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I2CSlave.h@43:e2ed12d17f06, 2012-10-26 (annotated)

Committer:
emilmont
Date:
Fri Oct 26 17:40:46 2012 +0100
Revision:
43:e2ed12d17f06
Parent:
27:7110ebee3484
Child:
44:24d45a770a51
Update documentation

Who changed what in which revision?

UserRevisionLine numberNew contents of line
simon 22:9114680c05da 1 /* mbed Microcontroller Library - I2CSlave
emilmont 27:7110ebee3484 2 * Copyright (c) 2007-2011 ARM Limited. All rights reserved.
simon 22:9114680c05da 3 */
simon 22:9114680c05da 4
simon 22:9114680c05da 5 #ifndef MBED_I2C_SLAVE_H
simon 22:9114680c05da 6 #define MBED_I2C_SLAVE_H
simon 22:9114680c05da 7
emilmont 27:7110ebee3484 8 #include "device.h"
emilmont 27:7110ebee3484 9
emilmont 27:7110ebee3484 10 #if DEVICE_I2CSLAVE
emilmont 27:7110ebee3484 11
simon 22:9114680c05da 12 #include "platform.h"
simon 22:9114680c05da 13 #include "PinNames.h"
simon 22:9114680c05da 14 #include "PeripheralNames.h"
simon 22:9114680c05da 15 #include "Base.h"
simon 22:9114680c05da 16
simon 22:9114680c05da 17 namespace mbed {
simon 22:9114680c05da 18
emilmont 43:e2ed12d17f06 19 /** An I2C Slave, used for communicating with an I2C Master device
simon 22:9114680c05da 20 *
simon 22:9114680c05da 21 * Example:
emilmont 43:e2ed12d17f06 22 * @code
emilmont 43:e2ed12d17f06 23 * // Simple I2C responder
emilmont 43:e2ed12d17f06 24 * #include <mbed.h>
emilmont 43:e2ed12d17f06 25 *
emilmont 43:e2ed12d17f06 26 * I2CSlave slave(p9, p10);
emilmont 43:e2ed12d17f06 27 *
emilmont 43:e2ed12d17f06 28 * int main() {
emilmont 43:e2ed12d17f06 29 * char buf[10];
emilmont 43:e2ed12d17f06 30 * char msg[] = "Slave!";
emilmont 43:e2ed12d17f06 31 *
emilmont 43:e2ed12d17f06 32 * slave.address(0xA0);
emilmont 43:e2ed12d17f06 33 * while (1) {
emilmont 43:e2ed12d17f06 34 * int i = slave.receive();
emilmont 43:e2ed12d17f06 35 * switch (i) {
emilmont 43:e2ed12d17f06 36 * case I2CSlave::ReadAddressed:
emilmont 43:e2ed12d17f06 37 * slave.write(msg, strlen(msg) + 1); // Includes null char
emilmont 43:e2ed12d17f06 38 * break;
emilmont 43:e2ed12d17f06 39 * case I2CSlave::WriteGeneral:
emilmont 43:e2ed12d17f06 40 * slave.read(buf, 10);
emilmont 43:e2ed12d17f06 41 * printf("Read G: %s\n", buf);
emilmont 43:e2ed12d17f06 42 * break;
emilmont 43:e2ed12d17f06 43 * case I2CSlave::WriteAddressed:
emilmont 43:e2ed12d17f06 44 * slave.read(buf, 10);
emilmont 43:e2ed12d17f06 45 * printf("Read A: %s\n", buf);
emilmont 43:e2ed12d17f06 46 * break;
emilmont 43:e2ed12d17f06 47 * }
emilmont 43:e2ed12d17f06 48 * for(int i = 0; i < 10; i++) buf[i] = 0; // Clear buffer
emilmont 43:e2ed12d17f06 49 * }
emilmont 43:e2ed12d17f06 50 * }
emilmont 43:e2ed12d17f06 51 * @endcode
simon 22:9114680c05da 52 */
simon 22:9114680c05da 53 class I2CSlave : public Base {
simon 22:9114680c05da 54
simon 22:9114680c05da 55 public:
simon 22:9114680c05da 56
simon 22:9114680c05da 57 enum RxStatus {
simon 22:9114680c05da 58 NoData = 0
simon 22:9114680c05da 59 , ReadAddressed = 1
simon 22:9114680c05da 60 , WriteGeneral = 2
simon 22:9114680c05da 61 , WriteAddressed = 3
simon 22:9114680c05da 62 };
simon 22:9114680c05da 63
emilmont 43:e2ed12d17f06 64 /** Create an I2C Slave interface, connected to the specified pins.
simon 22:9114680c05da 65 *
emilmont 43:e2ed12d17f06 66 * @param sda I2C data line pin
emilmont 43:e2ed12d17f06 67 * @param scl I2C clock line pin
simon 22:9114680c05da 68 */
simon 22:9114680c05da 69 I2CSlave(PinName sda, PinName scl, const char *name = NULL);
simon 22:9114680c05da 70
emilmont 43:e2ed12d17f06 71 /** Set the frequency of the I2C interface
simon 22:9114680c05da 72 *
emilmont 43:e2ed12d17f06 73 * @param hz The bus frequency in hertz
simon 22:9114680c05da 74 */
simon 22:9114680c05da 75 void frequency(int hz);
simon 22:9114680c05da 76
emilmont 43:e2ed12d17f06 77 /** Checks to see if this I2C Slave has been addressed.
simon 22:9114680c05da 78 *
emilmont 43:e2ed12d17f06 79 * @returns
emilmont 43:e2ed12d17f06 80 * A status indicating if the device has been addressed, and how
emilmont 43:e2ed12d17f06 81 * - NoData - the slave has not been addressed
emilmont 43:e2ed12d17f06 82 * - ReadAddressed - the master has requested a read from this slave
emilmont 43:e2ed12d17f06 83 * - WriteAddressed - the master is writing to this slave
emilmont 43:e2ed12d17f06 84 * - WriteGeneral - the master is writing to all slave
simon 22:9114680c05da 85 */
simon 22:9114680c05da 86 int receive(void);
simon 22:9114680c05da 87
emilmont 43:e2ed12d17f06 88 /** Read from an I2C master.
simon 22:9114680c05da 89 *
emilmont 43:e2ed12d17f06 90 * @param data pointer to the byte array to read data in to
emilmont 43:e2ed12d17f06 91 * @param length maximum number of bytes to read
emilmont 43:e2ed12d17f06 92 *
emilmont 43:e2ed12d17f06 93 * @returns
emilmont 43:e2ed12d17f06 94 * 0 on success,
emilmont 43:e2ed12d17f06 95 * non-0 otherwise
simon 22:9114680c05da 96 */
simon 22:9114680c05da 97 int read(char *data, int length);
simon 22:9114680c05da 98
emilmont 43:e2ed12d17f06 99 /** Read a single byte from an I2C master.
simon 22:9114680c05da 100 *
emilmont 43:e2ed12d17f06 101 * @returns
emilmont 43:e2ed12d17f06 102 * the byte read
simon 22:9114680c05da 103 */
simon 22:9114680c05da 104 int read(void);
simon 22:9114680c05da 105
emilmont 43:e2ed12d17f06 106 /** Write to an I2C master.
simon 22:9114680c05da 107 *
emilmont 43:e2ed12d17f06 108 * @param data pointer to the byte array to be transmitted
emilmont 43:e2ed12d17f06 109 * @param length the number of bytes to transmite
emilmont 43:e2ed12d17f06 110 *
emilmont 43:e2ed12d17f06 111 * @returns
emilmont 43:e2ed12d17f06 112 * 0 on success,
emilmont 43:e2ed12d17f06 113 * non-0 otherwise
simon 22:9114680c05da 114 */
simon 22:9114680c05da 115 int write(const char *data, int length);
simon 22:9114680c05da 116
emilmont 43:e2ed12d17f06 117 /** Write a single byte to an I2C master.
emilmont 43:e2ed12d17f06 118 *
emilmont 43:e2ed12d17f06 119 * @data the byte to write
simon 22:9114680c05da 120 *
emilmont 43:e2ed12d17f06 121 * @returns
emilmont 43:e2ed12d17f06 122 * '1' if an ACK was received,
emilmont 43:e2ed12d17f06 123 * '0' otherwise
simon 22:9114680c05da 124 */
simon 22:9114680c05da 125 int write(int data);
simon 22:9114680c05da 126
emilmont 43:e2ed12d17f06 127 /** Sets the I2C slave address.
simon 22:9114680c05da 128 *
emilmont 43:e2ed12d17f06 129 * @param address The address to set for the slave (ignoring the least
emilmont 43:e2ed12d17f06 130 * signifcant bit). If set to 0, the slave will only respond to the
emilmont 43:e2ed12d17f06 131 * general call address.
simon 22:9114680c05da 132 */
simon 22:9114680c05da 133 void address(int address);
simon 22:9114680c05da 134
emilmont 43:e2ed12d17f06 135 /** Reset the I2C slave back into the known ready receiving state.
simon 22:9114680c05da 136 */
simon 22:9114680c05da 137 void stop(void);
simon 22:9114680c05da 138
simon 22:9114680c05da 139 protected:
simon 22:9114680c05da 140
simon 22:9114680c05da 141 I2CName _i2c;
simon 22:9114680c05da 142 };
simon 22:9114680c05da 143
simon 22:9114680c05da 144 } // namespace mbed
simon 22:9114680c05da 145
simon 22:9114680c05da 146 #endif
emilmont 27:7110ebee3484 147
emilmont 27:7110ebee3484 148 #endif
emilmont 27:7110ebee3484 149