From aa30a51f3e2d9120aa819c1bc8162793662ccf32 Mon Sep 17 00:00:00 2001 From: Yann Herklotz Date: Wed, 10 May 2017 13:17:31 +0100 Subject: Adding initial files --- mbed/drivers/I2CSlave.h | 160 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 160 insertions(+) create mode 100644 mbed/drivers/I2CSlave.h (limited to 'mbed/drivers/I2CSlave.h') diff --git a/mbed/drivers/I2CSlave.h b/mbed/drivers/I2CSlave.h new file mode 100644 index 0000000..352b054 --- /dev/null +++ b/mbed/drivers/I2CSlave.h @@ -0,0 +1,160 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2013 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_SLAVE_H +#define MBED_I2C_SLAVE_H + +#include "platform/platform.h" + +#if DEVICE_I2CSLAVE + +#include "hal/i2c_api.h" + +namespace mbed { +/** \addtogroup drivers */ +/** @{*/ + +/** An I2C Slave, used for communicating with an I2C Master device + * + * @Note Synchronization level: Not protected + * + * Example: + * @code + * // Simple I2C responder + * #include + * + * I2CSlave slave(p9, p10); + * + * int main() { + * char buf[10]; + * char msg[] = "Slave!"; + * + * slave.address(0xA0); + * while (1) { + * int i = slave.receive(); + * switch (i) { + * case I2CSlave::ReadAddressed: + * slave.write(msg, strlen(msg) + 1); // Includes null char + * break; + * case I2CSlave::WriteGeneral: + * slave.read(buf, 10); + * printf("Read G: %s\n", buf); + * break; + * case I2CSlave::WriteAddressed: + * slave.read(buf, 10); + * printf("Read A: %s\n", buf); + * break; + * } + * for(int i = 0; i < 10; i++) buf[i] = 0; // Clear buffer + * } + * } + * @endcode + */ +class I2CSlave { + +public: + enum RxStatus { + NoData = 0, + ReadAddressed = 1, + WriteGeneral = 2, + WriteAddressed = 3 + }; + + /** Create an I2C Slave interface, connected to the specified pins. + * + * @param sda I2C data line pin + * @param scl I2C clock line pin + */ + I2CSlave(PinName sda, PinName scl); + + /** Set the frequency of the I2C interface + * + * @param hz The bus frequency in hertz + */ + void frequency(int hz); + + /** Checks to see if this I2C Slave has been addressed. + * + * @returns + * A status indicating if the device has been addressed, and how + * - NoData - the slave has not been addressed + * - ReadAddressed - the master has requested a read from this slave + * - WriteAddressed - the master is writing to this slave + * - WriteGeneral - the master is writing to all slave + */ + int receive(void); + + /** Read from an I2C master. + * + * @param data pointer to the byte array to read data in to + * @param length maximum number of bytes to read + * + * @returns + * 0 on success, + * non-0 otherwise + */ + int read(char *data, int length); + + /** Read a single byte from an I2C master. + * + * @returns + * the byte read + */ + int read(void); + + /** Write to an I2C master. + * + * @param data pointer to the byte array to be transmitted + * @param length the number of bytes to transmite + * + * @returns + * 0 on success, + * non-0 otherwise + */ + int write(const char *data, int length); + + /** Write a single byte to an I2C master. + * + * @data the byte to write + * + * @returns + * '1' if an ACK was received, + * '0' otherwise + */ + int write(int data); + + /** Sets the I2C slave address. + * + * @param address The address to set for the slave (ignoring the least + * signifcant bit). If set to 0, the slave will only respond to the + * general call address. + */ + void address(int address); + + /** Reset the I2C slave back into the known ready receiving state. + */ + void stop(void); + +protected: + i2c_t _i2c; +}; + +} // namespace mbed + +#endif + +#endif + +/** @}*/ -- cgit