Yifei Teng / MPU9250

MPU9250

Dependents:   FreeIMU

Fork of MPU6050 by Yifei Teng

I2Cdev.cpp@7:95e74f827c08, 2013-11-02 (annotated)

Committer:
tyftyftyf
Date:
Sat Nov 02 17:23:43 2013 +0000
Revision:
7:95e74f827c08
Parent:
1:2daa36bfe56b
Child:
9:d879deb55ae1
Initial Commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
garfieldsg 0:662207e34fba 1 // ported from arduino library: https://github.com/jrowberg/i2cdevlib
garfieldsg 0:662207e34fba 2 // written by szymon gaertig (email: szymon@gaertig.com.pl, website: szymongaertig.pl)
garfieldsg 0:662207e34fba 3 // Changelog:
garfieldsg 0:662207e34fba 4 // 2013-01-08 - first release
garfieldsg 0:662207e34fba 5
garfieldsg 0:662207e34fba 6 #include "I2Cdev.h"
garfieldsg 0:662207e34fba 7
tyftyftyf 7:95e74f827c08 8 //#define useDebugSerial
garfieldsg 0:662207e34fba 9
garfieldsg 0:662207e34fba 10 I2Cdev::I2Cdev(): debugSerial(USBTX, USBRX), i2c(I2C_SDA,I2C_SCL)
garfieldsg 0:662207e34fba 11 {
garfieldsg 0:662207e34fba 12
garfieldsg 0:662207e34fba 13 }
garfieldsg 0:662207e34fba 14
garfieldsg 0:662207e34fba 15 I2Cdev::I2Cdev(PinName i2cSda, PinName i2cScl): debugSerial(USBTX, USBRX), i2c(i2cSda,i2cScl)
garfieldsg 0:662207e34fba 16 {
garfieldsg 0:662207e34fba 17
garfieldsg 0:662207e34fba 18 }
garfieldsg 0:662207e34fba 19
tyftyftyf 7:95e74f827c08 20 I2Cdev::I2Cdev(I2C i2c_): debugSerial(USBTX, USBRX), i2c(i2c_)
tyftyftyf 7:95e74f827c08 21 {
tyftyftyf 7:95e74f827c08 22
tyftyftyf 7:95e74f827c08 23 }
tyftyftyf 7:95e74f827c08 24
garfieldsg 0:662207e34fba 25 /** Read a single bit from an 8-bit device register.
garfieldsg 0:662207e34fba 26 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 27 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 28 * @param bitNum Bit position to read (0-7)
garfieldsg 0:662207e34fba 29 * @param data Container for single bit value
garfieldsg 0:662207e34fba 30 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 31 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 32 */
garfieldsg 0:662207e34fba 33 int8_t I2Cdev::readBit(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint8_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 34 uint8_t b;
garfieldsg 0:662207e34fba 35 uint8_t count = readByte(devAddr, regAddr, &b, timeout);
garfieldsg 0:662207e34fba 36 *data = b & (1 << bitNum);
garfieldsg 0:662207e34fba 37 return count;
garfieldsg 0:662207e34fba 38 }
garfieldsg 0:662207e34fba 39
garfieldsg 0:662207e34fba 40 /** Read a single bit from a 16-bit device register.
garfieldsg 0:662207e34fba 41 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 42 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 43 * @param bitNum Bit position to read (0-15)
garfieldsg 0:662207e34fba 44 * @param data Container for single bit value
garfieldsg 0:662207e34fba 45 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 46 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 47 */
garfieldsg 0:662207e34fba 48 int8_t I2Cdev::readBitW(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint16_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 49 uint16_t b;
garfieldsg 0:662207e34fba 50 uint8_t count = readWord(devAddr, regAddr, &b, timeout);
garfieldsg 0:662207e34fba 51 *data = b & (1 << bitNum);
garfieldsg 0:662207e34fba 52 return count;
garfieldsg 0:662207e34fba 53 }
garfieldsg 0:662207e34fba 54
garfieldsg 0:662207e34fba 55 /** Read multiple bits from an 8-bit device register.
garfieldsg 0:662207e34fba 56 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 57 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 58 * @param bitStart First bit position to read (0-7)
garfieldsg 0:662207e34fba 59 * @param length Number of bits to read (not more than 8)
garfieldsg 0:662207e34fba 60 * @param data Container for right-aligned value (i.e. '101' read from any bitStart position will equal 0x05)
garfieldsg 0:662207e34fba 61 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 62 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 63 */
garfieldsg 0:662207e34fba 64 int8_t I2Cdev::readBits(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint8_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 65 // 01101001 read byte
garfieldsg 0:662207e34fba 66 // 76543210 bit numbers
garfieldsg 0:662207e34fba 67 // xxx args: bitStart=4, length=3
garfieldsg 0:662207e34fba 68 // 010 masked
garfieldsg 0:662207e34fba 69 // -> 010 shifted
garfieldsg 0:662207e34fba 70 uint8_t count, b;
garfieldsg 0:662207e34fba 71 if ((count = readByte(devAddr, regAddr, &b, timeout)) != 0) {
garfieldsg 0:662207e34fba 72 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
garfieldsg 0:662207e34fba 73 b &= mask;
garfieldsg 0:662207e34fba 74 b >>= (bitStart - length + 1);
garfieldsg 0:662207e34fba 75 *data = b;
garfieldsg 0:662207e34fba 76 }
garfieldsg 0:662207e34fba 77 return count;
garfieldsg 0:662207e34fba 78 }
garfieldsg 0:662207e34fba 79
garfieldsg 0:662207e34fba 80 /** Read multiple bits from a 16-bit device register.
garfieldsg 0:662207e34fba 81 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 82 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 83 * @param bitStart First bit position to read (0-15)
garfieldsg 0:662207e34fba 84 * @param length Number of bits to read (not more than 16)
garfieldsg 0:662207e34fba 85 * @param data Container for right-aligned value (i.e. '101' read from any bitStart position will equal 0x05)
garfieldsg 0:662207e34fba 86 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 87 * @return Status of read operation (1 = success, 0 = failure, -1 = timeout)
garfieldsg 0:662207e34fba 88 */
garfieldsg 0:662207e34fba 89 int8_t I2Cdev::readBitsW(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint16_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 90 // 1101011001101001 read byte
garfieldsg 0:662207e34fba 91 // fedcba9876543210 bit numbers
garfieldsg 0:662207e34fba 92 // xxx args: bitStart=12, length=3
garfieldsg 0:662207e34fba 93 // 010 masked
garfieldsg 0:662207e34fba 94 // -> 010 shifted
garfieldsg 0:662207e34fba 95 uint8_t count;
garfieldsg 0:662207e34fba 96 uint16_t w;
garfieldsg 0:662207e34fba 97 if ((count = readWord(devAddr, regAddr, &w, timeout)) != 0) {
garfieldsg 0:662207e34fba 98 uint16_t mask = ((1 << length) - 1) << (bitStart - length + 1);
garfieldsg 0:662207e34fba 99 w &= mask;
garfieldsg 0:662207e34fba 100 w >>= (bitStart - length + 1);
garfieldsg 0:662207e34fba 101 *data = w;
garfieldsg 0:662207e34fba 102 }
garfieldsg 0:662207e34fba 103 return count;
garfieldsg 0:662207e34fba 104 }
garfieldsg 0:662207e34fba 105 /** Read single byte from an 8-bit device register.
garfieldsg 0:662207e34fba 106 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 107 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 108 * @param data Container for byte value read from device
garfieldsg 0:662207e34fba 109 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 110 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 111 */
garfieldsg 0:662207e34fba 112 int8_t I2Cdev::readByte(uint8_t devAddr, uint8_t regAddr, uint8_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 113 return readBytes(devAddr, regAddr, 1, data, timeout);
garfieldsg 0:662207e34fba 114 }
garfieldsg 0:662207e34fba 115
garfieldsg 0:662207e34fba 116 /** Read single word from a 16-bit device register.
garfieldsg 0:662207e34fba 117 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 118 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 119 * @param data Container for word value read from device
garfieldsg 0:662207e34fba 120 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 121 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 122 */
garfieldsg 0:662207e34fba 123 int8_t I2Cdev::readWord(uint8_t devAddr, uint8_t regAddr, uint16_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 124 return readWords(devAddr, regAddr, 1, data, timeout);
garfieldsg 0:662207e34fba 125 }
garfieldsg 0:662207e34fba 126
garfieldsg 0:662207e34fba 127 /** Read multiple bytes from an 8-bit device register.
garfieldsg 0:662207e34fba 128 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 129 * @param regAddr First register regAddr to read from
garfieldsg 0:662207e34fba 130 * @param length Number of bytes to read
garfieldsg 0:662207e34fba 131 * @param data Buffer to store read data in
garfieldsg 0:662207e34fba 132 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 133 * @return Number of bytes read (-1 indicates failure)
garfieldsg 0:662207e34fba 134 */
garfieldsg 0:662207e34fba 135 int8_t I2Cdev::readBytes(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint8_t *data, uint16_t timeout)
garfieldsg 0:662207e34fba 136 {
garfieldsg 0:662207e34fba 137 char command[1];
garfieldsg 0:662207e34fba 138 command[0] = regAddr;
garfieldsg 0:662207e34fba 139 char *redData = (char*)malloc(length);
garfieldsg 0:662207e34fba 140 i2c.write(devAddr<<1, command, 1, true);
tyftyftyf 7:95e74f827c08 141 i2c.read((devAddr<<1)+1, redData, length);
garfieldsg 0:662207e34fba 142 for(int i =0; i < length; i++) {
garfieldsg 0:662207e34fba 143 data[i] = redData[i];
garfieldsg 0:662207e34fba 144 }
pommzorz 1:2daa36bfe56b 145 free(redData);
garfieldsg 0:662207e34fba 146 return length;
garfieldsg 0:662207e34fba 147 }
garfieldsg 0:662207e34fba 148
garfieldsg 0:662207e34fba 149 int8_t I2Cdev::readWords(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint16_t *data, uint16_t timeout)
garfieldsg 0:662207e34fba 150 {
garfieldsg 0:662207e34fba 151 return 0;
garfieldsg 0:662207e34fba 152 }
garfieldsg 0:662207e34fba 153
garfieldsg 0:662207e34fba 154 /** write a single bit in an 8-bit device register.
garfieldsg 0:662207e34fba 155 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 156 * @param regAddr Register regAddr to write to
garfieldsg 0:662207e34fba 157 * @param bitNum Bit position to write (0-7)
garfieldsg 0:662207e34fba 158 * @param value New bit value to write
garfieldsg 0:662207e34fba 159 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 160 */
garfieldsg 0:662207e34fba 161 bool I2Cdev::writeBit(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint8_t data) {
garfieldsg 0:662207e34fba 162 uint8_t b;
garfieldsg 0:662207e34fba 163 readByte(devAddr, regAddr, &b);
garfieldsg 0:662207e34fba 164 b = (data != 0) ? (b | (1 << bitNum)) : (b & ~(1 << bitNum));
garfieldsg 0:662207e34fba 165 return writeByte(devAddr, regAddr, b);
garfieldsg 0:662207e34fba 166 }
garfieldsg 0:662207e34fba 167
garfieldsg 0:662207e34fba 168 /** write a single bit in a 16-bit device register.
garfieldsg 0:662207e34fba 169 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 170 * @param regAddr Register regAddr to write to
garfieldsg 0:662207e34fba 171 * @param bitNum Bit position to write (0-15)
garfieldsg 0:662207e34fba 172 * @param value New bit value to write
garfieldsg 0:662207e34fba 173 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 174 */
garfieldsg 0:662207e34fba 175 bool I2Cdev::writeBitW(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint16_t data) {
garfieldsg 0:662207e34fba 176 uint16_t w;
garfieldsg 0:662207e34fba 177 readWord(devAddr, regAddr, &w);
garfieldsg 0:662207e34fba 178 w = (data != 0) ? (w | (1 << bitNum)) : (w & ~(1 << bitNum));
garfieldsg 0:662207e34fba 179 return writeWord(devAddr, regAddr, w);
garfieldsg 0:662207e34fba 180 }
garfieldsg 0:662207e34fba 181
garfieldsg 0:662207e34fba 182 /** Write multiple bits in an 8-bit device register.
garfieldsg 0:662207e34fba 183 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 184 * @param regAddr Register regAddr to write to
garfieldsg 0:662207e34fba 185 * @param bitStart First bit position to write (0-7)
garfieldsg 0:662207e34fba 186 * @param length Number of bits to write (not more than 8)
garfieldsg 0:662207e34fba 187 * @param data Right-aligned value to write
garfieldsg 0:662207e34fba 188 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 189 */
garfieldsg 0:662207e34fba 190 bool I2Cdev::writeBits(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint8_t data) {
garfieldsg 0:662207e34fba 191 // 010 value to write
garfieldsg 0:662207e34fba 192 // 76543210 bit numbers
garfieldsg 0:662207e34fba 193 // xxx args: bitStart=4, length=3
garfieldsg 0:662207e34fba 194 // 00011100 mask byte
garfieldsg 0:662207e34fba 195 // 10101111 original value (sample)
garfieldsg 0:662207e34fba 196 // 10100011 original & ~mask
garfieldsg 0:662207e34fba 197 // 10101011 masked | value
garfieldsg 0:662207e34fba 198 uint8_t b;
garfieldsg 0:662207e34fba 199 if (readByte(devAddr, regAddr, &b) != 0) {
garfieldsg 0:662207e34fba 200 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
garfieldsg 0:662207e34fba 201 data <<= (bitStart - length + 1); // shift data into correct position
garfieldsg 0:662207e34fba 202 data &= mask; // zero all non-important bits in data
garfieldsg 0:662207e34fba 203 b &= ~(mask); // zero all important bits in existing byte
garfieldsg 0:662207e34fba 204 b |= data; // combine data with existing byte
garfieldsg 0:662207e34fba 205 return writeByte(devAddr, regAddr, b);
garfieldsg 0:662207e34fba 206 } else {
garfieldsg 0:662207e34fba 207 return false;
garfieldsg 0:662207e34fba 208 }
garfieldsg 0:662207e34fba 209 }
garfieldsg 0:662207e34fba 210
garfieldsg 0:662207e34fba 211 /** Write multiple bits in a 16-bit device register.
garfieldsg 0:662207e34fba 212 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 213 * @param regAddr Register regAddr to write to
garfieldsg 0:662207e34fba 214 * @param bitStart First bit position to write (0-15)
garfieldsg 0:662207e34fba 215 * @param length Number of bits to write (not more than 16)
garfieldsg 0:662207e34fba 216 * @param data Right-aligned value to write
garfieldsg 0:662207e34fba 217 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 218 */
garfieldsg 0:662207e34fba 219 bool I2Cdev::writeBitsW(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint16_t data) {
garfieldsg 0:662207e34fba 220 // 010 value to write
garfieldsg 0:662207e34fba 221 // fedcba9876543210 bit numbers
garfieldsg 0:662207e34fba 222 // xxx args: bitStart=12, length=3
garfieldsg 0:662207e34fba 223 // 0001110000000000 mask byte
garfieldsg 0:662207e34fba 224 // 1010111110010110 original value (sample)
garfieldsg 0:662207e34fba 225 // 1010001110010110 original & ~mask
garfieldsg 0:662207e34fba 226 // 1010101110010110 masked | value
garfieldsg 0:662207e34fba 227 uint16_t w;
garfieldsg 0:662207e34fba 228 if (readWord(devAddr, regAddr, &w) != 0) {
garfieldsg 0:662207e34fba 229 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
garfieldsg 0:662207e34fba 230 data <<= (bitStart - length + 1); // shift data into correct position
garfieldsg 0:662207e34fba 231 data &= mask; // zero all non-important bits in data
garfieldsg 0:662207e34fba 232 w &= ~(mask); // zero all important bits in existing word
garfieldsg 0:662207e34fba 233 w |= data; // combine data with existing word
garfieldsg 0:662207e34fba 234 return writeWord(devAddr, regAddr, w);
garfieldsg 0:662207e34fba 235 } else {
garfieldsg 0:662207e34fba 236 return false;
garfieldsg 0:662207e34fba 237 }
garfieldsg 0:662207e34fba 238 }
garfieldsg 0:662207e34fba 239
garfieldsg 0:662207e34fba 240 /** Write single byte to an 8-bit device register.
garfieldsg 0:662207e34fba 241 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 242 * @param regAddr Register address to write to
garfieldsg 0:662207e34fba 243 * @param data New byte value to write
garfieldsg 0:662207e34fba 244 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 245 */
garfieldsg 0:662207e34fba 246 bool I2Cdev::writeByte(uint8_t devAddr, uint8_t regAddr, uint8_t data) {
garfieldsg 0:662207e34fba 247 return writeBytes(devAddr, regAddr, 1, &data);
garfieldsg 0:662207e34fba 248 }
garfieldsg 0:662207e34fba 249
garfieldsg 0:662207e34fba 250 /** Write single word to a 16-bit device register.
garfieldsg 0:662207e34fba 251 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 252 * @param regAddr Register address to write to
garfieldsg 0:662207e34fba 253 * @param data New word value to write
garfieldsg 0:662207e34fba 254 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 255 */
garfieldsg 0:662207e34fba 256 bool I2Cdev::writeWord(uint8_t devAddr, uint8_t regAddr, uint16_t data) {
garfieldsg 0:662207e34fba 257 return writeWords(devAddr, regAddr, 1, &data);
garfieldsg 0:662207e34fba 258 }
garfieldsg 0:662207e34fba 259
garfieldsg 0:662207e34fba 260 bool I2Cdev::writeBytes(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint8_t *data)
garfieldsg 0:662207e34fba 261 {
garfieldsg 0:662207e34fba 262 i2c.start();
garfieldsg 0:662207e34fba 263 i2c.write(devAddr<<1);
garfieldsg 0:662207e34fba 264 i2c.write(regAddr);
garfieldsg 0:662207e34fba 265 for(int i = 0; i < length; i++) {
garfieldsg 0:662207e34fba 266 i2c.write(data[i]);
garfieldsg 0:662207e34fba 267 }
garfieldsg 0:662207e34fba 268 i2c.stop();
garfieldsg 0:662207e34fba 269 return true;
garfieldsg 0:662207e34fba 270 }
garfieldsg 0:662207e34fba 271
garfieldsg 0:662207e34fba 272 bool I2Cdev::writeWords(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint16_t *data)
garfieldsg 0:662207e34fba 273 {
garfieldsg 0:662207e34fba 274 return true;
garfieldsg 0:662207e34fba 275 }
garfieldsg 0:662207e34fba 276
garfieldsg 0:662207e34fba 277 uint16_t I2Cdev::readTimeout(void)
garfieldsg 0:662207e34fba 278 {
garfieldsg 0:662207e34fba 279 return 0;
garfieldsg 0:662207e34fba 280 }