mbed library sources modified for open wear
Dependents: openwear-lifelogger-example
Fork of mbed-src by
Diff: cpp/I2C.h
- Revision:
- 0:fd0d7bdfcdc2
- Child:
- 2:143cac498751
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cpp/I2C.h Tue Nov 20 17:24:08 2012 +0000 @@ -0,0 +1,150 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2012 ARM Limited + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ +#ifndef MBED_I2C_H +#define MBED_I2C_H + +#include "platform.h" + +#if DEVICE_I2C + +#include "i2c_api.h" + +namespace mbed { + +/** An I2C Master, used for communicating with I2C slave devices + * + * Example: + * @code + * // Read from I2C slave at address 0x62 + * + * #include "mbed.h" + * + * I2C i2c(p28, p27); + * + * int main() { + * int address = 0x62; + * char data[2]; + * i2c.read(address, data, 2); + * } + * @endcode + */ +class I2C { + +public: + enum RxStatus { + NoData, + MasterGeneralCall, + MasterWrite, + MasterRead + }; + + enum Acknowledge { + NoACK = 0, + ACK = 1 + }; + + /** Create an I2C Master interface, connected to the specified pins + * + * @param sda I2C data line pin + * @param scl I2C clock line pin + */ + I2C(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); + +protected: + void aquire(); + + i2c_t _i2c; + static I2C *_owner; + int _hz; +}; + +} // namespace mbed + +#endif + +#endif