Aravind Vadali / mbed-src-AV

mbed.h library with any bug fixes AV finds.

Dependents:   micromouse4_encoder_testing PID_Test Lab1_Test WorkingPID ... more

api/I2C.h@0:ba7650f404af, 2015-11-02 (annotated)

Committer:
aravindsv
Date:
Mon Nov 02 02:26:59 2015 +0000
Revision:
0:ba7650f404af
Reduced HSE_STARTUP_TIMEOUT to 500 ms, fixed some compiler warnings

Who changed what in which revision?

UserRevisionLine numberNew contents of line
aravindsv 0:ba7650f404af 1 /* mbed Microcontroller Library
aravindsv 0:ba7650f404af 2 * Copyright (c) 2006-2015 ARM Limited
aravindsv 0:ba7650f404af 3 *
aravindsv 0:ba7650f404af 4 * Licensed under the Apache License, Version 2.0 (the "License");
aravindsv 0:ba7650f404af 5 * you may not use this file except in compliance with the License.
aravindsv 0:ba7650f404af 6 * You may obtain a copy of the License at
aravindsv 0:ba7650f404af 7 *
aravindsv 0:ba7650f404af 8 * http://www.apache.org/licenses/LICENSE-2.0
aravindsv 0:ba7650f404af 9 *
aravindsv 0:ba7650f404af 10 * Unless required by applicable law or agreed to in writing, software
aravindsv 0:ba7650f404af 11 * distributed under the License is distributed on an "AS IS" BASIS,
aravindsv 0:ba7650f404af 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
aravindsv 0:ba7650f404af 13 * See the License for the specific language governing permissions and
aravindsv 0:ba7650f404af 14 * limitations under the License.
aravindsv 0:ba7650f404af 15 */
aravindsv 0:ba7650f404af 16 #ifndef MBED_I2C_H
aravindsv 0:ba7650f404af 17 #define MBED_I2C_H
aravindsv 0:ba7650f404af 18
aravindsv 0:ba7650f404af 19 #include "platform.h"
aravindsv 0:ba7650f404af 20
aravindsv 0:ba7650f404af 21 #if DEVICE_I2C
aravindsv 0:ba7650f404af 22
aravindsv 0:ba7650f404af 23 #include "i2c_api.h"
aravindsv 0:ba7650f404af 24
aravindsv 0:ba7650f404af 25 #if DEVICE_I2C_ASYNCH
aravindsv 0:ba7650f404af 26 #include "CThunk.h"
aravindsv 0:ba7650f404af 27 #include "dma_api.h"
aravindsv 0:ba7650f404af 28 #include "FunctionPointer.h"
aravindsv 0:ba7650f404af 29 #endif
aravindsv 0:ba7650f404af 30
aravindsv 0:ba7650f404af 31 namespace mbed {
aravindsv 0:ba7650f404af 32
aravindsv 0:ba7650f404af 33 /** An I2C Master, used for communicating with I2C slave devices
aravindsv 0:ba7650f404af 34 *
aravindsv 0:ba7650f404af 35 * Example:
aravindsv 0:ba7650f404af 36 * @code
aravindsv 0:ba7650f404af 37 * // Read from I2C slave at address 0x62
aravindsv 0:ba7650f404af 38 *
aravindsv 0:ba7650f404af 39 * #include "mbed.h"
aravindsv 0:ba7650f404af 40 *
aravindsv 0:ba7650f404af 41 * I2C i2c(p28, p27);
aravindsv 0:ba7650f404af 42 *
aravindsv 0:ba7650f404af 43 * int main() {
aravindsv 0:ba7650f404af 44 * int address = 0x62;
aravindsv 0:ba7650f404af 45 * char data[2];
aravindsv 0:ba7650f404af 46 * i2c.read(address, data, 2);
aravindsv 0:ba7650f404af 47 * }
aravindsv 0:ba7650f404af 48 * @endcode
aravindsv 0:ba7650f404af 49 */
aravindsv 0:ba7650f404af 50 class I2C {
aravindsv 0:ba7650f404af 51
aravindsv 0:ba7650f404af 52 public:
aravindsv 0:ba7650f404af 53 enum RxStatus {
aravindsv 0:ba7650f404af 54 NoData,
aravindsv 0:ba7650f404af 55 MasterGeneralCall,
aravindsv 0:ba7650f404af 56 MasterWrite,
aravindsv 0:ba7650f404af 57 MasterRead
aravindsv 0:ba7650f404af 58 };
aravindsv 0:ba7650f404af 59
aravindsv 0:ba7650f404af 60 enum Acknowledge {
aravindsv 0:ba7650f404af 61 NoACK = 0,
aravindsv 0:ba7650f404af 62 ACK = 1
aravindsv 0:ba7650f404af 63 };
aravindsv 0:ba7650f404af 64
aravindsv 0:ba7650f404af 65 /** Create an I2C Master interface, connected to the specified pins
aravindsv 0:ba7650f404af 66 *
aravindsv 0:ba7650f404af 67 * @param sda I2C data line pin
aravindsv 0:ba7650f404af 68 * @param scl I2C clock line pin
aravindsv 0:ba7650f404af 69 */
aravindsv 0:ba7650f404af 70 I2C(PinName sda, PinName scl);
aravindsv 0:ba7650f404af 71
aravindsv 0:ba7650f404af 72 /** Set the frequency of the I2C interface
aravindsv 0:ba7650f404af 73 *
aravindsv 0:ba7650f404af 74 * @param hz The bus frequency in hertz
aravindsv 0:ba7650f404af 75 */
aravindsv 0:ba7650f404af 76 void frequency(int hz);
aravindsv 0:ba7650f404af 77
aravindsv 0:ba7650f404af 78 /** Read from an I2C slave
aravindsv 0:ba7650f404af 79 *
aravindsv 0:ba7650f404af 80 * Performs a complete read transaction. The bottom bit of
aravindsv 0:ba7650f404af 81 * the address is forced to 1 to indicate a read.
aravindsv 0:ba7650f404af 82 *
aravindsv 0:ba7650f404af 83 * @param address 8-bit I2C slave address [ addr | 1 ]
aravindsv 0:ba7650f404af 84 * @param data Pointer to the byte-array to read data in to
aravindsv 0:ba7650f404af 85 * @param length Number of bytes to read
aravindsv 0:ba7650f404af 86 * @param repeated Repeated start, true - don't send stop at end
aravindsv 0:ba7650f404af 87 *
aravindsv 0:ba7650f404af 88 * @returns
aravindsv 0:ba7650f404af 89 * 0 on success (ack),
aravindsv 0:ba7650f404af 90 * non-0 on failure (nack)
aravindsv 0:ba7650f404af 91 */
aravindsv 0:ba7650f404af 92 int read(int address, char *data, int length, bool repeated = false);
aravindsv 0:ba7650f404af 93
aravindsv 0:ba7650f404af 94 /** Read a single byte from the I2C bus
aravindsv 0:ba7650f404af 95 *
aravindsv 0:ba7650f404af 96 * @param ack indicates if the byte is to be acknowledged (1 = acknowledge)
aravindsv 0:ba7650f404af 97 *
aravindsv 0:ba7650f404af 98 * @returns
aravindsv 0:ba7650f404af 99 * the byte read
aravindsv 0:ba7650f404af 100 */
aravindsv 0:ba7650f404af 101 int read(int ack);
aravindsv 0:ba7650f404af 102
aravindsv 0:ba7650f404af 103 /** Write to an I2C slave
aravindsv 0:ba7650f404af 104 *
aravindsv 0:ba7650f404af 105 * Performs a complete write transaction. The bottom bit of
aravindsv 0:ba7650f404af 106 * the address is forced to 0 to indicate a write.
aravindsv 0:ba7650f404af 107 *
aravindsv 0:ba7650f404af 108 * @param address 8-bit I2C slave address [ addr | 0 ]
aravindsv 0:ba7650f404af 109 * @param data Pointer to the byte-array data to send
aravindsv 0:ba7650f404af 110 * @param length Number of bytes to send
aravindsv 0:ba7650f404af 111 * @param repeated Repeated start, true - do not send stop at end
aravindsv 0:ba7650f404af 112 *
aravindsv 0:ba7650f404af 113 * @returns
aravindsv 0:ba7650f404af 114 * 0 on success (ack),
aravindsv 0:ba7650f404af 115 * non-0 on failure (nack)
aravindsv 0:ba7650f404af 116 */
aravindsv 0:ba7650f404af 117 int write(int address, const char *data, int length, bool repeated = false);
aravindsv 0:ba7650f404af 118
aravindsv 0:ba7650f404af 119 /** Write single byte out on the I2C bus
aravindsv 0:ba7650f404af 120 *
aravindsv 0:ba7650f404af 121 * @param data data to write out on bus
aravindsv 0:ba7650f404af 122 *
aravindsv 0:ba7650f404af 123 * @returns
aravindsv 0:ba7650f404af 124 * '1' if an ACK was received,
aravindsv 0:ba7650f404af 125 * '0' otherwise
aravindsv 0:ba7650f404af 126 */
aravindsv 0:ba7650f404af 127 int write(int data);
aravindsv 0:ba7650f404af 128
aravindsv 0:ba7650f404af 129 /** Creates a start condition on the I2C bus
aravindsv 0:ba7650f404af 130 */
aravindsv 0:ba7650f404af 131
aravindsv 0:ba7650f404af 132 void start(void);
aravindsv 0:ba7650f404af 133
aravindsv 0:ba7650f404af 134 /** Creates a stop condition on the I2C bus
aravindsv 0:ba7650f404af 135 */
aravindsv 0:ba7650f404af 136 void stop(void);
aravindsv 0:ba7650f404af 137
aravindsv 0:ba7650f404af 138 #if DEVICE_I2C_ASYNCH
aravindsv 0:ba7650f404af 139
aravindsv 0:ba7650f404af 140 /** Start non-blocking I2C transfer.
aravindsv 0:ba7650f404af 141 *
aravindsv 0:ba7650f404af 142 * @param address 8/10 bit I2c slave address
aravindsv 0:ba7650f404af 143 * @param tx_buffer The TX buffer with data to be transfered
aravindsv 0:ba7650f404af 144 * @param tx_length The length of TX buffer in bytes
aravindsv 0:ba7650f404af 145 * @param rx_buffer The RX buffer which is used for received data
aravindsv 0:ba7650f404af 146 * @param rx_length The length of RX buffer in bytes
aravindsv 0:ba7650f404af 147 * @param event The logical OR of events to modify
aravindsv 0:ba7650f404af 148 * @param callback The event callback function
aravindsv 0:ba7650f404af 149 * @param repeated Repeated start, true - do not send stop at end
aravindsv 0:ba7650f404af 150 * @return Zero if the transfer has started, or -1 if I2C peripheral is busy
aravindsv 0:ba7650f404af 151 */
aravindsv 0:ba7650f404af 152 int transfer(int address, const char *tx_buffer, int tx_length, char *rx_buffer, int rx_length, const event_callback_t& callback, int event = I2C_EVENT_TRANSFER_COMPLETE, bool repeated = false);
aravindsv 0:ba7650f404af 153
aravindsv 0:ba7650f404af 154 /** Abort the on-going I2C transfer
aravindsv 0:ba7650f404af 155 */
aravindsv 0:ba7650f404af 156 void abort_transfer();
aravindsv 0:ba7650f404af 157 protected:
aravindsv 0:ba7650f404af 158 void irq_handler_asynch(void);
aravindsv 0:ba7650f404af 159 event_callback_t _callback;
aravindsv 0:ba7650f404af 160 CThunk<I2C> _irq;
aravindsv 0:ba7650f404af 161 DMAUsage _usage;
aravindsv 0:ba7650f404af 162 #endif
aravindsv 0:ba7650f404af 163
aravindsv 0:ba7650f404af 164 protected:
aravindsv 0:ba7650f404af 165 void aquire();
aravindsv 0:ba7650f404af 166
aravindsv 0:ba7650f404af 167 i2c_t _i2c;
aravindsv 0:ba7650f404af 168 static I2C *_owner;
aravindsv 0:ba7650f404af 169 int _hz;
aravindsv 0:ba7650f404af 170 };
aravindsv 0:ba7650f404af 171
aravindsv 0:ba7650f404af 172 } // namespace mbed
aravindsv 0:ba7650f404af 173
aravindsv 0:ba7650f404af 174 #endif
aravindsv 0:ba7650f404af 175
aravindsv 0:ba7650f404af 176 #endif