Martin Gurtner / HKC_MiniCheetah

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mbed-dev/drivers/I2C.h@60:8399756e1ba1, 2021-01-22 (annotated)

Committer:
MartinGurtner
Date:
Fri Jan 22 13:10:37 2021 +0000
Revision:
60:8399756e1ba1
.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MartinGurtner 60:8399756e1ba1 1 /* mbed Microcontroller Library
MartinGurtner 60:8399756e1ba1 2 * Copyright (c) 2006-2015 ARM Limited
MartinGurtner 60:8399756e1ba1 3 *
MartinGurtner 60:8399756e1ba1 4 * Licensed under the Apache License, Version 2.0 (the "License");
MartinGurtner 60:8399756e1ba1 5 * you may not use this file except in compliance with the License.
MartinGurtner 60:8399756e1ba1 6 * You may obtain a copy of the License at
MartinGurtner 60:8399756e1ba1 7 *
MartinGurtner 60:8399756e1ba1 8 * http://www.apache.org/licenses/LICENSE-2.0
MartinGurtner 60:8399756e1ba1 9 *
MartinGurtner 60:8399756e1ba1 10 * Unless required by applicable law or agreed to in writing, software
MartinGurtner 60:8399756e1ba1 11 * distributed under the License is distributed on an "AS IS" BASIS,
MartinGurtner 60:8399756e1ba1 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
MartinGurtner 60:8399756e1ba1 13 * See the License for the specific language governing permissions and
MartinGurtner 60:8399756e1ba1 14 * limitations under the License.
MartinGurtner 60:8399756e1ba1 15 */
MartinGurtner 60:8399756e1ba1 16 #ifndef MBED_I2C_H
MartinGurtner 60:8399756e1ba1 17 #define MBED_I2C_H
MartinGurtner 60:8399756e1ba1 18
MartinGurtner 60:8399756e1ba1 19 #include "platform/platform.h"
MartinGurtner 60:8399756e1ba1 20
MartinGurtner 60:8399756e1ba1 21 #if defined (DEVICE_I2C) || defined(DOXYGEN_ONLY)
MartinGurtner 60:8399756e1ba1 22
MartinGurtner 60:8399756e1ba1 23 #include "hal/i2c_api.h"
MartinGurtner 60:8399756e1ba1 24 #include "platform/SingletonPtr.h"
MartinGurtner 60:8399756e1ba1 25 #include "platform/PlatformMutex.h"
MartinGurtner 60:8399756e1ba1 26 #include "platform/NonCopyable.h"
MartinGurtner 60:8399756e1ba1 27
MartinGurtner 60:8399756e1ba1 28 #if DEVICE_I2C_ASYNCH
MartinGurtner 60:8399756e1ba1 29 #include "platform/CThunk.h"
MartinGurtner 60:8399756e1ba1 30 #include "hal/dma_api.h"
MartinGurtner 60:8399756e1ba1 31 #include "platform/FunctionPointer.h"
MartinGurtner 60:8399756e1ba1 32 #endif
MartinGurtner 60:8399756e1ba1 33
MartinGurtner 60:8399756e1ba1 34 namespace mbed {
MartinGurtner 60:8399756e1ba1 35 /** \addtogroup drivers */
MartinGurtner 60:8399756e1ba1 36
MartinGurtner 60:8399756e1ba1 37 /** An I2C Master, used for communicating with I2C slave devices
MartinGurtner 60:8399756e1ba1 38 *
MartinGurtner 60:8399756e1ba1 39 * @note Synchronization level: Thread safe
MartinGurtner 60:8399756e1ba1 40 *
MartinGurtner 60:8399756e1ba1 41 * Example:
MartinGurtner 60:8399756e1ba1 42 * @code
MartinGurtner 60:8399756e1ba1 43 * // Read from I2C slave at address 0x62
MartinGurtner 60:8399756e1ba1 44 *
MartinGurtner 60:8399756e1ba1 45 * #include "mbed.h"
MartinGurtner 60:8399756e1ba1 46 *
MartinGurtner 60:8399756e1ba1 47 * I2C i2c(p28, p27);
MartinGurtner 60:8399756e1ba1 48 *
MartinGurtner 60:8399756e1ba1 49 * int main() {
MartinGurtner 60:8399756e1ba1 50 * int address = 0x62;
MartinGurtner 60:8399756e1ba1 51 * char data[2];
MartinGurtner 60:8399756e1ba1 52 * i2c.read(address, data, 2);
MartinGurtner 60:8399756e1ba1 53 * }
MartinGurtner 60:8399756e1ba1 54 * @endcode
MartinGurtner 60:8399756e1ba1 55 * @ingroup drivers
MartinGurtner 60:8399756e1ba1 56 */
MartinGurtner 60:8399756e1ba1 57 class I2C : private NonCopyable<I2C> {
MartinGurtner 60:8399756e1ba1 58
MartinGurtner 60:8399756e1ba1 59 public:
MartinGurtner 60:8399756e1ba1 60 enum RxStatus {
MartinGurtner 60:8399756e1ba1 61 NoData,
MartinGurtner 60:8399756e1ba1 62 MasterGeneralCall,
MartinGurtner 60:8399756e1ba1 63 MasterWrite,
MartinGurtner 60:8399756e1ba1 64 MasterRead
MartinGurtner 60:8399756e1ba1 65 };
MartinGurtner 60:8399756e1ba1 66
MartinGurtner 60:8399756e1ba1 67 enum Acknowledge {
MartinGurtner 60:8399756e1ba1 68 NoACK = 0,
MartinGurtner 60:8399756e1ba1 69 ACK = 1
MartinGurtner 60:8399756e1ba1 70 };
MartinGurtner 60:8399756e1ba1 71
MartinGurtner 60:8399756e1ba1 72 /** Create an I2C Master interface, connected to the specified pins
MartinGurtner 60:8399756e1ba1 73 *
MartinGurtner 60:8399756e1ba1 74 * @param sda I2C data line pin
MartinGurtner 60:8399756e1ba1 75 * @param scl I2C clock line pin
MartinGurtner 60:8399756e1ba1 76 */
MartinGurtner 60:8399756e1ba1 77 I2C(PinName sda, PinName scl);
MartinGurtner 60:8399756e1ba1 78
MartinGurtner 60:8399756e1ba1 79 /** Set the frequency of the I2C interface
MartinGurtner 60:8399756e1ba1 80 *
MartinGurtner 60:8399756e1ba1 81 * @param hz The bus frequency in hertz
MartinGurtner 60:8399756e1ba1 82 */
MartinGurtner 60:8399756e1ba1 83 void frequency(int hz);
MartinGurtner 60:8399756e1ba1 84
MartinGurtner 60:8399756e1ba1 85 /** Read from an I2C slave
MartinGurtner 60:8399756e1ba1 86 *
MartinGurtner 60:8399756e1ba1 87 * Performs a complete read transaction. The bottom bit of
MartinGurtner 60:8399756e1ba1 88 * the address is forced to 1 to indicate a read.
MartinGurtner 60:8399756e1ba1 89 *
MartinGurtner 60:8399756e1ba1 90 * @param address 8-bit I2C slave address [ addr | 1 ]
MartinGurtner 60:8399756e1ba1 91 * @param data Pointer to the byte-array to read data in to
MartinGurtner 60:8399756e1ba1 92 * @param length Number of bytes to read
MartinGurtner 60:8399756e1ba1 93 * @param repeated Repeated start, true - don't send stop at end
MartinGurtner 60:8399756e1ba1 94 *
MartinGurtner 60:8399756e1ba1 95 * @returns
MartinGurtner 60:8399756e1ba1 96 * 0 on success (ack),
MartinGurtner 60:8399756e1ba1 97 * non-0 on failure (nack)
MartinGurtner 60:8399756e1ba1 98 */
MartinGurtner 60:8399756e1ba1 99 int read(int address, char *data, int length, bool repeated = false);
MartinGurtner 60:8399756e1ba1 100
MartinGurtner 60:8399756e1ba1 101 /** Read a single byte from the I2C bus
MartinGurtner 60:8399756e1ba1 102 *
MartinGurtner 60:8399756e1ba1 103 * @param ack indicates if the byte is to be acknowledged (1 = acknowledge)
MartinGurtner 60:8399756e1ba1 104 *
MartinGurtner 60:8399756e1ba1 105 * @returns
MartinGurtner 60:8399756e1ba1 106 * the byte read
MartinGurtner 60:8399756e1ba1 107 */
MartinGurtner 60:8399756e1ba1 108 int read(int ack);
MartinGurtner 60:8399756e1ba1 109
MartinGurtner 60:8399756e1ba1 110 /** Write to an I2C slave
MartinGurtner 60:8399756e1ba1 111 *
MartinGurtner 60:8399756e1ba1 112 * Performs a complete write transaction. The bottom bit of
MartinGurtner 60:8399756e1ba1 113 * the address is forced to 0 to indicate a write.
MartinGurtner 60:8399756e1ba1 114 *
MartinGurtner 60:8399756e1ba1 115 * @param address 8-bit I2C slave address [ addr | 0 ]
MartinGurtner 60:8399756e1ba1 116 * @param data Pointer to the byte-array data to send
MartinGurtner 60:8399756e1ba1 117 * @param length Number of bytes to send
MartinGurtner 60:8399756e1ba1 118 * @param repeated Repeated start, true - do not send stop at end
MartinGurtner 60:8399756e1ba1 119 *
MartinGurtner 60:8399756e1ba1 120 * @returns
MartinGurtner 60:8399756e1ba1 121 * 0 on success (ack),
MartinGurtner 60:8399756e1ba1 122 * non-0 on failure (nack)
MartinGurtner 60:8399756e1ba1 123 */
MartinGurtner 60:8399756e1ba1 124 int write(int address, const char *data, int length, bool repeated = false);
MartinGurtner 60:8399756e1ba1 125
MartinGurtner 60:8399756e1ba1 126 /** Write single byte out on the I2C bus
MartinGurtner 60:8399756e1ba1 127 *
MartinGurtner 60:8399756e1ba1 128 * @param data data to write out on bus
MartinGurtner 60:8399756e1ba1 129 *
MartinGurtner 60:8399756e1ba1 130 * @returns
MartinGurtner 60:8399756e1ba1 131 * '0' - NAK was received
MartinGurtner 60:8399756e1ba1 132 * '1' - ACK was received,
MartinGurtner 60:8399756e1ba1 133 * '2' - timeout
MartinGurtner 60:8399756e1ba1 134 */
MartinGurtner 60:8399756e1ba1 135 int write(int data);
MartinGurtner 60:8399756e1ba1 136
MartinGurtner 60:8399756e1ba1 137 /** Creates a start condition on the I2C bus
MartinGurtner 60:8399756e1ba1 138 */
MartinGurtner 60:8399756e1ba1 139
MartinGurtner 60:8399756e1ba1 140 void start(void);
MartinGurtner 60:8399756e1ba1 141
MartinGurtner 60:8399756e1ba1 142 /** Creates a stop condition on the I2C bus
MartinGurtner 60:8399756e1ba1 143 */
MartinGurtner 60:8399756e1ba1 144 void stop(void);
MartinGurtner 60:8399756e1ba1 145
MartinGurtner 60:8399756e1ba1 146 /** Acquire exclusive access to this I2C bus
MartinGurtner 60:8399756e1ba1 147 */
MartinGurtner 60:8399756e1ba1 148 virtual void lock(void);
MartinGurtner 60:8399756e1ba1 149
MartinGurtner 60:8399756e1ba1 150 /** Release exclusive access to this I2C bus
MartinGurtner 60:8399756e1ba1 151 */
MartinGurtner 60:8399756e1ba1 152 virtual void unlock(void);
MartinGurtner 60:8399756e1ba1 153
MartinGurtner 60:8399756e1ba1 154 virtual ~I2C() {
MartinGurtner 60:8399756e1ba1 155 // Do nothing
MartinGurtner 60:8399756e1ba1 156 }
MartinGurtner 60:8399756e1ba1 157
MartinGurtner 60:8399756e1ba1 158 #if DEVICE_I2C_ASYNCH
MartinGurtner 60:8399756e1ba1 159
MartinGurtner 60:8399756e1ba1 160 /** Start non-blocking I2C transfer.
MartinGurtner 60:8399756e1ba1 161 *
MartinGurtner 60:8399756e1ba1 162 * This function locks the deep sleep until any event has occured
MartinGurtner 60:8399756e1ba1 163 *
MartinGurtner 60:8399756e1ba1 164 * @param address 8/10 bit I2c slave address
MartinGurtner 60:8399756e1ba1 165 * @param tx_buffer The TX buffer with data to be transfered
MartinGurtner 60:8399756e1ba1 166 * @param tx_length The length of TX buffer in bytes
MartinGurtner 60:8399756e1ba1 167 * @param rx_buffer The RX buffer which is used for received data
MartinGurtner 60:8399756e1ba1 168 * @param rx_length The length of RX buffer in bytes
MartinGurtner 60:8399756e1ba1 169 * @param event The logical OR of events to modify
MartinGurtner 60:8399756e1ba1 170 * @param callback The event callback function
MartinGurtner 60:8399756e1ba1 171 * @param repeated Repeated start, true - do not send stop at end
MartinGurtner 60:8399756e1ba1 172 * @return Zero if the transfer has started, or -1 if I2C peripheral is busy
MartinGurtner 60:8399756e1ba1 173 */
MartinGurtner 60:8399756e1ba1 174 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);
MartinGurtner 60:8399756e1ba1 175
MartinGurtner 60:8399756e1ba1 176 /** Abort the on-going I2C transfer
MartinGurtner 60:8399756e1ba1 177 */
MartinGurtner 60:8399756e1ba1 178 void abort_transfer();
MartinGurtner 60:8399756e1ba1 179 protected:
MartinGurtner 60:8399756e1ba1 180 void irq_handler_asynch(void);
MartinGurtner 60:8399756e1ba1 181 event_callback_t _callback;
MartinGurtner 60:8399756e1ba1 182 CThunk<I2C> _irq;
MartinGurtner 60:8399756e1ba1 183 DMAUsage _usage;
MartinGurtner 60:8399756e1ba1 184 #endif
MartinGurtner 60:8399756e1ba1 185
MartinGurtner 60:8399756e1ba1 186 protected:
MartinGurtner 60:8399756e1ba1 187 void aquire();
MartinGurtner 60:8399756e1ba1 188
MartinGurtner 60:8399756e1ba1 189 i2c_t _i2c;
MartinGurtner 60:8399756e1ba1 190 static I2C *_owner;
MartinGurtner 60:8399756e1ba1 191 int _hz;
MartinGurtner 60:8399756e1ba1 192 static SingletonPtr<PlatformMutex> _mutex;
MartinGurtner 60:8399756e1ba1 193 };
MartinGurtner 60:8399756e1ba1 194
MartinGurtner 60:8399756e1ba1 195 } // namespace mbed
MartinGurtner 60:8399756e1ba1 196
MartinGurtner 60:8399756e1ba1 197 #endif
MartinGurtner 60:8399756e1ba1 198
MartinGurtner 60:8399756e1ba1 199 #endif