Sertel_Srinath Gopalan / USB_SERTEL_LOG

Soundharrajan

Fork of mbed by mbed official

I2CSlave.h@92:f7fcbaa5f1b5, 2016-06-12 (annotated)

Committer:
mrsoundhar
Date:
Sun Jun 12 16:45:04 2016 +0000
Revision:
92:f7fcbaa5f1b5
Parent:
27:7110ebee3484
Child:
43:e2ed12d17f06
Soundharrajan

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
simon 22:9114680c05da 19 /* Class: I2CSlave
simon 22:9114680c05da 20 * An I2C Slave, used for communicating with an I2C Master device
simon 22:9114680c05da 21 *
simon 22:9114680c05da 22 * Example:
simon 22:9114680c05da 23 * > // Simple I2C responder
simon 22:9114680c05da 24 * > #include <mbed.h>
simon 22:9114680c05da 25 * >
simon 22:9114680c05da 26 * > I2CSlave slave(p9, p10);
simon 22:9114680c05da 27 * >
simon 22:9114680c05da 28 * > int main() {
simon 22:9114680c05da 29 * > char buf[10];
simon 22:9114680c05da 30 * > char msg[] = "Slave!";
simon 22:9114680c05da 31 * >
simon 22:9114680c05da 32 * > slave.address(0xA0);
simon 22:9114680c05da 33 * > while (1) {
simon 22:9114680c05da 34 * > int i = slave.receive();
simon 22:9114680c05da 35 * > switch (i) {
simon 22:9114680c05da 36 * > case I2CSlave::ReadAddressed:
simon 22:9114680c05da 37 * > slave.write(msg, strlen(msg) + 1); // Includes null char
simon 22:9114680c05da 38 * > break;
simon 22:9114680c05da 39 * > case I2CSlave::WriteGeneral:
simon 22:9114680c05da 40 * > slave.read(buf, 10);
simon 22:9114680c05da 41 * > printf("Read G: %s\n", buf);
simon 22:9114680c05da 42 * > break;
simon 22:9114680c05da 43 * > case I2CSlave::WriteAddressed:
simon 22:9114680c05da 44 * > slave.read(buf, 10);
simon 22:9114680c05da 45 * > printf("Read A: %s\n", buf);
simon 22:9114680c05da 46 * > break;
simon 22:9114680c05da 47 * > }
simon 22:9114680c05da 48 * > for(int i = 0; i < 10; i++) buf[i] = 0; // Clear buffer
simon 22:9114680c05da 49 * > }
simon 22:9114680c05da 50 * > }
simon 22:9114680c05da 51 * >
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
simon 22:9114680c05da 64 /* Constructor: I2CSlave
simon 22:9114680c05da 65 * Create an I2C Slave interface, connected to the specified pins.
simon 22:9114680c05da 66 *
simon 22:9114680c05da 67 * Variables:
simon 22:9114680c05da 68 * sda - I2C data line pin
simon 22:9114680c05da 69 * scl - I2C clock line pin
simon 22:9114680c05da 70 */
simon 22:9114680c05da 71 I2CSlave(PinName sda, PinName scl, const char *name = NULL);
simon 22:9114680c05da 72
simon 22:9114680c05da 73 /* Function: frequency
simon 22:9114680c05da 74 * Set the frequency of the I2C interface
simon 22:9114680c05da 75 *
simon 22:9114680c05da 76 * Variables:
simon 22:9114680c05da 77 * hz - The bus frequency in hertz
simon 22:9114680c05da 78 */
simon 22:9114680c05da 79 void frequency(int hz);
simon 22:9114680c05da 80
simon 22:9114680c05da 81 /* Function: receive
simon 22:9114680c05da 82 * Checks to see if this I2C Slave has been addressed.
simon 22:9114680c05da 83 *
simon 22:9114680c05da 84 * Variables:
simon 22:9114680c05da 85 * returns - a status indicating if the device has been addressed, and how
simon 22:9114680c05da 86 * > NoData - the slave has not been addressed
simon 22:9114680c05da 87 * > ReadAddressed - the master has requested a read from this slave
simon 22:9114680c05da 88 * > WriteAddressed - the master is writing to this slave
simon 22:9114680c05da 89 * > WriteGeneral - the master is writing to all slave
simon 22:9114680c05da 90 */
simon 22:9114680c05da 91 int receive(void);
simon 22:9114680c05da 92
simon 22:9114680c05da 93 /* Function: read
simon 22:9114680c05da 94 * Read from an I2C master.
simon 22:9114680c05da 95 *
simon 22:9114680c05da 96 * Variables:
simon 22:9114680c05da 97 * data - pointer to the byte array to read data in to
simon 22:9114680c05da 98 * length - maximum number of bytes to read
simon 22:9114680c05da 99 * returns - 0 on success, non-0 otherwise
simon 22:9114680c05da 100 */
simon 22:9114680c05da 101 int read(char *data, int length);
simon 22:9114680c05da 102
simon 22:9114680c05da 103 /* Function: read
simon 22:9114680c05da 104 * Read a single byte from an I2C master.
simon 22:9114680c05da 105 *
simon 22:9114680c05da 106 * Variables:
simon 22:9114680c05da 107 * returns - the byte read
simon 22:9114680c05da 108 */
simon 22:9114680c05da 109 int read(void);
simon 22:9114680c05da 110
simon 22:9114680c05da 111 /* Function: write
simon 22:9114680c05da 112 * Write to an I2C master.
simon 22:9114680c05da 113 *
simon 22:9114680c05da 114 * Variables:
simon 22:9114680c05da 115 * data - pointer to the byte array to be transmitted
simon 22:9114680c05da 116 * length - the number of bytes to transmite
simon 22:9114680c05da 117 * returns - a 0 on success, non-0 otherwise
simon 22:9114680c05da 118 */
simon 22:9114680c05da 119 int write(const char *data, int length);
simon 22:9114680c05da 120
simon 22:9114680c05da 121 /* Function: write
simon 22:9114680c05da 122 * Write a single byte to an I2C master.
simon 22:9114680c05da 123 *
simon 22:9114680c05da 124 * Variables
simon 22:9114680c05da 125 * data - the byte to write
simon 22:9114680c05da 126 * returns - a '1' if an ACK was received, a '0' otherwise
simon 22:9114680c05da 127 */
simon 22:9114680c05da 128 int write(int data);
simon 22:9114680c05da 129
simon 22:9114680c05da 130 /* Function: address
simon 22:9114680c05da 131 * Sets the I2C slave address.
simon 22:9114680c05da 132 *
simon 22:9114680c05da 133 * Variables
simon 22:9114680c05da 134 * address - the address to set for the slave (ignoring the least
simon 22:9114680c05da 135 * signifcant bit). If set to 0, the slave will only respond to the
simon 22:9114680c05da 136 * general call address.
simon 22:9114680c05da 137 */
simon 22:9114680c05da 138 void address(int address);
simon 22:9114680c05da 139
simon 22:9114680c05da 140 /* Function: stop
simon 22:9114680c05da 141 * Reset the I2C slave back into the known ready receiving state.
simon 22:9114680c05da 142 */
simon 22:9114680c05da 143 void stop(void);
simon 22:9114680c05da 144
simon 22:9114680c05da 145 protected:
simon 22:9114680c05da 146
simon 22:9114680c05da 147 I2CName _i2c;
simon 22:9114680c05da 148 };
simon 22:9114680c05da 149
simon 22:9114680c05da 150 } // namespace mbed
simon 22:9114680c05da 151
simon 22:9114680c05da 152 #endif
emilmont 27:7110ebee3484 153
emilmont 27:7110ebee3484 154 #endif
emilmont 27:7110ebee3484 155