Renato Grottesi / mbed-dev-bin

Microbit as a BLE gamepad

Dependents:   microbit-dal

Fork of mbed-dev-bin by Lancaster University

I2C.h@4:bb4b3734941b, 2017-01-30 (annotated)

Committer:
rengro01
Date:
Mon Jan 30 08:23:23 2017 +0000
Revision:
4:bb4b3734941b
Parent:
0:e1a608bb55e8 
Microbit as a BLE gamepad

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jamesadevine 0:e1a608bb55e8 1 /* mbed Microcontroller Library
jamesadevine 0:e1a608bb55e8 2 * Copyright (c) 2006-2015 ARM Limited
jamesadevine 0:e1a608bb55e8 3 *
jamesadevine 0:e1a608bb55e8 4 * Licensed under the Apache License, Version 2.0 (the "License");
jamesadevine 0:e1a608bb55e8 5 * you may not use this file except in compliance with the License.
jamesadevine 0:e1a608bb55e8 6 * You may obtain a copy of the License at
jamesadevine 0:e1a608bb55e8 7 *
jamesadevine 0:e1a608bb55e8 8 * http://www.apache.org/licenses/LICENSE-2.0
jamesadevine 0:e1a608bb55e8 9 *
jamesadevine 0:e1a608bb55e8 10 * Unless required by applicable law or agreed to in writing, software
jamesadevine 0:e1a608bb55e8 11 * distributed under the License is distributed on an "AS IS" BASIS,
jamesadevine 0:e1a608bb55e8 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
jamesadevine 0:e1a608bb55e8 13 * See the License for the specific language governing permissions and
jamesadevine 0:e1a608bb55e8 14 * limitations under the License.
jamesadevine 0:e1a608bb55e8 15 */
jamesadevine 0:e1a608bb55e8 16 #ifndef MBED_I2C_H
jamesadevine 0:e1a608bb55e8 17 #define MBED_I2C_H
jamesadevine 0:e1a608bb55e8 18
jamesadevine 0:e1a608bb55e8 19 #include "platform.h"
jamesadevine 0:e1a608bb55e8 20
jamesadevine 0:e1a608bb55e8 21 #if DEVICE_I2C
jamesadevine 0:e1a608bb55e8 22
jamesadevine 0:e1a608bb55e8 23 #include "i2c_api.h"
jamesadevine 0:e1a608bb55e8 24
jamesadevine 0:e1a608bb55e8 25 #if DEVICE_I2C_ASYNCH
jamesadevine 0:e1a608bb55e8 26 #include "CThunk.h"
jamesadevine 0:e1a608bb55e8 27 #include "dma_api.h"
jamesadevine 0:e1a608bb55e8 28 #include "FunctionPointer.h"
jamesadevine 0:e1a608bb55e8 29 #endif
jamesadevine 0:e1a608bb55e8 30
jamesadevine 0:e1a608bb55e8 31 namespace mbed {
jamesadevine 0:e1a608bb55e8 32
jamesadevine 0:e1a608bb55e8 33 /** An I2C Master, used for communicating with I2C slave devices
jamesadevine 0:e1a608bb55e8 34 *
jamesadevine 0:e1a608bb55e8 35 * Example:
jamesadevine 0:e1a608bb55e8 36 * @code
jamesadevine 0:e1a608bb55e8 37 * // Read from I2C slave at address 0x62
jamesadevine 0:e1a608bb55e8 38 *
jamesadevine 0:e1a608bb55e8 39 * #include "mbed.h"
jamesadevine 0:e1a608bb55e8 40 *
jamesadevine 0:e1a608bb55e8 41 * I2C i2c(p28, p27);
jamesadevine 0:e1a608bb55e8 42 *
jamesadevine 0:e1a608bb55e8 43 * int main() {
jamesadevine 0:e1a608bb55e8 44 * int address = 0x62;
jamesadevine 0:e1a608bb55e8 45 * char data[2];
jamesadevine 0:e1a608bb55e8 46 * i2c.read(address, data, 2);
jamesadevine 0:e1a608bb55e8 47 * }
jamesadevine 0:e1a608bb55e8 48 * @endcode
jamesadevine 0:e1a608bb55e8 49 */
jamesadevine 0:e1a608bb55e8 50 class I2C {
jamesadevine 0:e1a608bb55e8 51
jamesadevine 0:e1a608bb55e8 52 public:
jamesadevine 0:e1a608bb55e8 53 enum RxStatus {
jamesadevine 0:e1a608bb55e8 54 NoData,
jamesadevine 0:e1a608bb55e8 55 MasterGeneralCall,
jamesadevine 0:e1a608bb55e8 56 MasterWrite,
jamesadevine 0:e1a608bb55e8 57 MasterRead
jamesadevine 0:e1a608bb55e8 58 };
jamesadevine 0:e1a608bb55e8 59
jamesadevine 0:e1a608bb55e8 60 enum Acknowledge {
jamesadevine 0:e1a608bb55e8 61 NoACK = 0,
jamesadevine 0:e1a608bb55e8 62 ACK = 1
jamesadevine 0:e1a608bb55e8 63 };
jamesadevine 0:e1a608bb55e8 64
jamesadevine 0:e1a608bb55e8 65 /** Create an I2C Master interface, connected to the specified pins
jamesadevine 0:e1a608bb55e8 66 *
jamesadevine 0:e1a608bb55e8 67 * @param sda I2C data line pin
jamesadevine 0:e1a608bb55e8 68 * @param scl I2C clock line pin
jamesadevine 0:e1a608bb55e8 69 */
jamesadevine 0:e1a608bb55e8 70 I2C(PinName sda, PinName scl);
jamesadevine 0:e1a608bb55e8 71
jamesadevine 0:e1a608bb55e8 72 /** Set the frequency of the I2C interface
jamesadevine 0:e1a608bb55e8 73 *
jamesadevine 0:e1a608bb55e8 74 * @param hz The bus frequency in hertz
jamesadevine 0:e1a608bb55e8 75 */
jamesadevine 0:e1a608bb55e8 76 void frequency(int hz);
jamesadevine 0:e1a608bb55e8 77
jamesadevine 0:e1a608bb55e8 78 /** Read from an I2C slave
jamesadevine 0:e1a608bb55e8 79 *
jamesadevine 0:e1a608bb55e8 80 * Performs a complete read transaction. The bottom bit of
jamesadevine 0:e1a608bb55e8 81 * the address is forced to 1 to indicate a read.
jamesadevine 0:e1a608bb55e8 82 *
jamesadevine 0:e1a608bb55e8 83 * @param address 8-bit I2C slave address [ addr | 1 ]
jamesadevine 0:e1a608bb55e8 84 * @param data Pointer to the byte-array to read data in to
jamesadevine 0:e1a608bb55e8 85 * @param length Number of bytes to read
jamesadevine 0:e1a608bb55e8 86 * @param repeated Repeated start, true - don't send stop at end
jamesadevine 0:e1a608bb55e8 87 *
jamesadevine 0:e1a608bb55e8 88 * @returns
jamesadevine 0:e1a608bb55e8 89 * 0 on success (ack),
jamesadevine 0:e1a608bb55e8 90 * non-0 on failure (nack)
jamesadevine 0:e1a608bb55e8 91 */
jamesadevine 0:e1a608bb55e8 92 int read(int address, char *data, int length, bool repeated = false);
jamesadevine 0:e1a608bb55e8 93
jamesadevine 0:e1a608bb55e8 94 /** Read a single byte from the I2C bus
jamesadevine 0:e1a608bb55e8 95 *
jamesadevine 0:e1a608bb55e8 96 * @param ack indicates if the byte is to be acknowledged (1 = acknowledge)
jamesadevine 0:e1a608bb55e8 97 *
jamesadevine 0:e1a608bb55e8 98 * @returns
jamesadevine 0:e1a608bb55e8 99 * the byte read
jamesadevine 0:e1a608bb55e8 100 */
jamesadevine 0:e1a608bb55e8 101 int read(int ack);
jamesadevine 0:e1a608bb55e8 102
jamesadevine 0:e1a608bb55e8 103 /** Write to an I2C slave
jamesadevine 0:e1a608bb55e8 104 *
jamesadevine 0:e1a608bb55e8 105 * Performs a complete write transaction. The bottom bit of
jamesadevine 0:e1a608bb55e8 106 * the address is forced to 0 to indicate a write.
jamesadevine 0:e1a608bb55e8 107 *
jamesadevine 0:e1a608bb55e8 108 * @param address 8-bit I2C slave address [ addr | 0 ]
jamesadevine 0:e1a608bb55e8 109 * @param data Pointer to the byte-array data to send
jamesadevine 0:e1a608bb55e8 110 * @param length Number of bytes to send
jamesadevine 0:e1a608bb55e8 111 * @param repeated Repeated start, true - do not send stop at end
jamesadevine 0:e1a608bb55e8 112 *
jamesadevine 0:e1a608bb55e8 113 * @returns
jamesadevine 0:e1a608bb55e8 114 * 0 on success (ack),
jamesadevine 0:e1a608bb55e8 115 * non-0 on failure (nack)
jamesadevine 0:e1a608bb55e8 116 */
jamesadevine 0:e1a608bb55e8 117 int write(int address, const char *data, int length, bool repeated = false);
jamesadevine 0:e1a608bb55e8 118
jamesadevine 0:e1a608bb55e8 119 /** Write single byte out on the I2C bus
jamesadevine 0:e1a608bb55e8 120 *
jamesadevine 0:e1a608bb55e8 121 * @param data data to write out on bus
jamesadevine 0:e1a608bb55e8 122 *
jamesadevine 0:e1a608bb55e8 123 * @returns
jamesadevine 0:e1a608bb55e8 124 * '1' if an ACK was received,
jamesadevine 0:e1a608bb55e8 125 * '0' otherwise
jamesadevine 0:e1a608bb55e8 126 */
jamesadevine 0:e1a608bb55e8 127 int write(int data);
jamesadevine 0:e1a608bb55e8 128
jamesadevine 0:e1a608bb55e8 129 /** Creates a start condition on the I2C bus
jamesadevine 0:e1a608bb55e8 130 */
jamesadevine 0:e1a608bb55e8 131
jamesadevine 0:e1a608bb55e8 132 void start(void);
jamesadevine 0:e1a608bb55e8 133
jamesadevine 0:e1a608bb55e8 134 /** Creates a stop condition on the I2C bus
jamesadevine 0:e1a608bb55e8 135 */
jamesadevine 0:e1a608bb55e8 136 void stop(void);
jamesadevine 0:e1a608bb55e8 137
jamesadevine 0:e1a608bb55e8 138 #if DEVICE_I2C_ASYNCH
jamesadevine 0:e1a608bb55e8 139
jamesadevine 0:e1a608bb55e8 140 /** Start non-blocking I2C transfer.
jamesadevine 0:e1a608bb55e8 141 *
jamesadevine 0:e1a608bb55e8 142 * @param address 8/10 bit I2c slave address
jamesadevine 0:e1a608bb55e8 143 * @param tx_buffer The TX buffer with data to be transfered
jamesadevine 0:e1a608bb55e8 144 * @param tx_length The length of TX buffer in bytes
jamesadevine 0:e1a608bb55e8 145 * @param rx_buffer The RX buffer which is used for received data
jamesadevine 0:e1a608bb55e8 146 * @param rx_length The length of RX buffer in bytes
jamesadevine 0:e1a608bb55e8 147 * @param event The logical OR of events to modify
jamesadevine 0:e1a608bb55e8 148 * @param callback The event callback function
jamesadevine 0:e1a608bb55e8 149 * @param repeated Repeated start, true - do not send stop at end
jamesadevine 0:e1a608bb55e8 150 * @return Zero if the transfer has started, or -1 if I2C peripheral is busy
jamesadevine 0:e1a608bb55e8 151 */
jamesadevine 0:e1a608bb55e8 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);
jamesadevine 0:e1a608bb55e8 153
jamesadevine 0:e1a608bb55e8 154 /** Abort the on-going I2C transfer
jamesadevine 0:e1a608bb55e8 155 */
jamesadevine 0:e1a608bb55e8 156 void abort_transfer();
jamesadevine 0:e1a608bb55e8 157 protected:
jamesadevine 0:e1a608bb55e8 158 void irq_handler_asynch(void);
jamesadevine 0:e1a608bb55e8 159 event_callback_t _callback;
jamesadevine 0:e1a608bb55e8 160 CThunk<I2C> _irq;
jamesadevine 0:e1a608bb55e8 161 DMAUsage _usage;
jamesadevine 0:e1a608bb55e8 162 #endif
jamesadevine 0:e1a608bb55e8 163
jamesadevine 0:e1a608bb55e8 164 protected:
jamesadevine 0:e1a608bb55e8 165 void aquire();
jamesadevine 0:e1a608bb55e8 166
jamesadevine 0:e1a608bb55e8 167 i2c_t _i2c;
jamesadevine 0:e1a608bb55e8 168 static I2C *_owner;
jamesadevine 0:e1a608bb55e8 169 int _hz;
jamesadevine 0:e1a608bb55e8 170 };
jamesadevine 0:e1a608bb55e8 171
jamesadevine 0:e1a608bb55e8 172 } // namespace mbed
jamesadevine 0:e1a608bb55e8 173
jamesadevine 0:e1a608bb55e8 174 #endif
jamesadevine 0:e1a608bb55e8 175
jamesadevine 0:e1a608bb55e8 176 #endif