GRT_FS2019_VoiceCoil / MPU6050

IMU Library

Dependents:   Cube_Mini_Solution Cube_Mini_Solution

I2Cdev.cpp@2:8c562a8fed36, 2014-09-12 (annotated)

Committer:
Yihui Xiong
Date:
Fri Sep 12 09:28:14 2014 +0800
Revision:
2:8c562a8fed36
Parent:
1:1e0baaf91e96 
update

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
garfieldsg 0:662207e34fba 8
Yihui Xiong 2:8c562a8fed36 9 I2Cdev::I2Cdev(I2C &interface) : i2c(interface)
garfieldsg 0:662207e34fba 10 {
garfieldsg 0:662207e34fba 11
garfieldsg 0:662207e34fba 12 }
garfieldsg 0:662207e34fba 13
garfieldsg 0:662207e34fba 14 /** Read a single bit from an 8-bit device register.
garfieldsg 0:662207e34fba 15 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 16 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 17 * @param bitNum Bit position to read (0-7)
garfieldsg 0:662207e34fba 18 * @param data Container for single bit value
garfieldsg 0:662207e34fba 19 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 20 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 21 */
garfieldsg 0:662207e34fba 22 int8_t I2Cdev::readBit(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint8_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 23 uint8_t b;
garfieldsg 0:662207e34fba 24 uint8_t count = readByte(devAddr, regAddr, &b, timeout);
garfieldsg 0:662207e34fba 25 *data = b & (1 << bitNum);
garfieldsg 0:662207e34fba 26 return count;
garfieldsg 0:662207e34fba 27 }
garfieldsg 0:662207e34fba 28
garfieldsg 0:662207e34fba 29 /** Read a single bit from a 16-bit device register.
garfieldsg 0:662207e34fba 30 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 31 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 32 * @param bitNum Bit position to read (0-15)
garfieldsg 0:662207e34fba 33 * @param data Container for single bit value
garfieldsg 0:662207e34fba 34 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 35 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 36 */
garfieldsg 0:662207e34fba 37 int8_t I2Cdev::readBitW(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint16_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 38 uint16_t b;
garfieldsg 0:662207e34fba 39 uint8_t count = readWord(devAddr, regAddr, &b, timeout);
garfieldsg 0:662207e34fba 40 *data = b & (1 << bitNum);
garfieldsg 0:662207e34fba 41 return count;
garfieldsg 0:662207e34fba 42 }
garfieldsg 0:662207e34fba 43
garfieldsg 0:662207e34fba 44 /** Read multiple bits from an 8-bit device register.
garfieldsg 0:662207e34fba 45 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 46 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 47 * @param bitStart First bit position to read (0-7)
garfieldsg 0:662207e34fba 48 * @param length Number of bits to read (not more than 8)
garfieldsg 0:662207e34fba 49 * @param data Container for right-aligned value (i.e. '101' read from any bitStart position will equal 0x05)
garfieldsg 0:662207e34fba 50 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 51 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 52 */
garfieldsg 0:662207e34fba 53 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 54 // 01101001 read byte
garfieldsg 0:662207e34fba 55 // 76543210 bit numbers
garfieldsg 0:662207e34fba 56 // xxx args: bitStart=4, length=3
garfieldsg 0:662207e34fba 57 // 010 masked
garfieldsg 0:662207e34fba 58 // -> 010 shifted
garfieldsg 0:662207e34fba 59 uint8_t count, b;
garfieldsg 0:662207e34fba 60 if ((count = readByte(devAddr, regAddr, &b, timeout)) != 0) {
garfieldsg 0:662207e34fba 61 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
garfieldsg 0:662207e34fba 62 b &= mask;
garfieldsg 0:662207e34fba 63 b >>= (bitStart - length + 1);
garfieldsg 0:662207e34fba 64 *data = b;
garfieldsg 0:662207e34fba 65 }
garfieldsg 0:662207e34fba 66 return count;
garfieldsg 0:662207e34fba 67 }
garfieldsg 0:662207e34fba 68
garfieldsg 0:662207e34fba 69 /** Read multiple bits from a 16-bit device register.
garfieldsg 0:662207e34fba 70 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 71 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 72 * @param bitStart First bit position to read (0-15)
garfieldsg 0:662207e34fba 73 * @param length Number of bits to read (not more than 16)
garfieldsg 0:662207e34fba 74 * @param data Container for right-aligned value (i.e. '101' read from any bitStart position will equal 0x05)
garfieldsg 0:662207e34fba 75 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 76 * @return Status of read operation (1 = success, 0 = failure, -1 = timeout)
garfieldsg 0:662207e34fba 77 */
garfieldsg 0:662207e34fba 78 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 79 // 1101011001101001 read byte
garfieldsg 0:662207e34fba 80 // fedcba9876543210 bit numbers
garfieldsg 0:662207e34fba 81 // xxx args: bitStart=12, length=3
garfieldsg 0:662207e34fba 82 // 010 masked
garfieldsg 0:662207e34fba 83 // -> 010 shifted
garfieldsg 0:662207e34fba 84 uint8_t count;
garfieldsg 0:662207e34fba 85 uint16_t w;
garfieldsg 0:662207e34fba 86 if ((count = readWord(devAddr, regAddr, &w, timeout)) != 0) {
garfieldsg 0:662207e34fba 87 uint16_t mask = ((1 << length) - 1) << (bitStart - length + 1);
garfieldsg 0:662207e34fba 88 w &= mask;
garfieldsg 0:662207e34fba 89 w >>= (bitStart - length + 1);
garfieldsg 0:662207e34fba 90 *data = w;
garfieldsg 0:662207e34fba 91 }
garfieldsg 0:662207e34fba 92 return count;
garfieldsg 0:662207e34fba 93 }
garfieldsg 0:662207e34fba 94 /** Read single byte from an 8-bit device register.
garfieldsg 0:662207e34fba 95 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 96 * @param regAddr Register regAddr to read from
garfieldsg 0:662207e34fba 97 * @param data Container for byte value read from device
garfieldsg 0:662207e34fba 98 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 99 * @return Status of read operation (true = success)
garfieldsg 0:662207e34fba 100 */
garfieldsg 0:662207e34fba 101 int8_t I2Cdev::readByte(uint8_t devAddr, uint8_t regAddr, uint8_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 102 return readBytes(devAddr, regAddr, 1, data, timeout);
garfieldsg 0:662207e34fba 103 }
garfieldsg 0:662207e34fba 104
garfieldsg 0:662207e34fba 105 /** Read single word from a 16-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 word 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::readWord(uint8_t devAddr, uint8_t regAddr, uint16_t *data, uint16_t timeout) {
garfieldsg 0:662207e34fba 113 return readWords(devAddr, regAddr, 1, data, timeout);
garfieldsg 0:662207e34fba 114 }
garfieldsg 0:662207e34fba 115
garfieldsg 0:662207e34fba 116 /** Read multiple bytes from an 8-bit device register.
garfieldsg 0:662207e34fba 117 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 118 * @param regAddr First register regAddr to read from
garfieldsg 0:662207e34fba 119 * @param length Number of bytes to read
garfieldsg 0:662207e34fba 120 * @param data Buffer to store read data in
garfieldsg 0:662207e34fba 121 * @param timeout Optional read timeout in milliseconds (0 to disable, leave off to use default class value in I2Cdev::readTimeout)
garfieldsg 0:662207e34fba 122 * @return Number of bytes read (-1 indicates failure)
garfieldsg 0:662207e34fba 123 */
garfieldsg 0:662207e34fba 124 int8_t I2Cdev::readBytes(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint8_t *data, uint16_t timeout)
garfieldsg 0:662207e34fba 125 {
garfieldsg 0:662207e34fba 126 char command[1];
garfieldsg 0:662207e34fba 127 command[0] = regAddr;
garfieldsg 0:662207e34fba 128 char *redData = (char*)malloc(length);
garfieldsg 0:662207e34fba 129 i2c.write(devAddr<<1, command, 1, true);
garfieldsg 0:662207e34fba 130 i2c.read(devAddr<<1, redData, length);
garfieldsg 0:662207e34fba 131 for(int i =0; i < length; i++) {
garfieldsg 0:662207e34fba 132 data[i] = redData[i];
garfieldsg 0:662207e34fba 133 }
garfieldsg 1:1e0baaf91e96 134 free (redData);
garfieldsg 0:662207e34fba 135 return length;
garfieldsg 0:662207e34fba 136 }
garfieldsg 0:662207e34fba 137
garfieldsg 0:662207e34fba 138 int8_t I2Cdev::readWords(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint16_t *data, uint16_t timeout)
garfieldsg 0:662207e34fba 139 {
garfieldsg 0:662207e34fba 140 return 0;
garfieldsg 0:662207e34fba 141 }
garfieldsg 0:662207e34fba 142
garfieldsg 0:662207e34fba 143 /** write a single bit in an 8-bit device register.
garfieldsg 0:662207e34fba 144 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 145 * @param regAddr Register regAddr to write to
garfieldsg 0:662207e34fba 146 * @param bitNum Bit position to write (0-7)
garfieldsg 0:662207e34fba 147 * @param value New bit value to write
garfieldsg 0:662207e34fba 148 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 149 */
garfieldsg 0:662207e34fba 150 bool I2Cdev::writeBit(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint8_t data) {
garfieldsg 0:662207e34fba 151 uint8_t b;
garfieldsg 0:662207e34fba 152 readByte(devAddr, regAddr, &b);
garfieldsg 0:662207e34fba 153 b = (data != 0) ? (b | (1 << bitNum)) : (b & ~(1 << bitNum));
garfieldsg 0:662207e34fba 154 return writeByte(devAddr, regAddr, b);
garfieldsg 0:662207e34fba 155 }
garfieldsg 0:662207e34fba 156
garfieldsg 0:662207e34fba 157 /** write a single bit in a 16-bit device register.
garfieldsg 0:662207e34fba 158 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 159 * @param regAddr Register regAddr to write to
garfieldsg 0:662207e34fba 160 * @param bitNum Bit position to write (0-15)
garfieldsg 0:662207e34fba 161 * @param value New bit value to write
garfieldsg 0:662207e34fba 162 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 163 */
garfieldsg 0:662207e34fba 164 bool I2Cdev::writeBitW(uint8_t devAddr, uint8_t regAddr, uint8_t bitNum, uint16_t data) {
garfieldsg 0:662207e34fba 165 uint16_t w;
garfieldsg 0:662207e34fba 166 readWord(devAddr, regAddr, &w);
garfieldsg 0:662207e34fba 167 w = (data != 0) ? (w | (1 << bitNum)) : (w & ~(1 << bitNum));
garfieldsg 0:662207e34fba 168 return writeWord(devAddr, regAddr, w);
garfieldsg 0:662207e34fba 169 }
garfieldsg 0:662207e34fba 170
garfieldsg 0:662207e34fba 171 /** Write multiple bits in an 8-bit device register.
garfieldsg 0:662207e34fba 172 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 173 * @param regAddr Register regAddr to write to
garfieldsg 0:662207e34fba 174 * @param bitStart First bit position to write (0-7)
garfieldsg 0:662207e34fba 175 * @param length Number of bits to write (not more than 8)
garfieldsg 0:662207e34fba 176 * @param data Right-aligned value to write
garfieldsg 0:662207e34fba 177 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 178 */
garfieldsg 0:662207e34fba 179 bool I2Cdev::writeBits(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint8_t data) {
garfieldsg 0:662207e34fba 180 // 010 value to write
garfieldsg 0:662207e34fba 181 // 76543210 bit numbers
garfieldsg 0:662207e34fba 182 // xxx args: bitStart=4, length=3
garfieldsg 0:662207e34fba 183 // 00011100 mask byte
garfieldsg 0:662207e34fba 184 // 10101111 original value (sample)
garfieldsg 0:662207e34fba 185 // 10100011 original & ~mask
garfieldsg 0:662207e34fba 186 // 10101011 masked | value
garfieldsg 0:662207e34fba 187 uint8_t b;
garfieldsg 0:662207e34fba 188 if (readByte(devAddr, regAddr, &b) != 0) {
garfieldsg 0:662207e34fba 189 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
garfieldsg 0:662207e34fba 190 data <<= (bitStart - length + 1); // shift data into correct position
garfieldsg 0:662207e34fba 191 data &= mask; // zero all non-important bits in data
garfieldsg 0:662207e34fba 192 b &= ~(mask); // zero all important bits in existing byte
garfieldsg 0:662207e34fba 193 b |= data; // combine data with existing byte
garfieldsg 0:662207e34fba 194 return writeByte(devAddr, regAddr, b);
garfieldsg 0:662207e34fba 195 } else {
garfieldsg 0:662207e34fba 196 return false;
garfieldsg 0:662207e34fba 197 }
garfieldsg 0:662207e34fba 198 }
garfieldsg 0:662207e34fba 199
garfieldsg 0:662207e34fba 200 /** Write multiple bits in a 16-bit device register.
garfieldsg 0:662207e34fba 201 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 202 * @param regAddr Register regAddr to write to
garfieldsg 0:662207e34fba 203 * @param bitStart First bit position to write (0-15)
garfieldsg 0:662207e34fba 204 * @param length Number of bits to write (not more than 16)
garfieldsg 0:662207e34fba 205 * @param data Right-aligned value to write
garfieldsg 0:662207e34fba 206 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 207 */
garfieldsg 0:662207e34fba 208 bool I2Cdev::writeBitsW(uint8_t devAddr, uint8_t regAddr, uint8_t bitStart, uint8_t length, uint16_t data) {
garfieldsg 0:662207e34fba 209 // 010 value to write
garfieldsg 0:662207e34fba 210 // fedcba9876543210 bit numbers
garfieldsg 0:662207e34fba 211 // xxx args: bitStart=12, length=3
garfieldsg 0:662207e34fba 212 // 0001110000000000 mask byte
garfieldsg 0:662207e34fba 213 // 1010111110010110 original value (sample)
garfieldsg 0:662207e34fba 214 // 1010001110010110 original & ~mask
garfieldsg 0:662207e34fba 215 // 1010101110010110 masked | value
garfieldsg 0:662207e34fba 216 uint16_t w;
garfieldsg 0:662207e34fba 217 if (readWord(devAddr, regAddr, &w) != 0) {
garfieldsg 0:662207e34fba 218 uint8_t mask = ((1 << length) - 1) << (bitStart - length + 1);
garfieldsg 0:662207e34fba 219 data <<= (bitStart - length + 1); // shift data into correct position
garfieldsg 0:662207e34fba 220 data &= mask; // zero all non-important bits in data
garfieldsg 0:662207e34fba 221 w &= ~(mask); // zero all important bits in existing word
garfieldsg 0:662207e34fba 222 w |= data; // combine data with existing word
garfieldsg 0:662207e34fba 223 return writeWord(devAddr, regAddr, w);
garfieldsg 0:662207e34fba 224 } else {
garfieldsg 0:662207e34fba 225 return false;
garfieldsg 0:662207e34fba 226 }
garfieldsg 0:662207e34fba 227 }
garfieldsg 0:662207e34fba 228
garfieldsg 0:662207e34fba 229 /** Write single byte to an 8-bit device register.
garfieldsg 0:662207e34fba 230 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 231 * @param regAddr Register address to write to
garfieldsg 0:662207e34fba 232 * @param data New byte value to write
garfieldsg 0:662207e34fba 233 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 234 */
garfieldsg 0:662207e34fba 235 bool I2Cdev::writeByte(uint8_t devAddr, uint8_t regAddr, uint8_t data) {
garfieldsg 0:662207e34fba 236 return writeBytes(devAddr, regAddr, 1, &data);
garfieldsg 0:662207e34fba 237 }
garfieldsg 0:662207e34fba 238
garfieldsg 0:662207e34fba 239 /** Write single word to a 16-bit device register.
garfieldsg 0:662207e34fba 240 * @param devAddr I2C slave device address
garfieldsg 0:662207e34fba 241 * @param regAddr Register address to write to
garfieldsg 0:662207e34fba 242 * @param data New word value to write
garfieldsg 0:662207e34fba 243 * @return Status of operation (true = success)
garfieldsg 0:662207e34fba 244 */
garfieldsg 0:662207e34fba 245 bool I2Cdev::writeWord(uint8_t devAddr, uint8_t regAddr, uint16_t data) {
garfieldsg 0:662207e34fba 246 return writeWords(devAddr, regAddr, 1, &data);
garfieldsg 0:662207e34fba 247 }
garfieldsg 0:662207e34fba 248
garfieldsg 0:662207e34fba 249 bool I2Cdev::writeBytes(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint8_t *data)
garfieldsg 0:662207e34fba 250 {
Yihui Xiong 2:8c562a8fed36 251 int len = length + 1;
Yihui Xiong 2:8c562a8fed36 252 char *buf = (char*)malloc(len);
Yihui Xiong 2:8c562a8fed36 253 buf[0] = regAddr;
Yihui Xiong 2:8c562a8fed36 254 for (int i = 0; i < length; i++) {
Yihui Xiong 2:8c562a8fed36 255 buf[i + 1] = data[i];
garfieldsg 0:662207e34fba 256 }
Yihui Xiong 2:8c562a8fed36 257 i2c.write(devAddr << 1 , buf, len);
Yihui Xiong 2:8c562a8fed36 258
Yihui Xiong 2:8c562a8fed36 259 free (buf);
garfieldsg 0:662207e34fba 260 return true;
garfieldsg 0:662207e34fba 261 }
garfieldsg 0:662207e34fba 262
garfieldsg 0:662207e34fba 263 bool I2Cdev::writeWords(uint8_t devAddr, uint8_t regAddr, uint8_t length, uint16_t *data)
garfieldsg 0:662207e34fba 264 {
Yihui Xiong 2:8c562a8fed36 265 int len = length * 2 + 1;
Yihui Xiong 2:8c562a8fed36 266 char *buf = (char*)malloc(len);
Yihui Xiong 2:8c562a8fed36 267 buf[0] = regAddr;
Yihui Xiong 2:8c562a8fed36 268 for (int i = 0; i < length; i++) {
Yihui Xiong 2:8c562a8fed36 269 uint16_t word = data[i];
Yihui Xiong 2:8c562a8fed36 270 buf[2*i + 1] = word >> 8;
Yihui Xiong 2:8c562a8fed36 271 buf[2*i + 2] = word & 0xFF;
Yihui Xiong 2:8c562a8fed36 272 }
Yihui Xiong 2:8c562a8fed36 273 i2c.write(devAddr << 1 , buf, len);
Yihui Xiong 2:8c562a8fed36 274
Yihui Xiong 2:8c562a8fed36 275 free (buf);
garfieldsg 0:662207e34fba 276 return true;
garfieldsg 0:662207e34fba 277 }
garfieldsg 0:662207e34fba 278
garfieldsg 0:662207e34fba 279 uint16_t I2Cdev::readTimeout(void)
garfieldsg 0:662207e34fba 280 {
garfieldsg 0:662207e34fba 281 return 0;
garfieldsg 0:662207e34fba 282 }