Bernhard Filzmaier / mbed-src

mbed library sources

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api/I2CSlave.h@13:0645d8841f51, 2013-08-05 (annotated)

Committer:
bogdanm
Date:
Mon Aug 05 14:12:34 2013 +0300
Revision:
13:0645d8841f51
Parent:
10:3bc89ef62ce7 
Update mbed sources to revision 64

Who changed what in which revision?

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bogdanm 13:0645d8841f51 1 /* mbed Microcontroller Library
bogdanm 13:0645d8841f51 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 13:0645d8841f51 3 *
bogdanm 13:0645d8841f51 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 13:0645d8841f51 5 * you may not use this file except in compliance with the License.
bogdanm 13:0645d8841f51 6 * You may obtain a copy of the License at
bogdanm 13:0645d8841f51 7 *
bogdanm 13:0645d8841f51 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 13:0645d8841f51 9 *
bogdanm 13:0645d8841f51 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 13:0645d8841f51 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 13:0645d8841f51 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 13:0645d8841f51 13 * See the License for the specific language governing permissions and
bogdanm 13:0645d8841f51 14 * limitations under the License.
bogdanm 13:0645d8841f51 15 */
bogdanm 13:0645d8841f51 16 #ifndef MBED_I2C_SLAVE_H
bogdanm 13:0645d8841f51 17 #define MBED_I2C_SLAVE_H
bogdanm 13:0645d8841f51 18
bogdanm 13:0645d8841f51 19 #include "platform.h"
bogdanm 13:0645d8841f51 20
bogdanm 13:0645d8841f51 21 #if DEVICE_I2CSLAVE
bogdanm 13:0645d8841f51 22
bogdanm 13:0645d8841f51 23 #include "i2c_api.h"
bogdanm 13:0645d8841f51 24
bogdanm 13:0645d8841f51 25 namespace mbed {
bogdanm 13:0645d8841f51 26
bogdanm 13:0645d8841f51 27 /** An I2C Slave, used for communicating with an I2C Master device
bogdanm 13:0645d8841f51 28 *
bogdanm 13:0645d8841f51 29 * Example:
bogdanm 13:0645d8841f51 30 * @code
bogdanm 13:0645d8841f51 31 * // Simple I2C responder
bogdanm 13:0645d8841f51 32 * #include <mbed.h>
bogdanm 13:0645d8841f51 33 *
bogdanm 13:0645d8841f51 34 * I2CSlave slave(p9, p10);
bogdanm 13:0645d8841f51 35 *
bogdanm 13:0645d8841f51 36 * int main() {
bogdanm 13:0645d8841f51 37 * char buf[10];
bogdanm 13:0645d8841f51 38 * char msg[] = "Slave!";
bogdanm 13:0645d8841f51 39 *
bogdanm 13:0645d8841f51 40 * slave.address(0xA0);
bogdanm 13:0645d8841f51 41 * while (1) {
bogdanm 13:0645d8841f51 42 * int i = slave.receive();
bogdanm 13:0645d8841f51 43 * switch (i) {
bogdanm 13:0645d8841f51 44 * case I2CSlave::ReadAddressed:
bogdanm 13:0645d8841f51 45 * slave.write(msg, strlen(msg) + 1); // Includes null char
bogdanm 13:0645d8841f51 46 * break;
bogdanm 13:0645d8841f51 47 * case I2CSlave::WriteGeneral:
bogdanm 13:0645d8841f51 48 * slave.read(buf, 10);
bogdanm 13:0645d8841f51 49 * printf("Read G: %s\n", buf);
bogdanm 13:0645d8841f51 50 * break;
bogdanm 13:0645d8841f51 51 * case I2CSlave::WriteAddressed:
bogdanm 13:0645d8841f51 52 * slave.read(buf, 10);
bogdanm 13:0645d8841f51 53 * printf("Read A: %s\n", buf);
bogdanm 13:0645d8841f51 54 * break;
bogdanm 13:0645d8841f51 55 * }
bogdanm 13:0645d8841f51 56 * for(int i = 0; i < 10; i++) buf[i] = 0; // Clear buffer
bogdanm 13:0645d8841f51 57 * }
bogdanm 13:0645d8841f51 58 * }
bogdanm 13:0645d8841f51 59 * @endcode
bogdanm 13:0645d8841f51 60 */
bogdanm 13:0645d8841f51 61 class I2CSlave {
bogdanm 13:0645d8841f51 62
bogdanm 13:0645d8841f51 63 public:
bogdanm 13:0645d8841f51 64 enum RxStatus {
bogdanm 13:0645d8841f51 65 NoData = 0,
bogdanm 13:0645d8841f51 66 ReadAddressed = 1,
bogdanm 13:0645d8841f51 67 WriteGeneral = 2,
bogdanm 13:0645d8841f51 68 WriteAddressed = 3
bogdanm 13:0645d8841f51 69 };
bogdanm 13:0645d8841f51 70
bogdanm 13:0645d8841f51 71 /** Create an I2C Slave interface, connected to the specified pins.
bogdanm 13:0645d8841f51 72 *
bogdanm 13:0645d8841f51 73 * @param sda I2C data line pin
bogdanm 13:0645d8841f51 74 * @param scl I2C clock line pin
bogdanm 13:0645d8841f51 75 */
bogdanm 13:0645d8841f51 76 I2CSlave(PinName sda, PinName scl);
bogdanm 13:0645d8841f51 77
bogdanm 13:0645d8841f51 78 /** Set the frequency of the I2C interface
bogdanm 13:0645d8841f51 79 *
bogdanm 13:0645d8841f51 80 * @param hz The bus frequency in hertz
bogdanm 13:0645d8841f51 81 */
bogdanm 13:0645d8841f51 82 void frequency(int hz);
bogdanm 13:0645d8841f51 83
bogdanm 13:0645d8841f51 84 /** Checks to see if this I2C Slave has been addressed.
bogdanm 13:0645d8841f51 85 *
bogdanm 13:0645d8841f51 86 * @returns
bogdanm 13:0645d8841f51 87 * A status indicating if the device has been addressed, and how
bogdanm 13:0645d8841f51 88 * - NoData - the slave has not been addressed
bogdanm 13:0645d8841f51 89 * - ReadAddressed - the master has requested a read from this slave
bogdanm 13:0645d8841f51 90 * - WriteAddressed - the master is writing to this slave
bogdanm 13:0645d8841f51 91 * - WriteGeneral - the master is writing to all slave
bogdanm 13:0645d8841f51 92 */
bogdanm 13:0645d8841f51 93 int receive(void);
bogdanm 13:0645d8841f51 94
bogdanm 13:0645d8841f51 95 /** Read from an I2C master.
bogdanm 13:0645d8841f51 96 *
bogdanm 13:0645d8841f51 97 * @param data pointer to the byte array to read data in to
bogdanm 13:0645d8841f51 98 * @param length maximum number of bytes to read
bogdanm 13:0645d8841f51 99 *
bogdanm 13:0645d8841f51 100 * @returns
bogdanm 13:0645d8841f51 101 * 0 on success,
bogdanm 13:0645d8841f51 102 * non-0 otherwise
bogdanm 13:0645d8841f51 103 */
bogdanm 13:0645d8841f51 104 int read(char *data, int length);
bogdanm 13:0645d8841f51 105
bogdanm 13:0645d8841f51 106 /** Read a single byte from an I2C master.
bogdanm 13:0645d8841f51 107 *
bogdanm 13:0645d8841f51 108 * @returns
bogdanm 13:0645d8841f51 109 * the byte read
bogdanm 13:0645d8841f51 110 */
bogdanm 13:0645d8841f51 111 int read(void);
bogdanm 13:0645d8841f51 112
bogdanm 13:0645d8841f51 113 /** Write to an I2C master.
bogdanm 13:0645d8841f51 114 *
bogdanm 13:0645d8841f51 115 * @param data pointer to the byte array to be transmitted
bogdanm 13:0645d8841f51 116 * @param length the number of bytes to transmite
bogdanm 13:0645d8841f51 117 *
bogdanm 13:0645d8841f51 118 * @returns
bogdanm 13:0645d8841f51 119 * 0 on success,
bogdanm 13:0645d8841f51 120 * non-0 otherwise
bogdanm 13:0645d8841f51 121 */
bogdanm 13:0645d8841f51 122 int write(const char *data, int length);
bogdanm 13:0645d8841f51 123
bogdanm 13:0645d8841f51 124 /** Write a single byte to an I2C master.
bogdanm 13:0645d8841f51 125 *
bogdanm 13:0645d8841f51 126 * @data the byte to write
bogdanm 13:0645d8841f51 127 *
bogdanm 13:0645d8841f51 128 * @returns
bogdanm 13:0645d8841f51 129 * '1' if an ACK was received,
bogdanm 13:0645d8841f51 130 * '0' otherwise
bogdanm 13:0645d8841f51 131 */
bogdanm 13:0645d8841f51 132 int write(int data);
bogdanm 13:0645d8841f51 133
bogdanm 13:0645d8841f51 134 /** Sets the I2C slave address.
bogdanm 13:0645d8841f51 135 *
bogdanm 13:0645d8841f51 136 * @param address The address to set for the slave (ignoring the least
bogdanm 13:0645d8841f51 137 * signifcant bit). If set to 0, the slave will only respond to the
bogdanm 13:0645d8841f51 138 * general call address.
bogdanm 13:0645d8841f51 139 */
bogdanm 13:0645d8841f51 140 void address(int address);
bogdanm 13:0645d8841f51 141
bogdanm 13:0645d8841f51 142 /** Reset the I2C slave back into the known ready receiving state.
bogdanm 13:0645d8841f51 143 */
bogdanm 13:0645d8841f51 144 void stop(void);
bogdanm 13:0645d8841f51 145
bogdanm 13:0645d8841f51 146 protected:
bogdanm 13:0645d8841f51 147 i2c_t _i2c;
bogdanm 13:0645d8841f51 148 };
bogdanm 13:0645d8841f51 149
bogdanm 13:0645d8841f51 150 } // namespace mbed
bogdanm 13:0645d8841f51 151
bogdanm 13:0645d8841f51 152 #endif
bogdanm 13:0645d8841f51 153
bogdanm 13:0645d8841f51 154 #endif