yan zhang / MPU9150

mpu9150

Fork of MPU9150 by Shundo Kishi

I2Cdev.cpp@3:16a08969e192, 2017-06-21 (annotated)

Committer:
donghuoyinzi
Date:
Wed Jun 21 05:06:51 2017 +0000
Revision:
3:16a08969e192
new fusion

Who changed what in which revision?

UserRevisionLine numberNew contents of line
donghuoyinzi 3:16a08969e192 1 // ported from arduino library: https://github.com/jrowberg/i2cdevlib
donghuoyinzi 3:16a08969e192 2 // written by szymon gaertig (email: szymon@gaertig.com.pl, website: szymongaertig.pl)
donghuoyinzi 3:16a08969e192 3 // modified by shundo kishi
donghuoyinzi 3:16a08969e192 4 //
donghuoyinzi 3:16a08969e192 5 // Changelog:
donghuoyinzi 3:16a08969e192 6 // 2013-01-08 - first release
donghuoyinzi 3:16a08969e192 7 // 2016-01-31 - changed all functions and variables static to make porting from arduino easier(by shundo kishi)
donghuoyinzi 3:16a08969e192 8
donghuoyinzi 3:16a08969e192 9 #include "I2Cdev.h"
donghuoyinzi 3:16a08969e192 10
donghuoyinzi 3:16a08969e192 11 I2C I2Cdev::i2c(I2C_SDA,I2C_SCL);
donghuoyinzi 3:16a08969e192 12
donghuoyinzi 3:16a08969e192 13 /** Default constructor.
donghuoyinzi 3:16a08969e192 14 */
donghuoyinzi 3:16a08969e192 15 I2Cdev::I2Cdev() {
donghuoyinzi 3:16a08969e192 16 }
donghuoyinzi 3:16a08969e192 17
donghuoyinzi 3:16a08969e192 18 /** Read a single bit from an 8-bit device register.
donghuoyinzi 3:16a08969e192 19 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 20 * @param regAddr Register regAddr to read from
donghuoyinzi 3:16a08969e192 21 * @param bitNum Bit position to read (0-7)
donghuoyinzi 3:16a08969e192 22 * @param data Container for single bit value
donghuoyinzi 3:16a08969e192 23 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
donghuoyinzi 3:16a08969e192 24 * @return Status of read operation (true = success)
donghuoyinzi 3:16a08969e192 25 */
donghuoyinzi 3:16a08969e192 26 int8_t I2Cdev::readBit(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint8_t *data, uint16_t timeout) {
donghuoyinzi 3:16a08969e192 27 uint8_t b;
donghuoyinzi 3:16a08969e192 28 uint8_t count = readByte(devAddr, regAddr, &b, timeout);
donghuoyinzi 3:16a08969e192 29 *data = b & (1 << bitNum);
donghuoyinzi 3:16a08969e192 30 return count;
donghuoyinzi 3:16a08969e192 31 }
donghuoyinzi 3:16a08969e192 32
donghuoyinzi 3:16a08969e192 33 /** Read a single bit from a 16-bit device register.
donghuoyinzi 3:16a08969e192 34 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 35 * @param regAddr Register regAddr to read from
donghuoyinzi 3:16a08969e192 36 * @param bitNum Bit position to read (0-15)
donghuoyinzi 3:16a08969e192 37 * @param data Container for single bit value
donghuoyinzi 3:16a08969e192 38 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
donghuoyinzi 3:16a08969e192 39 * @return Status of read operation (true = success)
donghuoyinzi 3:16a08969e192 40 */
donghuoyinzi 3:16a08969e192 41 int8_t I2Cdev::readBitW(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint16_t *data, uint16_t timeout) {
donghuoyinzi 3:16a08969e192 42 uint16_t b;
donghuoyinzi 3:16a08969e192 43 uint8_t count = readWord(devAddr, regAddr, &b, timeout);
donghuoyinzi 3:16a08969e192 44 *data = b & (1 << bitNum);
donghuoyinzi 3:16a08969e192 45 return count;
donghuoyinzi 3:16a08969e192 46 }
donghuoyinzi 3:16a08969e192 47
donghuoyinzi 3:16a08969e192 48 /** Read multiple bits from an 8-bit device register.
donghuoyinzi 3:16a08969e192 49 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 50 * @param regAddr Register regAddr to read from
donghuoyinzi 3:16a08969e192 51 * @param bitStart First bit position to read (0-7)
donghuoyinzi 3:16a08969e192 52 * @param length Number of bits to read (not more than 8)
donghuoyinzi 3:16a08969e192 53 * @param data Container for right-aligned value (i.e. '101' read from any bitStart position will equal 0x05)
donghuoyinzi 3:16a08969e192 54 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
donghuoyinzi 3:16a08969e192 55 * @return Status of read operation (true = success)
donghuoyinzi 3:16a08969e192 56 */
donghuoyinzi 3:16a08969e192 57 int8_t I2Cdev::readBits(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint8_t *data, uint16_t timeout) {
donghuoyinzi 3:16a08969e192 58 // 01101001 read byte
donghuoyinzi 3:16a08969e192 59 // 76543210 bit numbers
donghuoyinzi 3:16a08969e192 60 // xxx args: bitStart=4, length=3
donghuoyinzi 3:16a08969e192 61 // 010 masked
donghuoyinzi 3:16a08969e192 62 // -> 010 shifted
donghuoyinzi 3:16a08969e192 63 uint8_t count, b;
donghuoyinzi 3:16a08969e192 64 if ((count = readByte(devAddr, regAddr, &b, timeout)) != 0) {
donghuoyinzi 3:16a08969e192 65 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
donghuoyinzi 3:16a08969e192 66 b &= mask;
donghuoyinzi 3:16a08969e192 67 b >>= (bitStart - length + 1);
donghuoyinzi 3:16a08969e192 68 *data = b;
donghuoyinzi 3:16a08969e192 69 }
donghuoyinzi 3:16a08969e192 70 return count;
donghuoyinzi 3:16a08969e192 71 }
donghuoyinzi 3:16a08969e192 72
donghuoyinzi 3:16a08969e192 73 /** Read multiple bits from a 16-bit device register.
donghuoyinzi 3:16a08969e192 74 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 75 * @param regAddr Register regAddr to read from
donghuoyinzi 3:16a08969e192 76 * @param bitStart First bit position to read (0-15)
donghuoyinzi 3:16a08969e192 77 * @param length Number of bits to read (not more than 16)
donghuoyinzi 3:16a08969e192 78 * @param data Container for right-aligned value (i.e. '101' read from any bitStart position will equal 0x05)
donghuoyinzi 3:16a08969e192 79 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
donghuoyinzi 3:16a08969e192 80 * @return Status of read operation (1 = success, 0 = failure, -1 = timeout)
donghuoyinzi 3:16a08969e192 81 */
donghuoyinzi 3:16a08969e192 82 int8_t I2Cdev::readBitsW(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint16_t *data, uint16_t timeout) {
donghuoyinzi 3:16a08969e192 83 // 1101011001101001 read byte
donghuoyinzi 3:16a08969e192 84 // fedcba9876543210 bit numbers
donghuoyinzi 3:16a08969e192 85 // xxx args: bitStart=12, length=3
donghuoyinzi 3:16a08969e192 86 // 010 masked
donghuoyinzi 3:16a08969e192 87 // -> 010 shifted
donghuoyinzi 3:16a08969e192 88 uint8_t count;
donghuoyinzi 3:16a08969e192 89 uint16_t w;
donghuoyinzi 3:16a08969e192 90 if ((count = readWord(devAddr, regAddr, &w, timeout)) != 0) {
donghuoyinzi 3:16a08969e192 91 uint16_t mask = ((1 << length) - 1) << (bitStart - length + 1);
donghuoyinzi 3:16a08969e192 92 w &= mask;
donghuoyinzi 3:16a08969e192 93 w >>= (bitStart - length + 1);
donghuoyinzi 3:16a08969e192 94 *data = w;
donghuoyinzi 3:16a08969e192 95 }
donghuoyinzi 3:16a08969e192 96 return count;
donghuoyinzi 3:16a08969e192 97 }
donghuoyinzi 3:16a08969e192 98 /** Read single byte from an 8-bit device register.
donghuoyinzi 3:16a08969e192 99 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 100 * @param regAddr Register regAddr to read from
donghuoyinzi 3:16a08969e192 101 * @param data Container for byte value read from device
donghuoyinzi 3:16a08969e192 102 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
donghuoyinzi 3:16a08969e192 103 * @return Status of read operation (true = success)
donghuoyinzi 3:16a08969e192 104 */
donghuoyinzi 3:16a08969e192 105 int8_t I2Cdev::readByte(uint8_t devAddr, uint8_t regAddr, uint8_t *data, uint16_t timeout) {
donghuoyinzi 3:16a08969e192 106 return readBytes(devAddr, regAddr, 1, data, timeout);
donghuoyinzi 3:16a08969e192 107 }
donghuoyinzi 3:16a08969e192 108
donghuoyinzi 3:16a08969e192 109 /** Read single word from a 16-bit device register.
donghuoyinzi 3:16a08969e192 110 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 111 * @param regAddr Register regAddr to read from
donghuoyinzi 3:16a08969e192 112 * @param data Container for word value read from device
donghuoyinzi 3:16a08969e192 113 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
donghuoyinzi 3:16a08969e192 114 * @return Status of read operation (true = success)
donghuoyinzi 3:16a08969e192 115 */
donghuoyinzi 3:16a08969e192 116 int8_t I2Cdev::readWord(uint8_t devAddr, uint8_t regAddr, uint16_t *data, uint16_t timeout) {
donghuoyinzi 3:16a08969e192 117 return readWords(devAddr, regAddr, 1, data, timeout);
donghuoyinzi 3:16a08969e192 118 }
donghuoyinzi 3:16a08969e192 119
donghuoyinzi 3:16a08969e192 120 /** Read multiple bytes from an 8-bit device register.
donghuoyinzi 3:16a08969e192 121 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 122 * @param regAddr First register regAddr to read from
donghuoyinzi 3:16a08969e192 123 * @param length Number of bytes to read
donghuoyinzi 3:16a08969e192 124 * @param data Buffer to store read data in
donghuoyinzi 3:16a08969e192 125 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
donghuoyinzi 3:16a08969e192 126 * @return Number of bytes read (-1 indicates failure)
donghuoyinzi 3:16a08969e192 127 */
donghuoyinzi 3:16a08969e192 128 int8_t I2Cdev::readBytes(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint8_t *data, uint16_t timeout)
donghuoyinzi 3:16a08969e192 129 {
donghuoyinzi 3:16a08969e192 130 char command[1];
donghuoyinzi 3:16a08969e192 131 command[0] = regAddr;
donghuoyinzi 3:16a08969e192 132 char *redData = (char*)malloc(length);
donghuoyinzi 3:16a08969e192 133 i2c.write(devAddr<<1, command, 1, true);
donghuoyinzi 3:16a08969e192 134 i2c.read(devAddr<<1, redData, length);
donghuoyinzi 3:16a08969e192 135 for(int i =0; i < length; i++) {
donghuoyinzi 3:16a08969e192 136 data[i] = redData[i];
donghuoyinzi 3:16a08969e192 137 }
donghuoyinzi 3:16a08969e192 138 free (redData);
donghuoyinzi 3:16a08969e192 139 return length;
donghuoyinzi 3:16a08969e192 140 }
donghuoyinzi 3:16a08969e192 141
donghuoyinzi 3:16a08969e192 142 int8_t I2Cdev::readWords(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint16_t *data, uint16_t timeout)
donghuoyinzi 3:16a08969e192 143 {
donghuoyinzi 3:16a08969e192 144 return 0;
donghuoyinzi 3:16a08969e192 145 }
donghuoyinzi 3:16a08969e192 146
donghuoyinzi 3:16a08969e192 147 /** write a single bit in an 8-bit device register.
donghuoyinzi 3:16a08969e192 148 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 149 * @param regAddr Register regAddr to write to
donghuoyinzi 3:16a08969e192 150 * @param bitNum Bit position to write (0-7)
donghuoyinzi 3:16a08969e192 151 * @param value New bit value to write
donghuoyinzi 3:16a08969e192 152 * @return Status of operation (true = success)
donghuoyinzi 3:16a08969e192 153 */
donghuoyinzi 3:16a08969e192 154 bool I2Cdev::writeBit(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint8_t data) {
donghuoyinzi 3:16a08969e192 155 uint8_t b;
donghuoyinzi 3:16a08969e192 156 readByte(devAddr, regAddr, &b);
donghuoyinzi 3:16a08969e192 157 b = (data != 0) ? (b | (1 << bitNum)) : (b & ~(1 << bitNum));
donghuoyinzi 3:16a08969e192 158 return writeByte(devAddr, regAddr, b);
donghuoyinzi 3:16a08969e192 159 }
donghuoyinzi 3:16a08969e192 160
donghuoyinzi 3:16a08969e192 161 /** write a single bit in a 16-bit device register.
donghuoyinzi 3:16a08969e192 162 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 163 * @param regAddr Register regAddr to write to
donghuoyinzi 3:16a08969e192 164 * @param bitNum Bit position to write (0-15)
donghuoyinzi 3:16a08969e192 165 * @param value New bit value to write
donghuoyinzi 3:16a08969e192 166 * @return Status of operation (true = success)
donghuoyinzi 3:16a08969e192 167 */
donghuoyinzi 3:16a08969e192 168 bool I2Cdev::writeBitW(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint16_t data) {
donghuoyinzi 3:16a08969e192 169 uint16_t w;
donghuoyinzi 3:16a08969e192 170 readWord(devAddr, regAddr, &w);
donghuoyinzi 3:16a08969e192 171 w = (data != 0) ? (w | (1 << bitNum)) : (w & ~(1 << bitNum));
donghuoyinzi 3:16a08969e192 172 return writeWord(devAddr, regAddr, w);
donghuoyinzi 3:16a08969e192 173 }
donghuoyinzi 3:16a08969e192 174
donghuoyinzi 3:16a08969e192 175 /** Write multiple bits in an 8-bit device register.
donghuoyinzi 3:16a08969e192 176 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 177 * @param regAddr Register regAddr to write to
donghuoyinzi 3:16a08969e192 178 * @param bitStart First bit position to write (0-7)
donghuoyinzi 3:16a08969e192 179 * @param length Number of bits to write (not more than 8)
donghuoyinzi 3:16a08969e192 180 * @param data Right-aligned value to write
donghuoyinzi 3:16a08969e192 181 * @return Status of operation (true = success)
donghuoyinzi 3:16a08969e192 182 */
donghuoyinzi 3:16a08969e192 183 bool I2Cdev::writeBits(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint8_t data) {
donghuoyinzi 3:16a08969e192 184 // 010 value to write
donghuoyinzi 3:16a08969e192 185 // 76543210 bit numbers
donghuoyinzi 3:16a08969e192 186 // xxx args: bitStart=4, length=3
donghuoyinzi 3:16a08969e192 187 // 00011100 mask byte
donghuoyinzi 3:16a08969e192 188 // 10101111 original value (sample)
donghuoyinzi 3:16a08969e192 189 // 10100011 original & ~mask
donghuoyinzi 3:16a08969e192 190 // 10101011 masked | value
donghuoyinzi 3:16a08969e192 191 uint8_t b;
donghuoyinzi 3:16a08969e192 192 if (readByte(devAddr, regAddr, &b) != 0) {
donghuoyinzi 3:16a08969e192 193 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
donghuoyinzi 3:16a08969e192 194 data <<= (bitStart - length + 1); // shift data into correct position
donghuoyinzi 3:16a08969e192 195 data &= mask; // zero all non-important bits in data
donghuoyinzi 3:16a08969e192 196 b &= ~(mask); // zero all important bits in existing byte
donghuoyinzi 3:16a08969e192 197 b |= data; // combine data with existing byte
donghuoyinzi 3:16a08969e192 198 return writeByte(devAddr, regAddr, b);
donghuoyinzi 3:16a08969e192 199 } else {
donghuoyinzi 3:16a08969e192 200 return false;
donghuoyinzi 3:16a08969e192 201 }
donghuoyinzi 3:16a08969e192 202 }
donghuoyinzi 3:16a08969e192 203
donghuoyinzi 3:16a08969e192 204 /** Write multiple bits in a 16-bit device register.
donghuoyinzi 3:16a08969e192 205 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 206 * @param regAddr Register regAddr to write to
donghuoyinzi 3:16a08969e192 207 * @param bitStart First bit position to write (0-15)
donghuoyinzi 3:16a08969e192 208 * @param length Number of bits to write (not more than 16)
donghuoyinzi 3:16a08969e192 209 * @param data Right-aligned value to write
donghuoyinzi 3:16a08969e192 210 * @return Status of operation (true = success)
donghuoyinzi 3:16a08969e192 211 */
donghuoyinzi 3:16a08969e192 212 bool I2Cdev::writeBitsW(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint16_t data) {
donghuoyinzi 3:16a08969e192 213 // 010 value to write
donghuoyinzi 3:16a08969e192 214 // fedcba9876543210 bit numbers
donghuoyinzi 3:16a08969e192 215 // xxx args: bitStart=12, length=3
donghuoyinzi 3:16a08969e192 216 // 0001110000000000 mask byte
donghuoyinzi 3:16a08969e192 217 // 1010111110010110 original value (sample)
donghuoyinzi 3:16a08969e192 218 // 1010001110010110 original & ~mask
donghuoyinzi 3:16a08969e192 219 // 1010101110010110 masked | value
donghuoyinzi 3:16a08969e192 220 uint16_t w;
donghuoyinzi 3:16a08969e192 221 if (readWord(devAddr, regAddr, &w) != 0) {
donghuoyinzi 3:16a08969e192 222 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
donghuoyinzi 3:16a08969e192 223 data <<= (bitStart - length + 1); // shift data into correct position
donghuoyinzi 3:16a08969e192 224 data &= mask; // zero all non-important bits in data
donghuoyinzi 3:16a08969e192 225 w &= ~(mask); // zero all important bits in existing word
donghuoyinzi 3:16a08969e192 226 w |= data; // combine data with existing word
donghuoyinzi 3:16a08969e192 227 return writeWord(devAddr, regAddr, w);
donghuoyinzi 3:16a08969e192 228 } else {
donghuoyinzi 3:16a08969e192 229 return false;
donghuoyinzi 3:16a08969e192 230 }
donghuoyinzi 3:16a08969e192 231 }
donghuoyinzi 3:16a08969e192 232
donghuoyinzi 3:16a08969e192 233 /** Write single byte to an 8-bit device register.
donghuoyinzi 3:16a08969e192 234 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 235 * @param regAddr Register address to write to
donghuoyinzi 3:16a08969e192 236 * @param data New byte value to write
donghuoyinzi 3:16a08969e192 237 * @return Status of operation (true = success)
donghuoyinzi 3:16a08969e192 238 */
donghuoyinzi 3:16a08969e192 239 bool I2Cdev::writeByte(uint8_t devAddr, uint8_t regAddr, uint8_t data) {
donghuoyinzi 3:16a08969e192 240 return writeBytes(devAddr, regAddr, 1, &data);
donghuoyinzi 3:16a08969e192 241 }
donghuoyinzi 3:16a08969e192 242
donghuoyinzi 3:16a08969e192 243 /** Write single word to a 16-bit device register.
donghuoyinzi 3:16a08969e192 244 * @param devAddr I2C slave device address
donghuoyinzi 3:16a08969e192 245 * @param regAddr Register address to write to
donghuoyinzi 3:16a08969e192 246 * @param data New word value to write
donghuoyinzi 3:16a08969e192 247 * @return Status of operation (true = success)
donghuoyinzi 3:16a08969e192 248 */
donghuoyinzi 3:16a08969e192 249 bool I2Cdev::writeWord(uint8_t devAddr, uint8_t regAddr, uint16_t data) {
donghuoyinzi 3:16a08969e192 250 return writeWords(devAddr, regAddr, 1, &data);
donghuoyinzi 3:16a08969e192 251 }
donghuoyinzi 3:16a08969e192 252
donghuoyinzi 3:16a08969e192 253 bool I2Cdev::writeBytes(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint8_t *data)
donghuoyinzi 3:16a08969e192 254 {
donghuoyinzi 3:16a08969e192 255 i2c.start();
donghuoyinzi 3:16a08969e192 256 i2c.write(devAddr<<1);
donghuoyinzi 3:16a08969e192 257 i2c.write(regAddr);
donghuoyinzi 3:16a08969e192 258 for(int i = 0; i < length; i++) {
donghuoyinzi 3:16a08969e192 259 i2c.write(data[i]);
donghuoyinzi 3:16a08969e192 260 }
donghuoyinzi 3:16a08969e192 261 i2c.stop();
donghuoyinzi 3:16a08969e192 262 return true;
donghuoyinzi 3:16a08969e192 263 }
donghuoyinzi 3:16a08969e192 264
donghuoyinzi 3:16a08969e192 265 bool I2Cdev::writeWords(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint16_t *data)
donghuoyinzi 3:16a08969e192 266 {
donghuoyinzi 3:16a08969e192 267 return true;
donghuoyinzi 3:16a08969e192 268 }
donghuoyinzi 3:16a08969e192 269
donghuoyinzi 3:16a08969e192 270 uint16_t I2Cdev::readTimeout(void)
donghuoyinzi 3:16a08969e192 271 {
donghuoyinzi 3:16a08969e192 272 return 0;
donghuoyinzi 3:16a08969e192 273 }