tylerjw 11:9a354f34d8e3 113 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
tylerjw 11:9a354f34d8e3 114
tylerjw 11:9a354f34d8e3 115 }
tylerjw 11:9a354f34d8e3 116
tylerjw 11:9a354f34d8e3 117 char ITG3200::getSampleRateDivider(void)
tylerjw 11:9a354f34d8e3 118 {
tylerjw 11:9a354f34d8e3 119
tylerjw 11:9a354f34d8e3 120 char tx = SMPLRT_DIV_REG;
tylerjw 11:9a354f34d8e3 121 char rx;
tylerjw 11:9a354f34d8e3 122
tylerjw 11:9a354f34d8e3 123 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
tylerjw 11:9a354f34d8e3 124
tylerjw 11:9a354f34d8e3 125 i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
tylerjw 11:9a354f34d8e3 126
tylerjw 11:9a354f34d8e3 127 return rx;
tylerjw 11:9a354f34d8e3 128
tylerjw 11:9a354f34d8e3 129 }
tylerjw 11:9a354f34d8e3 130
tylerjw 11:9a354f34d8e3 131 void ITG3200::setSampleRateDivider(char divider)
tylerjw 11:9a354f34d8e3 132 {
gltest26 1:9bef044f45ad 133
gltest26 1:9bef044f45ad 134 char tx[2];
gltest26 1:9bef044f45ad 135 tx[0] = SMPLRT_DIV_REG;
gltest26 1:9bef044f45ad 136 tx[1] = divider;
gltest26 1:9bef044f45ad 137
gltest26 1:9bef044f45ad 138 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
gltest26 1:9bef044f45ad 139
gltest26 1:9bef044f45ad 140 }
gltest26 1:9bef044f45ad 141
tylerjw 11:9a354f34d8e3 142 int ITG3200::getInternalSampleRate(void)
tylerjw 11:9a354f34d8e3 143 {
gltest26 1:9bef044f45ad 144
gltest26 1:9bef044f45ad 145 char tx = DLPF_FS_REG;
gltest26 1:9bef044f45ad 146 char rx;
tylerjw 11:9a354f34d8e3 147
gltest26 1:9bef044f45ad 148 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
tylerjw 11:9a354f34d8e3 149
gltest26 1:9bef044f45ad 150 i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
tylerjw 11:9a354f34d8e3 151
gltest26 1:9bef044f45ad 152 //DLPF_CFG == 0 -> sample rate = 8kHz.
tylerjw 11:9a354f34d8e3 153 if(rx == 0) {
gltest26 1:9bef044f45ad 154 return 8;
tylerjw 11:9a354f34d8e3 155 }
gltest26 1:9bef044f45ad 156 //DLPF_CFG = 1..7 -> sample rate = 1kHz.
tylerjw 11:9a354f34d8e3 157 else if(rx >= 1 && rx <= 7) {
gltest26 1:9bef044f45ad 158 return 1;
gltest26 1:9bef044f45ad 159 }
gltest26 1:9bef044f45ad 160 //DLPF_CFG = anything else -> something's wrong!
tylerjw 11:9a354f34d8e3 161 else {
gltest26 1:9bef044f45ad 162 return -1;
gltest26 1:9bef044f45ad 163 }
tylerjw 11:9a354f34d8e3 164
gltest26 1:9bef044f45ad 165 }
gltest26 1:9bef044f45ad 166
tylerjw 11:9a354f34d8e3 167 void ITG3200::setLpBandwidth(char bandwidth)
tylerjw 11:9a354f34d8e3 168 {
gltest26 1:9bef044f45ad 169
gltest26 1:9bef044f45ad 170 char tx[2];
gltest26 1:9bef044f45ad 171 tx[0] = DLPF_FS_REG;
gltest26 1:9bef044f45ad 172 //Bits 4,3 are required to be 0x03 for proper operation.
gltest26 1:9bef044f45ad 173 tx[1] = bandwidth | (0x03 << 3);
tylerjw 11:9a354f34d8e3 174
gltest26 1:9bef044f45ad 175 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
gltest26 1:9bef044f45ad 176
gltest26 1:9bef044f45ad 177 }
gltest26 1:9bef044f45ad 178
tylerjw 11:9a354f34d8e3 179 char ITG3200::getInterruptConfiguration(void)
tylerjw 11:9a354f34d8e3 180 {
gltest26 1:9bef044f45ad 181
gltest26 1:9bef044f45ad 182 char tx = INT_CFG_REG;
gltest26 1:9bef044f45ad 183 char rx;
tylerjw 11:9a354f34d8e3 184
gltest26 1:9bef044f45ad 185 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
tylerjw 11:9a354f34d8e3 186
gltest26 1:9bef044f45ad 187 i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
tylerjw 11:9a354f34d8e3 188
gltest26 1:9bef044f45ad 189 return rx;
gltest26 1:9bef044f45ad 190
gltest26 1:9bef044f45ad 191 }
gltest26 1:9bef044f45ad 192
tylerjw 11:9a354f34d8e3 193 void ITG3200::setInterruptConfiguration(char config)
tylerjw 11:9a354f34d8e3 194 {
gltest26 1:9bef044f45ad 195
gltest26 1:9bef044f45ad 196 char tx[2];
gltest26 1:9bef044f45ad 197 tx[0] = INT_CFG_REG;
gltest26 1:9bef044f45ad 198 tx[1] = config;
tylerjw 11:9a354f34d8e3 199
gltest26 1:9bef044f45ad 200 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
gltest26 1:9bef044f45ad 201
gltest26 1:9bef044f45ad 202 }
gltest26 1:9bef044f45ad 203
tylerjw 11:9a354f34d8e3 204 bool ITG3200::isPllReady(void)
tylerjw 11:9a354f34d8e3 205 {
gltest26 1:9bef044f45ad 206
gltest26 1:9bef044f45ad 207 char tx = INT_STATUS;
gltest26 1:9bef044f45ad 208 char rx;
tylerjw 11:9a354f34d8e3 209
gltest26 1:9bef044f45ad 210 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
tylerjw 11:9a354f34d8e3 211
gltest26 1:9bef044f45ad 212 i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
tylerjw 11:9a354f34d8e3 213
gltest26 1:9bef044f45ad 214 //ITG_RDY bit is bit 4 of INT_STATUS register.
tylerjw 11:9a354f34d8e3 215 if(rx & 0x04) {
gltest26 1:9bef044f45ad 216 return true;
tylerjw 11:9a354f34d8e3 217 } else {
gltest26 1:9bef044f45ad 218 return false;
gltest26 1:9bef044f45ad 219 }
tylerjw 11:9a354f34d8e3 220
gltest26 1:9bef044f45ad 221 }
gltest26 1:9bef044f45ad 222
tylerjw 11:9a354f34d8e3 223 bool ITG3200::isRawDataReady(void)
tylerjw 11:9a354f34d8e3 224 {
gltest26 1:9bef044f45ad 225
gltest26 1:9bef044f45ad 226 char tx = INT_STATUS;
gltest26 1:9bef044f45ad 227 char rx;
tylerjw 11:9a354f34d8e3 228
gltest26 1:9bef044f45ad 229 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
tylerjw 11:9a354f34d8e3 230
gltest26 1:9bef044f45ad 231 i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
tylerjw 11:9a354f34d8e3 232
gltest26 1:9bef044f45ad 233 //RAW_DATA_RDY bit is bit 1 of INT_STATUS register.
tylerjw 11:9a354f34d8e3 234 if(rx & 0x01) {
gltest26 1:9bef044f45ad 235 return true;
tylerjw 11:9a354f34d8e3 236 } else {
gltest26 1:9bef044f45ad 237 return false;
gltest26 1:9bef044f45ad 238 }
tylerjw 11:9a354f34d8e3 239
gltest26 1:9bef044f45ad 240 }
gltest26 1:9bef044f45ad 241
tylerjw 11:9a354f34d8e3 242 int ITG3200::getWord(int regi)
tylerjw 11:9a354f34d8e3 243 {
gltest26 1:9bef044f45ad 244
gltest26 4:155c44407af5 245 char tx = regi;
gltest26 1:9bef044f45ad 246 char rx[2];
tylerjw 11:9a354f34d8e3 247
gltest26 2:f44a902ba081 248 i2c_.write(I2C_ADDRESS, &tx, 1);
tylerjw 11:9a354f34d8e3 249
gltest26 2:f44a902ba081 250 i2c_.read(I2C_ADDRESS, rx, 2);
tylerjw 11:9a354f34d8e3 251
gltest26 5:0a0315f0f34e 252 return swapExtend(rx);
gltest26 1:9bef044f45ad 253 }
gltest26 1:9bef044f45ad 254
tylerjw 11:9a354f34d8e3 255 float ITG3200::getTemperature()
tylerjw 11:9a354f34d8e3 256 {
gltest26 1:9bef044f45ad 257 //Offset = -35 degrees, 13200 counts. 280 counts/degrees C.
gltest26 1:9bef044f45ad 258 return 35.0 + ((getRawTemperature() + 13200)/280.0);
tylerjw 11:9a354f34d8e3 259
gltest26 1:9bef044f45ad 260 }
gltest26 1:9bef044f45ad 261
tylerjw 13:e886466d7d67 262 void ITG3200::getRawXYZ(int16_t readings[3])
tylerjw 11:9a354f34d8e3 263 {
gltest26 1:9bef044f45ad 264
gltest26 1:9bef044f45ad 265 char tx = GYRO_XOUT_H_REG;
gltest26 1:9bef044f45ad 266 char rx[2];
tylerjw 11:9a354f34d8e3 267
gltest26 1:9bef044f45ad 268 i2c_.write(I2C_ADDRESS, &tx, 1);
tylerjw 11:9a354f34d8e3 269
gltest26 1:9bef044f45ad 270 i2c_.read(I2C_ADDRESS, rx, 6);
tylerjw 11:9a354f34d8e3 271
gltest26 1:9bef044f45ad 272 for(int i = 0; i < 3; i++)
gltest26 5:0a0315f0f34e 273 readings[i] = swapExtend(&rx[i * 2]);
gltest26 1:9bef044f45ad 274 }
gltest26 1:9bef044f45ad 275
tylerjw 12:d624e9c6dae7 276 void ITG3200::getXYZ(int16_t readings[3], Correction corr)
tylerjw 11:9a354f34d8e3 277 {
tylerjw 12:d624e9c6dae7 278 getRawXYZ(readings);
tylerjw 11:9a354f34d8e3 279 switch(corr) {
tylerjw 11:9a354f34d8e3 280 case OffsetCorrection:
tylerjw 11:9a354f34d8e3 281 for(int i = 0; i < 3; i++)
tylerjw 11:9a354f34d8e3 282 readings[i] -= offset[i];
tylerjw 11:9a354f34d8e3 283 break;
tylerjw 11:9a354f34d8e3 284 case Calibration: {
gltest26 9:05396b551a9a 285 float temp = getTemperature();
gltest26 9:05396b551a9a 286 for(int i = 0; i < 3; i++)
gltest26 9:05396b551a9a 287 readings[i] -= slope[i] * temp + foffset[i];
gltest26 9:05396b551a9a 288 }
gltest26 9:05396b551a9a 289 break;
gltest26 9:05396b551a9a 290 }
gltest26 9:05396b551a9a 291 }
gltest26 9:05396b551a9a 292
gltest26 9:05396b551a9a 293
tylerjw 11:9a354f34d8e3 294 char ITG3200::getPowerManagement(void)
tylerjw 11:9a354f34d8e3 295 {
gltest26 1:9bef044f45ad 296
gltest26 1:9bef044f45ad 297 char tx = PWR_MGM_REG;
gltest26 1:9bef044f45ad 298 char rx;
tylerjw 11:9a354f34d8e3 299
gltest26 1:9bef044f45ad 300 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
tylerjw 11:9a354f34d8e3 301
gltest26 1:9bef044f45ad 302 i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
tylerjw 11:9a354f34d8e3 303
gltest26 1:9bef044f45ad 304 return rx;
gltest26 1:9bef044f45ad 305
gltest26 1:9bef044f45ad 306 }
gltest26 1:9bef044f45ad 307
tylerjw 11:9a354f34d8e3 308 void ITG3200::setPowerManagement(char config)
tylerjw 11:9a354f34d8e3 309 {
gltest26 1:9bef044f45ad 310
gltest26 1:9bef044f45ad 311 char tx[2];
gltest26 1:9bef044f45ad 312 tx[0] = PWR_MGM_REG;
gltest26 1:9bef044f45ad 313 tx[1] = config;
gltest26 1:9bef044f45ad 314
gltest26 1:9bef044f45ad 315 i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
gltest26 1:9bef044f45ad 316
gltest26 1:9bef044f45ad 317 }
gltest26 3:eea9733ca427 318
tylerjw 11:9a354f34d8e3 319 void ITG3200::calibrate(double time)
tylerjw 11:9a354f34d8e3 320 {
gltest26 3:eea9733ca427 321 long sum[3] = {0};
gltest26 3:eea9733ca427 322 int sumCount = 0;
gltest26 6:a7ad6046824c 323 Timer t;
gltest26 6:a7ad6046824c 324 t.start();
tylerjw 11:9a354f34d8e3 325 while(t.read() < time) {
tylerjw 13:e886466d7d67 326 int16_t gyro[3];
tylerjw 12:d624e9c6dae7 327 getRawXYZ(gyro);
gltest26 3:eea9733ca427 328 for(int i = 0; i < 3; i++)
gltest26 3:eea9733ca427 329 sum[i] += gyro[i];
gltest26 3:eea9733ca427 330 sumCount++;
gltest26 3:eea9733ca427 331 }
gltest26 6:a7ad6046824c 332 t.stop();
gltest26 6:a7ad6046824c 333
gltest26 3:eea9733ca427 334 // Avoid zero division
tylerjw 11:9a354f34d8e3 335 if(0 < sumCount) {
gltest26 3:eea9733ca427 336 for(int i = 0; i < 3; i++)
gltest26 3:eea9733ca427 337 offset[i] = sum[i] / sumCount;
gltest26 6:a7ad6046824c 338 // Update member variable only if successful
gltest26 6:a7ad6046824c 339 calibSamples = sumCount;
gltest26 3:eea9733ca427 340 }
gltest26 3:eea9733ca427 341 }