EL4121 Embedded System / mbed-os

mbed-os

Dependents:   cobaLCDJoyMotor_Thread odometry_omni_3roda_v3 odometry_omni_3roda_v1 odometry_omni_3roda_v2 ... more

drivers/I2CSlave.h@0:b74591d5ab33, 2017-12-11 (annotated)

Committer:
be_bryan
Date:
Mon Dec 11 17:54:04 2017 +0000
Revision:
0:b74591d5ab33
motor ++

Who changed what in which revision?

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be_bryan 0:b74591d5ab33 1 /* mbed Microcontroller Library
be_bryan 0:b74591d5ab33 2 * Copyright (c) 2006-2013 ARM Limited
be_bryan 0:b74591d5ab33 3 *
be_bryan 0:b74591d5ab33 4 * Licensed under the Apache License, Version 2.0 (the "License");
be_bryan 0:b74591d5ab33 5 * you may not use this file except in compliance with the License.
be_bryan 0:b74591d5ab33 6 * You may obtain a copy of the License at
be_bryan 0:b74591d5ab33 7 *
be_bryan 0:b74591d5ab33 8 * http://www.apache.org/licenses/LICENSE-2.0
be_bryan 0:b74591d5ab33 9 *
be_bryan 0:b74591d5ab33 10 * Unless required by applicable law or agreed to in writing, software
be_bryan 0:b74591d5ab33 11 * distributed under the License is distributed on an "AS IS" BASIS,
be_bryan 0:b74591d5ab33 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
be_bryan 0:b74591d5ab33 13 * See the License for the specific language governing permissions and
be_bryan 0:b74591d5ab33 14 * limitations under the License.
be_bryan 0:b74591d5ab33 15 */
be_bryan 0:b74591d5ab33 16 #ifndef MBED_I2C_SLAVE_H
be_bryan 0:b74591d5ab33 17 #define MBED_I2C_SLAVE_H
be_bryan 0:b74591d5ab33 18
be_bryan 0:b74591d5ab33 19 #include "platform/platform.h"
be_bryan 0:b74591d5ab33 20
be_bryan 0:b74591d5ab33 21 #if defined (DEVICE_I2CSLAVE) || defined(DOXYGEN_ONLY)
be_bryan 0:b74591d5ab33 22
be_bryan 0:b74591d5ab33 23 #include "hal/i2c_api.h"
be_bryan 0:b74591d5ab33 24
be_bryan 0:b74591d5ab33 25 namespace mbed {
be_bryan 0:b74591d5ab33 26 /** \addtogroup drivers */
be_bryan 0:b74591d5ab33 27
be_bryan 0:b74591d5ab33 28 /** An I2C Slave, used for communicating with an I2C Master device
be_bryan 0:b74591d5ab33 29 *
be_bryan 0:b74591d5ab33 30 * @note Synchronization level: Not protected
be_bryan 0:b74591d5ab33 31 *
be_bryan 0:b74591d5ab33 32 * Example:
be_bryan 0:b74591d5ab33 33 * @code
be_bryan 0:b74591d5ab33 34 * // Simple I2C responder
be_bryan 0:b74591d5ab33 35 * #include <mbed.h>
be_bryan 0:b74591d5ab33 36 *
be_bryan 0:b74591d5ab33 37 * I2CSlave slave(p9, p10);
be_bryan 0:b74591d5ab33 38 *
be_bryan 0:b74591d5ab33 39 * int main() {
be_bryan 0:b74591d5ab33 40 * char buf[10];
be_bryan 0:b74591d5ab33 41 * char msg[] = "Slave!";
be_bryan 0:b74591d5ab33 42 *
be_bryan 0:b74591d5ab33 43 * slave.address(0xA0);
be_bryan 0:b74591d5ab33 44 * while (1) {
be_bryan 0:b74591d5ab33 45 * int i = slave.receive();
be_bryan 0:b74591d5ab33 46 * switch (i) {
be_bryan 0:b74591d5ab33 47 * case I2CSlave::ReadAddressed:
be_bryan 0:b74591d5ab33 48 * slave.write(msg, strlen(msg) + 1); // Includes null char
be_bryan 0:b74591d5ab33 49 * break;
be_bryan 0:b74591d5ab33 50 * case I2CSlave::WriteGeneral:
be_bryan 0:b74591d5ab33 51 * slave.read(buf, 10);
be_bryan 0:b74591d5ab33 52 * printf("Read G: %s\n", buf);
be_bryan 0:b74591d5ab33 53 * break;
be_bryan 0:b74591d5ab33 54 * case I2CSlave::WriteAddressed:
be_bryan 0:b74591d5ab33 55 * slave.read(buf, 10);
be_bryan 0:b74591d5ab33 56 * printf("Read A: %s\n", buf);
be_bryan 0:b74591d5ab33 57 * break;
be_bryan 0:b74591d5ab33 58 * }
be_bryan 0:b74591d5ab33 59 * for(int i = 0; i < 10; i++) buf[i] = 0; // Clear buffer
be_bryan 0:b74591d5ab33 60 * }
be_bryan 0:b74591d5ab33 61 * }
be_bryan 0:b74591d5ab33 62 * @endcode
be_bryan 0:b74591d5ab33 63 * @ingroup drivers
be_bryan 0:b74591d5ab33 64 */
be_bryan 0:b74591d5ab33 65 class I2CSlave {
be_bryan 0:b74591d5ab33 66
be_bryan 0:b74591d5ab33 67 public:
be_bryan 0:b74591d5ab33 68 enum RxStatus {
be_bryan 0:b74591d5ab33 69 NoData = 0,
be_bryan 0:b74591d5ab33 70 ReadAddressed = 1,
be_bryan 0:b74591d5ab33 71 WriteGeneral = 2,
be_bryan 0:b74591d5ab33 72 WriteAddressed = 3
be_bryan 0:b74591d5ab33 73 };
be_bryan 0:b74591d5ab33 74
be_bryan 0:b74591d5ab33 75 /** Create an I2C Slave interface, connected to the specified pins.
be_bryan 0:b74591d5ab33 76 *
be_bryan 0:b74591d5ab33 77 * @param sda I2C data line pin
be_bryan 0:b74591d5ab33 78 * @param scl I2C clock line pin
be_bryan 0:b74591d5ab33 79 */
be_bryan 0:b74591d5ab33 80 I2CSlave(PinName sda, PinName scl);
be_bryan 0:b74591d5ab33 81
be_bryan 0:b74591d5ab33 82 /** Set the frequency of the I2C interface
be_bryan 0:b74591d5ab33 83 *
be_bryan 0:b74591d5ab33 84 * @param hz The bus frequency in hertz
be_bryan 0:b74591d5ab33 85 */
be_bryan 0:b74591d5ab33 86 void frequency(int hz);
be_bryan 0:b74591d5ab33 87
be_bryan 0:b74591d5ab33 88 /** Checks to see if this I2C Slave has been addressed.
be_bryan 0:b74591d5ab33 89 *
be_bryan 0:b74591d5ab33 90 * @returns
be_bryan 0:b74591d5ab33 91 * A status indicating if the device has been addressed, and how
be_bryan 0:b74591d5ab33 92 * - NoData - the slave has not been addressed
be_bryan 0:b74591d5ab33 93 * - ReadAddressed - the master has requested a read from this slave
be_bryan 0:b74591d5ab33 94 * - WriteAddressed - the master is writing to this slave
be_bryan 0:b74591d5ab33 95 * - WriteGeneral - the master is writing to all slave
be_bryan 0:b74591d5ab33 96 */
be_bryan 0:b74591d5ab33 97 int receive(void);
be_bryan 0:b74591d5ab33 98
be_bryan 0:b74591d5ab33 99 /** Read from an I2C master.
be_bryan 0:b74591d5ab33 100 *
be_bryan 0:b74591d5ab33 101 * @param data pointer to the byte array to read data in to
be_bryan 0:b74591d5ab33 102 * @param length maximum number of bytes to read
be_bryan 0:b74591d5ab33 103 *
be_bryan 0:b74591d5ab33 104 * @returns
be_bryan 0:b74591d5ab33 105 * 0 on success,
be_bryan 0:b74591d5ab33 106 * non-0 otherwise
be_bryan 0:b74591d5ab33 107 */
be_bryan 0:b74591d5ab33 108 int read(char *data, int length);
be_bryan 0:b74591d5ab33 109
be_bryan 0:b74591d5ab33 110 /** Read a single byte from an I2C master.
be_bryan 0:b74591d5ab33 111 *
be_bryan 0:b74591d5ab33 112 * @returns
be_bryan 0:b74591d5ab33 113 * the byte read
be_bryan 0:b74591d5ab33 114 */
be_bryan 0:b74591d5ab33 115 int read(void);
be_bryan 0:b74591d5ab33 116
be_bryan 0:b74591d5ab33 117 /** Write to an I2C master.
be_bryan 0:b74591d5ab33 118 *
be_bryan 0:b74591d5ab33 119 * @param data pointer to the byte array to be transmitted
be_bryan 0:b74591d5ab33 120 * @param length the number of bytes to transmite
be_bryan 0:b74591d5ab33 121 *
be_bryan 0:b74591d5ab33 122 * @returns
be_bryan 0:b74591d5ab33 123 * 0 on success,
be_bryan 0:b74591d5ab33 124 * non-0 otherwise
be_bryan 0:b74591d5ab33 125 */
be_bryan 0:b74591d5ab33 126 int write(const char *data, int length);
be_bryan 0:b74591d5ab33 127
be_bryan 0:b74591d5ab33 128 /** Write a single byte to an I2C master.
be_bryan 0:b74591d5ab33 129 *
be_bryan 0:b74591d5ab33 130 * @param data the byte to write
be_bryan 0:b74591d5ab33 131 *
be_bryan 0:b74591d5ab33 132 * @returns
be_bryan 0:b74591d5ab33 133 * '1' if an ACK was received,
be_bryan 0:b74591d5ab33 134 * '0' otherwise
be_bryan 0:b74591d5ab33 135 */
be_bryan 0:b74591d5ab33 136 int write(int data);
be_bryan 0:b74591d5ab33 137
be_bryan 0:b74591d5ab33 138 /** Sets the I2C slave address.
be_bryan 0:b74591d5ab33 139 *
be_bryan 0:b74591d5ab33 140 * @param address The address to set for the slave (ignoring the least
be_bryan 0:b74591d5ab33 141 * signifcant bit). If set to 0, the slave will only respond to the
be_bryan 0:b74591d5ab33 142 * general call address.
be_bryan 0:b74591d5ab33 143 */
be_bryan 0:b74591d5ab33 144 void address(int address);
be_bryan 0:b74591d5ab33 145
be_bryan 0:b74591d5ab33 146 /** Reset the I2C slave back into the known ready receiving state.
be_bryan 0:b74591d5ab33 147 */
be_bryan 0:b74591d5ab33 148 void stop(void);
be_bryan 0:b74591d5ab33 149
be_bryan 0:b74591d5ab33 150 protected:
be_bryan 0:b74591d5ab33 151 i2c_t _i2c;
be_bryan 0:b74591d5ab33 152 };
be_bryan 0:b74591d5ab33 153
be_bryan 0:b74591d5ab33 154 } // namespace mbed
be_bryan 0:b74591d5ab33 155
be_bryan 0:b74591d5ab33 156 #endif
be_bryan 0:b74591d5ab33 157
be_bryan 0:b74591d5ab33 158 #endif