Ricardo Benitez / mbed

meh

Fork of mbed by mbed official

I2CSlave.h@118:16969dd821af, 2016-04-05 (annotated)

Committer:
ricardobtez
Date:
Tue Apr 05 23:51:21 2016 +0000
Revision:
118:16969dd821af
Parent:
65:5798e58a58b1 
dgdgr

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 65:5798e58a58b1 1 /* mbed Microcontroller Library
bogdanm 65:5798e58a58b1 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 65:5798e58a58b1 3 *
bogdanm 65:5798e58a58b1 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 65:5798e58a58b1 5 * you may not use this file except in compliance with the License.
bogdanm 65:5798e58a58b1 6 * You may obtain a copy of the License at
bogdanm 65:5798e58a58b1 7 *
bogdanm 65:5798e58a58b1 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 65:5798e58a58b1 9 *
bogdanm 65:5798e58a58b1 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 65:5798e58a58b1 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 65:5798e58a58b1 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 65:5798e58a58b1 13 * See the License for the specific language governing permissions and
bogdanm 65:5798e58a58b1 14 * limitations under the License.
bogdanm 65:5798e58a58b1 15 */
bogdanm 65:5798e58a58b1 16 #ifndef MBED_I2C_SLAVE_H
bogdanm 65:5798e58a58b1 17 #define MBED_I2C_SLAVE_H
bogdanm 65:5798e58a58b1 18
bogdanm 65:5798e58a58b1 19 #include "platform.h"
bogdanm 65:5798e58a58b1 20
bogdanm 65:5798e58a58b1 21 #if DEVICE_I2CSLAVE
bogdanm 65:5798e58a58b1 22
bogdanm 65:5798e58a58b1 23 #include "i2c_api.h"
bogdanm 65:5798e58a58b1 24
bogdanm 65:5798e58a58b1 25 namespace mbed {
bogdanm 65:5798e58a58b1 26
bogdanm 65:5798e58a58b1 27 /** An I2C Slave, used for communicating with an I2C Master device
bogdanm 65:5798e58a58b1 28 *
bogdanm 65:5798e58a58b1 29 * Example:
bogdanm 65:5798e58a58b1 30 * @code
bogdanm 65:5798e58a58b1 31 * // Simple I2C responder
bogdanm 65:5798e58a58b1 32 * #include <mbed.h>
bogdanm 65:5798e58a58b1 33 *
bogdanm 65:5798e58a58b1 34 * I2CSlave slave(p9, p10);
bogdanm 65:5798e58a58b1 35 *
bogdanm 65:5798e58a58b1 36 * int main() {
bogdanm 65:5798e58a58b1 37 * char buf[10];
bogdanm 65:5798e58a58b1 38 * char msg[] = "Slave!";
bogdanm 65:5798e58a58b1 39 *
bogdanm 65:5798e58a58b1 40 * slave.address(0xA0);
bogdanm 65:5798e58a58b1 41 * while (1) {
bogdanm 65:5798e58a58b1 42 * int i = slave.receive();
bogdanm 65:5798e58a58b1 43 * switch (i) {
bogdanm 65:5798e58a58b1 44 * case I2CSlave::ReadAddressed:
bogdanm 65:5798e58a58b1 45 * slave.write(msg, strlen(msg) + 1); // Includes null char
bogdanm 65:5798e58a58b1 46 * break;
bogdanm 65:5798e58a58b1 47 * case I2CSlave::WriteGeneral:
bogdanm 65:5798e58a58b1 48 * slave.read(buf, 10);
bogdanm 65:5798e58a58b1 49 * printf("Read G: %s\n", buf);
bogdanm 65:5798e58a58b1 50 * break;
bogdanm 65:5798e58a58b1 51 * case I2CSlave::WriteAddressed:
bogdanm 65:5798e58a58b1 52 * slave.read(buf, 10);
bogdanm 65:5798e58a58b1 53 * printf("Read A: %s\n", buf);
bogdanm 65:5798e58a58b1 54 * break;
bogdanm 65:5798e58a58b1 55 * }
bogdanm 65:5798e58a58b1 56 * for(int i = 0; i < 10; i++) buf[i] = 0; // Clear buffer
bogdanm 65:5798e58a58b1 57 * }
bogdanm 65:5798e58a58b1 58 * }
bogdanm 65:5798e58a58b1 59 * @endcode
bogdanm 65:5798e58a58b1 60 */
bogdanm 65:5798e58a58b1 61 class I2CSlave {
bogdanm 65:5798e58a58b1 62
bogdanm 65:5798e58a58b1 63 public:
bogdanm 65:5798e58a58b1 64 enum RxStatus {
bogdanm 65:5798e58a58b1 65 NoData = 0,
bogdanm 65:5798e58a58b1 66 ReadAddressed = 1,
bogdanm 65:5798e58a58b1 67 WriteGeneral = 2,
bogdanm 65:5798e58a58b1 68 WriteAddressed = 3
bogdanm 65:5798e58a58b1 69 };
bogdanm 65:5798e58a58b1 70
bogdanm 65:5798e58a58b1 71 /** Create an I2C Slave interface, connected to the specified pins.
bogdanm 65:5798e58a58b1 72 *
bogdanm 65:5798e58a58b1 73 * @param sda I2C data line pin
bogdanm 65:5798e58a58b1 74 * @param scl I2C clock line pin
bogdanm 65:5798e58a58b1 75 */
bogdanm 65:5798e58a58b1 76 I2CSlave(PinName sda, PinName scl);
bogdanm 65:5798e58a58b1 77
bogdanm 65:5798e58a58b1 78 /** Set the frequency of the I2C interface
bogdanm 65:5798e58a58b1 79 *
bogdanm 65:5798e58a58b1 80 * @param hz The bus frequency in hertz
bogdanm 65:5798e58a58b1 81 */
bogdanm 65:5798e58a58b1 82 void frequency(int hz);
bogdanm 65:5798e58a58b1 83
bogdanm 65:5798e58a58b1 84 /** Checks to see if this I2C Slave has been addressed.
bogdanm 65:5798e58a58b1 85 *
bogdanm 65:5798e58a58b1 86 * @returns
bogdanm 65:5798e58a58b1 87 * A status indicating if the device has been addressed, and how
bogdanm 65:5798e58a58b1 88 * - NoData - the slave has not been addressed
bogdanm 65:5798e58a58b1 89 * - ReadAddressed - the master has requested a read from this slave
bogdanm 65:5798e58a58b1 90 * - WriteAddressed - the master is writing to this slave
bogdanm 65:5798e58a58b1 91 * - WriteGeneral - the master is writing to all slave
bogdanm 65:5798e58a58b1 92 */
bogdanm 65:5798e58a58b1 93 int receive(void);
bogdanm 65:5798e58a58b1 94
bogdanm 65:5798e58a58b1 95 /** Read from an I2C master.
bogdanm 65:5798e58a58b1 96 *
bogdanm 65:5798e58a58b1 97 * @param data pointer to the byte array to read data in to
bogdanm 65:5798e58a58b1 98 * @param length maximum number of bytes to read
bogdanm 65:5798e58a58b1 99 *
bogdanm 65:5798e58a58b1 100 * @returns
bogdanm 65:5798e58a58b1 101 * 0 on success,
bogdanm 65:5798e58a58b1 102 * non-0 otherwise
bogdanm 65:5798e58a58b1 103 */
bogdanm 65:5798e58a58b1 104 int read(char *data, int length);
bogdanm 65:5798e58a58b1 105
bogdanm 65:5798e58a58b1 106 /** Read a single byte from an I2C master.
bogdanm 65:5798e58a58b1 107 *
bogdanm 65:5798e58a58b1 108 * @returns
bogdanm 65:5798e58a58b1 109 * the byte read
bogdanm 65:5798e58a58b1 110 */
bogdanm 65:5798e58a58b1 111 int read(void);
bogdanm 65:5798e58a58b1 112
bogdanm 65:5798e58a58b1 113 /** Write to an I2C master.
bogdanm 65:5798e58a58b1 114 *
bogdanm 65:5798e58a58b1 115 * @param data pointer to the byte array to be transmitted
bogdanm 65:5798e58a58b1 116 * @param length the number of bytes to transmite
bogdanm 65:5798e58a58b1 117 *
bogdanm 65:5798e58a58b1 118 * @returns
bogdanm 65:5798e58a58b1 119 * 0 on success,
bogdanm 65:5798e58a58b1 120 * non-0 otherwise
bogdanm 65:5798e58a58b1 121 */
bogdanm 65:5798e58a58b1 122 int write(const char *data, int length);
bogdanm 65:5798e58a58b1 123
bogdanm 65:5798e58a58b1 124 /** Write a single byte to an I2C master.
bogdanm 65:5798e58a58b1 125 *
bogdanm 65:5798e58a58b1 126 * @data the byte to write
bogdanm 65:5798e58a58b1 127 *
bogdanm 65:5798e58a58b1 128 * @returns
bogdanm 65:5798e58a58b1 129 * '1' if an ACK was received,
bogdanm 65:5798e58a58b1 130 * '0' otherwise
bogdanm 65:5798e58a58b1 131 */
bogdanm 65:5798e58a58b1 132 int write(int data);
bogdanm 65:5798e58a58b1 133
bogdanm 65:5798e58a58b1 134 /** Sets the I2C slave address.
bogdanm 65:5798e58a58b1 135 *
bogdanm 65:5798e58a58b1 136 * @param address The address to set for the slave (ignoring the least
bogdanm 65:5798e58a58b1 137 * signifcant bit). If set to 0, the slave will only respond to the
bogdanm 65:5798e58a58b1 138 * general call address.
bogdanm 65:5798e58a58b1 139 */
bogdanm 65:5798e58a58b1 140 void address(int address);
bogdanm 65:5798e58a58b1 141
bogdanm 65:5798e58a58b1 142 /** Reset the I2C slave back into the known ready receiving state.
bogdanm 65:5798e58a58b1 143 */
bogdanm 65:5798e58a58b1 144 void stop(void);
bogdanm 65:5798e58a58b1 145
bogdanm 65:5798e58a58b1 146 protected:
bogdanm 65:5798e58a58b1 147 i2c_t _i2c;
bogdanm 65:5798e58a58b1 148 };
bogdanm 65:5798e58a58b1 149
bogdanm 65:5798e58a58b1 150 } // namespace mbed
bogdanm 65:5798e58a58b1 151
bogdanm 65:5798e58a58b1 152 #endif
bogdanm 65:5798e58a58b1 153
bogdanm 65:5798e58a58b1 154 #endif