Yihui Xiong
/
Seeed_nRF51822_Motion
initial
Diff: mbed-src/api/I2C.h
- Revision:
- 1:9d3b497333c0
- Parent:
- 0:638edba3adf6
--- a/mbed-src/api/I2C.h Mon Jan 11 02:32:24 2016 +0000 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,176 +0,0 @@ -/* mbed Microcontroller Library - * Copyright (c) 2006-2015 ARM Limited - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ -#ifndef MBED_I2C_H -#define MBED_I2C_H - -#include "platform.h" - -#if DEVICE_I2C - -#include "i2c_api.h" - -#if DEVICE_I2C_ASYNCH -#include "CThunk.h" -#include "dma_api.h" -#include "FunctionPointer.h" -#endif - -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); - -#if DEVICE_I2C_ASYNCH - - /** Start non-blocking I2C transfer. - * - * @param address 8/10 bit I2c slave address - * @param tx_buffer The TX buffer with data to be transfered - * @param tx_length The length of TX buffer in bytes - * @param rx_buffer The RX buffer which is used for received data - * @param rx_length The length of RX buffer in bytes - * @param event The logical OR of events to modify - * @param callback The event callback function - * @param repeated Repeated start, true - do not send stop at end - * @return Zero if the transfer has started, or -1 if I2C peripheral is busy - */ - int transfer(int address, const char *tx_buffer, int tx_length, char *rx_buffer, int rx_length, const event_callback_t& callback, int event = I2C_EVENT_TRANSFER_COMPLETE, bool repeated = false); - - /** Abort the on-going I2C transfer - */ - void abort_transfer(); -protected: - void irq_handler_asynch(void); - event_callback_t _callback; - CThunk<I2C> _irq; - DMAUsage _usage; -#endif - -protected: - void aquire(); - - i2c_t _i2c; - static I2C *_owner; - int _hz; -}; - -} // namespace mbed - -#endif - -#endif