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
Diff: I2CDriver.h
- Revision:
- 0:13c962fecb13
- Child:
- 1:90455d5bdd8c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/I2CDriver.h Sat Apr 13 13:37:29 2013 +0000 @@ -0,0 +1,152 @@ +#ifndef I2CDRIVER_H +#define I2CDRIVER_H + +#include "stdint.h" + +#include "I2C.h" + +#include "Thread.h" +#include "Semaphore.h" +#include "Mutex.h" + +namespace mbed +{ + +class I2CDriver : protected I2C +{ +public: + using I2C::RxStatus; + using I2C::Acknowledge; + using I2C::frequency; + + /** Create an I2C Master interface, connected to the specified pins + * + * @param sda I2C data line pin + * @param scl I2C clock line pin + */ + I2CDriver(PinName sda, PinName scl); + + /** Set the frequency of the I2C interface + * + * @param hz The bus frequency in hertz + */ + void frequency(int hz); + + /** Read from an I2C slave + * + * Performs a complete read transaction. The bottom bit of + * the address is forced to 1 to indicate a read. + * + * @param address 8-bit I2C slave address [ addr | 1 ] + * @param data Pointer to the byte-array to read data in to + * @param length Number of bytes to read + * @param repeated Repeated start, true - don't send stop at end + * + * @returns + * 0 on success (ack), + * non-0 on failure (nack) + */ + int read(int address, char *data, int length, bool repeated = false); + + /** Read a single byte from the I2C bus + * + * @param ack indicates if the byte is to be acknowledged (1 = acknowledge) + * + * @returns + * the byte read + */ + int read(int ack); + + /** Write to an I2C slave + * + * Performs a complete write transaction. The bottom bit of + * the address is forced to 0 to indicate a write. + * + * @param address 8-bit I2C slave address [ addr | 0 ] + * @param data Pointer to the byte-array data to send + * @param length Number of bytes to send + * @param repeated Repeated start, true - do not send stop at end + * + * @returns + * 0 on success (ack), + * non-0 on failure (nack) + */ + int write(int address, const char *data, int length, bool repeated = false); + + /** Write single byte out on the I2C bus + * + * @param data data to write out on bus + * + * @returns + * '1' if an ACK was received, + * '0' otherwise + */ + int write(int data); + + /// Creates a start condition on the I2C bus + void start(void); + + ///Creates a stop condition on the I2C bus + void stop(void); + + /// Wait until the i2c driver becomes available. + void lock() { + // if one and the same thread can lock twice, but then it needs also to unlock twice. + // exactly what we need here + m_channel.mutex.lock(osWaitForever); + } + + /// Unlock the driver that has previously been locked by the same thread + void osStatus unlock() { + m_channel.mutex.unlock(osWaitForever); + } + + +protected: + + enum Command { + START, + STOP, + WRITE_BYTE, + WRITE, + READ_BYTE, + READ, + READ_FROM_REGISTER + } + + struct Transfer { + Command cmd; + int freq; + int adr; + int reg; + char* dta; + int len; + bool rep; + int res; + } + + struct Channel { + osThreadId caller; + osThreadId driver; + Mutex mutex; + Transfer transfer; + int freq; + } + + static const PinName c_sda[]= {p9,p28}; + static const PinName c_scl[]= {p10,p27}; + + static Channel* s_channels[2]; + + Channel& m_channel; + + static void channel_0_ISR(); + static void channel_1_ISR(); + + static void threadFun(void* const args); + + void sendNwait(); + +} +} +#endif