I2CRTOS Driver by Helmut Schmücker. Removed included mbed-rtos library to prevent multiple definition. Make sure to include mbed-rtos library in your program!
Fork of I2cRtosDriver by
I2CDriver.h@7:04824382eafb, 2013-04-28 (annotated)
- Committer:
- humlet
- Date:
- Sun Apr 28 15:08:04 2013 +0000
- Revision:
- 7:04824382eafb
- Parent:
- 6:5b98c902a659
- Child:
- 9:65aae53a34de
stable before perf measurements
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
humlet | 0:13c962fecb13 | 1 | #ifndef I2CDRIVER_H |
humlet | 0:13c962fecb13 | 2 | #define I2CDRIVER_H |
humlet | 0:13c962fecb13 | 3 | |
humlet | 0:13c962fecb13 | 4 | #include "stdint.h" |
humlet | 0:13c962fecb13 | 5 | |
humlet | 0:13c962fecb13 | 6 | #include "I2C.h" |
humlet | 0:13c962fecb13 | 7 | |
humlet | 0:13c962fecb13 | 8 | #include "Thread.h" |
humlet | 0:13c962fecb13 | 9 | #include "Mutex.h" |
humlet | 0:13c962fecb13 | 10 | |
humlet | 0:13c962fecb13 | 11 | namespace mbed |
humlet | 0:13c962fecb13 | 12 | { |
humlet | 5:8a418c89e515 | 13 | /// I2C driver based on mbed RTOS and I2C-C-API. |
humlet | 5:8a418c89e515 | 14 | /// Supports Master and Slave mode |
humlet | 3:967dde37e712 | 15 | class I2CDriver |
humlet | 0:13c962fecb13 | 16 | { |
humlet | 0:13c962fecb13 | 17 | public: |
humlet | 5:8a418c89e515 | 18 | /// Status returned by the receiveSlave() function |
humlet | 3:967dde37e712 | 19 | enum SlaveRxStatus { |
humlet | 3:967dde37e712 | 20 | NoData = 0, |
humlet | 3:967dde37e712 | 21 | ReadAddressed = 1, |
humlet | 3:967dde37e712 | 22 | WriteGeneral = 2, |
humlet | 3:967dde37e712 | 23 | WriteAddressed = 3 |
humlet | 3:967dde37e712 | 24 | }; |
humlet | 0:13c962fecb13 | 25 | |
humlet | 5:8a418c89e515 | 26 | /** Create an I2C Master interface, connected to the specified pins. |
humlet | 0:13c962fecb13 | 27 | * |
humlet | 0:13c962fecb13 | 28 | * @param sda I2C data line pin |
humlet | 0:13c962fecb13 | 29 | * @param scl I2C clock line pin |
humlet | 5:8a418c89e515 | 30 | * |
humlet | 5:8a418c89e515 | 31 | * @note Has to be created in a thread context, i.e. within the main or some other function. A global delaration does not work |
humlet | 0:13c962fecb13 | 32 | */ |
humlet | 3:967dde37e712 | 33 | I2CDriver(PinName sda, PinName scl, int hz=100000, int slaveAdr=0); |
humlet | 3:967dde37e712 | 34 | |
humlet | 3:967dde37e712 | 35 | /** Set the frequency of the I2C interface |
humlet | 3:967dde37e712 | 36 | * |
humlet | 3:967dde37e712 | 37 | * @param hz The bus frequency in hertz |
humlet | 3:967dde37e712 | 38 | */ |
humlet | 3:967dde37e712 | 39 | void frequency(int hz) { |
humlet | 3:967dde37e712 | 40 | m_freq = hz; |
humlet | 3:967dde37e712 | 41 | } |
humlet | 0:13c962fecb13 | 42 | |
humlet | 0:13c962fecb13 | 43 | /** Read from an I2C slave |
humlet | 0:13c962fecb13 | 44 | * |
humlet | 0:13c962fecb13 | 45 | * Performs a complete read transaction. The bottom bit of |
humlet | 0:13c962fecb13 | 46 | * the address is forced to 1 to indicate a read. |
humlet | 0:13c962fecb13 | 47 | * |
humlet | 0:13c962fecb13 | 48 | * @param address 8-bit I2C slave address [ addr | 1 ] |
humlet | 0:13c962fecb13 | 49 | * @param data Pointer to the byte-array to read data in to |
humlet | 0:13c962fecb13 | 50 | * @param length Number of bytes to read |
humlet | 0:13c962fecb13 | 51 | * @param repeated Repeated start, true - don't send stop at end |
humlet | 0:13c962fecb13 | 52 | * |
humlet | 0:13c962fecb13 | 53 | * @returns |
humlet | 0:13c962fecb13 | 54 | * 0 on success (ack), |
humlet | 0:13c962fecb13 | 55 | * non-0 on failure (nack) |
humlet | 0:13c962fecb13 | 56 | */ |
humlet | 7:04824382eafb | 57 | int readMaster(int address, char* data, int length, bool repeated = false); |
humlet | 0:13c962fecb13 | 58 | |
humlet | 3:967dde37e712 | 59 | /** Read from a given I2C slave register |
humlet | 3:967dde37e712 | 60 | * |
humlet | 3:967dde37e712 | 61 | * Performs a complete write-register-read-data-transaction. The bottom bit of |
humlet | 3:967dde37e712 | 62 | * the address is forced to 1 to indicate a read. |
humlet | 3:967dde37e712 | 63 | * |
humlet | 3:967dde37e712 | 64 | * @param address 8-bit I2C slave address [ addr | 1 ] |
humlet | 3:967dde37e712 | 65 | * @param _register 8-bit regster address |
humlet | 3:967dde37e712 | 66 | * @param data Pointer to the byte-array to read data in to |
humlet | 3:967dde37e712 | 67 | * @param length Number of bytes to read |
humlet | 3:967dde37e712 | 68 | * @param repeated Repeated start, true - don't send stop at end |
humlet | 3:967dde37e712 | 69 | * |
humlet | 3:967dde37e712 | 70 | * @returns |
humlet | 3:967dde37e712 | 71 | * 0 on success (ack), |
humlet | 3:967dde37e712 | 72 | * non-0 on failure (nack) |
humlet | 3:967dde37e712 | 73 | */ |
humlet | 7:04824382eafb | 74 | int readMaster(int address, uint8_t _register, char* data, int length, bool repeated = false); |
humlet | 1:90455d5bdd8c | 75 | |
humlet | 0:13c962fecb13 | 76 | /** Read a single byte from the I2C bus |
humlet | 0:13c962fecb13 | 77 | * |
humlet | 0:13c962fecb13 | 78 | * @param ack indicates if the byte is to be acknowledged (1 = acknowledge) |
humlet | 0:13c962fecb13 | 79 | * |
humlet | 0:13c962fecb13 | 80 | * @returns |
humlet | 0:13c962fecb13 | 81 | * the byte read |
humlet | 0:13c962fecb13 | 82 | */ |
humlet | 3:967dde37e712 | 83 | int readMaster(int ack=1); |
humlet | 0:13c962fecb13 | 84 | |
humlet | 0:13c962fecb13 | 85 | /** Write to an I2C slave |
humlet | 0:13c962fecb13 | 86 | * |
humlet | 0:13c962fecb13 | 87 | * Performs a complete write transaction. The bottom bit of |
humlet | 0:13c962fecb13 | 88 | * the address is forced to 0 to indicate a write. |
humlet | 0:13c962fecb13 | 89 | * |
humlet | 0:13c962fecb13 | 90 | * @param address 8-bit I2C slave address [ addr | 0 ] |
humlet | 0:13c962fecb13 | 91 | * @param data Pointer to the byte-array data to send |
humlet | 0:13c962fecb13 | 92 | * @param length Number of bytes to send |
humlet | 0:13c962fecb13 | 93 | * @param repeated Repeated start, true - do not send stop at end |
humlet | 0:13c962fecb13 | 94 | * |
humlet | 0:13c962fecb13 | 95 | * @returns |
humlet | 0:13c962fecb13 | 96 | * 0 on success (ack), |
humlet | 0:13c962fecb13 | 97 | * non-0 on failure (nack) |
humlet | 0:13c962fecb13 | 98 | */ |
humlet | 3:967dde37e712 | 99 | int writeMaster(int address, const char *data, int length, bool repeated = false); |
humlet | 0:13c962fecb13 | 100 | |
humlet | 0:13c962fecb13 | 101 | /** Write single byte out on the I2C bus |
humlet | 0:13c962fecb13 | 102 | * |
humlet | 0:13c962fecb13 | 103 | * @param data data to write out on bus |
humlet | 0:13c962fecb13 | 104 | * |
humlet | 0:13c962fecb13 | 105 | * @returns |
humlet | 0:13c962fecb13 | 106 | * '1' if an ACK was received, |
humlet | 0:13c962fecb13 | 107 | * '0' otherwise |
humlet | 0:13c962fecb13 | 108 | */ |
humlet | 3:967dde37e712 | 109 | int writeMaster(int data); |
humlet | 3:967dde37e712 | 110 | |
humlet | 3:967dde37e712 | 111 | /** Sets the I2C slave address. |
humlet | 3:967dde37e712 | 112 | * |
humlet | 3:967dde37e712 | 113 | * @param address The address to set for the slave (ignoring the least |
humlet | 3:967dde37e712 | 114 | * signifcant bit). If set to 0, the slave will only respond to the |
humlet | 3:967dde37e712 | 115 | * general call address. |
humlet | 3:967dde37e712 | 116 | */ |
humlet | 3:967dde37e712 | 117 | void addressSlave(int address) { |
humlet | 3:967dde37e712 | 118 | m_slaveAdr=address; |
humlet | 3:967dde37e712 | 119 | } |
humlet | 3:967dde37e712 | 120 | |
humlet | 3:967dde37e712 | 121 | /** Checks to see if this I2C Slave has been addressed. |
humlet | 3:967dde37e712 | 122 | * |
humlet | 3:967dde37e712 | 123 | * @returns |
humlet | 3:967dde37e712 | 124 | * A status indicating if the device has been addressed, and how |
humlet | 3:967dde37e712 | 125 | * - NoData - the slave has not been addressed |
humlet | 3:967dde37e712 | 126 | * - ReadAddressed - the master has requested a read from this slave |
humlet | 3:967dde37e712 | 127 | * - WriteAddressed - the master is writing to this slave |
humlet | 3:967dde37e712 | 128 | * - WriteGeneral - the master is writing to all slave |
humlet | 3:967dde37e712 | 129 | */ |
humlet | 3:967dde37e712 | 130 | int receiveSlave(uint32_t timeout_ms=osWaitForever); |
humlet | 3:967dde37e712 | 131 | |
humlet | 3:967dde37e712 | 132 | /** Read from an I2C master. |
humlet | 3:967dde37e712 | 133 | * |
humlet | 3:967dde37e712 | 134 | * @param data pointer to the byte array to read data in to |
humlet | 3:967dde37e712 | 135 | * @param length maximum number of bytes to read |
humlet | 3:967dde37e712 | 136 | * |
humlet | 3:967dde37e712 | 137 | * @returns |
humlet | 3:967dde37e712 | 138 | * 0 on success, |
humlet | 3:967dde37e712 | 139 | * non-0 otherwise |
humlet | 3:967dde37e712 | 140 | */ |
humlet | 3:967dde37e712 | 141 | int readSlave(char *data, int length); |
humlet | 3:967dde37e712 | 142 | |
humlet | 3:967dde37e712 | 143 | /** Read a single byte from an I2C master. |
humlet | 3:967dde37e712 | 144 | * |
humlet | 3:967dde37e712 | 145 | * @returns |
humlet | 3:967dde37e712 | 146 | * the byte read |
humlet | 3:967dde37e712 | 147 | */ |
humlet | 3:967dde37e712 | 148 | int readSlave(void); |
humlet | 3:967dde37e712 | 149 | |
humlet | 3:967dde37e712 | 150 | /** Write to an I2C master. |
humlet | 3:967dde37e712 | 151 | * |
humlet | 3:967dde37e712 | 152 | * @param data pointer to the byte array to be transmitted |
humlet | 3:967dde37e712 | 153 | * @param length the number of bytes to transmite |
humlet | 3:967dde37e712 | 154 | * |
humlet | 3:967dde37e712 | 155 | * @returns |
humlet | 3:967dde37e712 | 156 | * 0 on success, |
humlet | 3:967dde37e712 | 157 | * non-0 otherwise |
humlet | 3:967dde37e712 | 158 | */ |
humlet | 3:967dde37e712 | 159 | int writeSlave(const char *data, int length); |
humlet | 3:967dde37e712 | 160 | |
humlet | 3:967dde37e712 | 161 | /** Write a single byte to an I2C master. |
humlet | 3:967dde37e712 | 162 | * |
humlet | 3:967dde37e712 | 163 | * @data the byte to write |
humlet | 3:967dde37e712 | 164 | * |
humlet | 3:967dde37e712 | 165 | * @returns |
humlet | 3:967dde37e712 | 166 | * '1' if an ACK was received, |
humlet | 3:967dde37e712 | 167 | * '0' otherwise |
humlet | 3:967dde37e712 | 168 | */ |
humlet | 3:967dde37e712 | 169 | int writeSlave(int data); |
humlet | 3:967dde37e712 | 170 | |
humlet | 0:13c962fecb13 | 171 | |
humlet | 0:13c962fecb13 | 172 | /// Creates a start condition on the I2C bus |
humlet | 3:967dde37e712 | 173 | void startMaster(void); |
humlet | 0:13c962fecb13 | 174 | |
humlet | 0:13c962fecb13 | 175 | ///Creates a stop condition on the I2C bus |
humlet | 3:967dde37e712 | 176 | void stopSlave(void); |
humlet | 3:967dde37e712 | 177 | |
humlet | 3:967dde37e712 | 178 | ///Creates a stop condition on the I2C bus |
humlet | 3:967dde37e712 | 179 | void stopMaster(void); |
humlet | 3:967dde37e712 | 180 | |
humlet | 0:13c962fecb13 | 181 | /// Wait until the i2c driver becomes available. |
humlet | 3:967dde37e712 | 182 | /// |
humlet | 3:967dde37e712 | 183 | /// Useful if you want to run a sequence of command without interrution by another thread. |
humlet | 3:967dde37e712 | 184 | /// There's no need to call this function for running single request, because all driver functions |
humlet | 3:967dde37e712 | 185 | /// will lock the device for exclusive access automatically. |
humlet | 6:5b98c902a659 | 186 | void lock(); |
humlet | 0:13c962fecb13 | 187 | |
humlet | 3:967dde37e712 | 188 | /// Unlock the driver that has previously been locked by the same thread. |
humlet | 6:5b98c902a659 | 189 | void unlock(); |
humlet | 0:13c962fecb13 | 190 | |
humlet | 0:13c962fecb13 | 191 | protected: |
humlet | 6:5b98c902a659 | 192 | // commands sent from user to drive thread |
humlet | 0:13c962fecb13 | 193 | enum Command { |
humlet | 0:13c962fecb13 | 194 | START, |
humlet | 0:13c962fecb13 | 195 | STOP, |
humlet | 3:967dde37e712 | 196 | READ_MST, |
humlet | 3:967dde37e712 | 197 | READ_MST_REG, |
humlet | 3:967dde37e712 | 198 | READ_SLV, |
humlet | 0:13c962fecb13 | 199 | READ_BYTE, |
humlet | 3:967dde37e712 | 200 | WRITE_MST, |
humlet | 3:967dde37e712 | 201 | WRITE_SLV, |
humlet | 3:967dde37e712 | 202 | WRITE_BYTE, |
humlet | 3:967dde37e712 | 203 | RECEIVE |
humlet | 1:90455d5bdd8c | 204 | }; |
humlet | 6:5b98c902a659 | 205 | |
humlet | 5:8a418c89e515 | 206 | // data transfer struct for communication between user and driver thread |
humlet | 0:13c962fecb13 | 207 | struct Transfer { |
humlet | 0:13c962fecb13 | 208 | Command cmd; |
humlet | 3:967dde37e712 | 209 | int ret; |
humlet | 0:13c962fecb13 | 210 | int freq; |
humlet | 0:13c962fecb13 | 211 | int adr; |
humlet | 0:13c962fecb13 | 212 | char* dta; |
humlet | 1:90455d5bdd8c | 213 | const char* wdta; |
humlet | 0:13c962fecb13 | 214 | int len; |
humlet | 1:90455d5bdd8c | 215 | int ack; |
humlet | 0:13c962fecb13 | 216 | bool rep; |
humlet | 3:967dde37e712 | 217 | uint8_t reg; |
humlet | 3:967dde37e712 | 218 | bool slv; |
humlet | 3:967dde37e712 | 219 | uint32_t tmout; |
humlet | 3:967dde37e712 | 220 | osThreadId caller; |
humlet | 1:90455d5bdd8c | 221 | }; |
humlet | 0:13c962fecb13 | 222 | |
humlet | 6:5b98c902a659 | 223 | // structure that holds handles/locks for accessing the I2C channels |
humlet | 0:13c962fecb13 | 224 | struct Channel { |
humlet | 6:5b98c902a659 | 225 | osThreadId driver; |
humlet | 1:90455d5bdd8c | 226 | rtos::Mutex mutex; |
humlet | 1:90455d5bdd8c | 227 | volatile Transfer transfer; |
humlet | 1:90455d5bdd8c | 228 | }; |
humlet | 6:5b98c902a659 | 229 | |
humlet | 5:8a418c89e515 | 230 | // current frequency setting |
humlet | 3:967dde37e712 | 231 | int m_freq; |
humlet | 5:8a418c89e515 | 232 | // current slave address setting |
humlet | 3:967dde37e712 | 233 | int m_slaveAdr; |
humlet | 6:5b98c902a659 | 234 | // prio of current caller thread |
humlet | 6:5b98c902a659 | 235 | osPriority m_callerPrio; |
humlet | 6:5b98c902a659 | 236 | // ID of current caller thread |
humlet | 6:5b98c902a659 | 237 | osThreadId m_callerID; |
humlet | 6:5b98c902a659 | 238 | |
humlet | 6:5b98c902a659 | 239 | // i2c driver prio |
humlet | 6:5b98c902a659 | 240 | static const osPriority c_drvPrio = osPriorityRealtime; |
humlet | 5:8a418c89e515 | 241 | // the pin names fo the i2c channels |
humlet | 1:90455d5bdd8c | 242 | static const PinName c_sdas[2]; |
humlet | 1:90455d5bdd8c | 243 | static const PinName c_scls[2]; |
humlet | 0:13c962fecb13 | 244 | |
humlet | 6:5b98c902a659 | 245 | // static storage for the I2C channel access objects |
humlet | 2:514105beb343 | 246 | static Channel* s_channels[2]; |
humlet | 6:5b98c902a659 | 247 | |
humlet | 5:8a418c89e515 | 248 | // i2c channel object of this driver interface, in fact just pointer |
humlet | 5:8a418c89e515 | 249 | /// to one of the entries in s_channels |
humlet | 2:514105beb343 | 250 | Channel* m_channel; |
humlet | 6:5b98c902a659 | 251 | |
humlet | 6:5b98c902a659 | 252 | // ISRs |
humlet | 0:13c962fecb13 | 253 | static void channel_0_ISR(); |
humlet | 0:13c962fecb13 | 254 | static void channel_1_ISR(); |
humlet | 6:5b98c902a659 | 255 | |
humlet | 5:8a418c89e515 | 256 | // the driver thread function |
humlet | 1:90455d5bdd8c | 257 | static void threadFun(void const *args); |
humlet | 6:5b98c902a659 | 258 | |
humlet | 3:967dde37e712 | 259 | int sendNwait(); |
humlet | 1:90455d5bdd8c | 260 | }; |
humlet | 0:13c962fecb13 | 261 | } |
humlet | 0:13c962fecb13 | 262 | #endif |